Magnesium is one of the most commonly used supplements in horses, which when used appropriately, can be significantly beneficial. Yet often little consideration is given to important specifics around the use of this mineral. These generally overlooked nuances can help to determine how effective the magnesium is and if it is actually helpful or harmful to give your horse.

Magnesium plays many vital roles in the body. It is needed for over 300 enzymatic processes. From helping ‘wired’, reactive or anxious horses to reducing inflammation, supporting fertility, promoting bone health, metabolic function, and insulin regulation, magnesium has a wide range of applications.

Because magnesium is a naturally occurring nutrient, it is frequently assumed to be completely safe and free from side effects. Yet in reality, it isn’t quite this simple. Like many other supplements and nutrients, there are many factors which determine the safety and effectiveness of magnesium: how and what it is used for, the quantity of magnesium a horse is given, the duration of supplementation, the form of magnesium used, a horse’s overall diet and intake of other specific nutrients, exercise and activity levels, breed, sweat rate, any health conditions a horse may have, the state of its gastrointestinal health and any medications a horse is on. 

If you’re already supplementing or considering using magnesium for your horse, here are some key things worth considering.

Not all magnesiums are created equal

Magnesium comes in a variety of forms, depending on what it’s bound to. This refers to the chemical structure of the magnesium, not just whether it is in liquid or powdered form. The most commonly used forms of magnesium (which also tend to be the cheapest forms of magnesium) in equine supplements include:

• Magnesium oxide
• Magnesium chloride
• Magnesium sulphate

Each of these forms differs in terms of absorption, bioavailability, and how they interact with the digestive system. Yet they are generally not the most clinically effective forms of magnesium to use.

This matters more than many people realise.

Magnesium can irritate the gut

Some forms of magnesium, particularly at higher doses can irritate the digestive tract.

Clinically, this may present in our horses as:

• loose and/or more frequent manure
• gassiness/excessive passing of wind
• changes in gut comfort and/or signs of mild colic
• worsening of existing digestive sensitivity

This is often dismissed or overlooked, especially if magnesium is being used for behavioural reasons.

Over-supplementation can disrupt the gut microbiome

High doses, poorly absorbed forms of magnesium or long-term over-supplementation may contribute to gut dysbiosis (an imbalance in gut bacteria). This can have wider consequences, including:

Magnesium can help to promote a healthy gut microbiome and reduce gastrointestinal-associated inflammation, but more is not always better.

• negative impacts on immune function
• altered nervous system function
• changes in neurotransmitter production and function

Our horses’ digestive systems can play a significant role in their behaviour, anxiety levels and learning capacity, thanks to the role of the gut-brain axis. Ironically, this means that excessive magnesium use may actually make some horses more reactive or sensitive, not less.

Magnesium can interfere with other essential nutrients, causing relative nutrient deficiencies

Magnesium doesn’t work in isolation. It interacts closely with other minerals including:

• calcium
• phosphorus
• zinc

Excess magnesium can interfere with the absorption and utilisation of these nutrients, which are critical for:

• bone strength and development
• proper neuromuscular function
• healthy immune function
• healthy nervous system function
• reducing oxidation and inflammation 
• muscle, tendon and ligament health

Calcium and zinc in particular, play key roles in the synthesis and function of neurotransmitters such as:

• Dopamine
• Serotonin
• GABA

Imbalances in these neurotransmitters can directly influence behaviour, sensitivity, pain perception, reactivity, learning ability and response to training.

Magnesium and behaviour: not always a simple fix

Magnesium is often used to help calm or relax our horses, and in some cases, when used appropriately it can be most beneficial. When magnesium doesn’t help to address the underlying cause(s) of anxious or excitable behaviour however, the effects of supplementation will be minimal.

The effectiveness of magnesium supplementation will also be minimal and may compound behavioural issues if the delicate balances of other minerals are disrupted, magnesium is overused, poorly bioavailable forms of magnesium are employed, or the gut microbiome is negatively impacted. In these cases behavioural issues may actually worsen rather than improve.

It is important to remember that many things can contribute to adverse behaviour in our horses, and in the vast majority of cases, there are multiple causes at any one time, not just one single factor. Whilst diet, nutrient deficiencies and gut microbiome all play an important part, it would be remiss to overlooked issues such as pain, learned conditioning, side effects of other medications used (if applicable) and other underlying health issues. Supplemental magnesium will be of very limited benefit if the issues causing a horse’s poor behaviour are not properly addressed.

This is why a blanket approach to supplement with magnesium doesn’t always deliver consistent results.

Where magnesium can be highly beneficial

When used appropriately, magnesium can be valuable, particularly in horses with:

Metabolic Challenges

Magnesium plays a role in regulating blood glucose and insulin levels. It can be especially supportive in horses with:

• insulin resistance (IR) or insulin dysregulation (ID)
• equine metabolic syndrome (EMS)
• laminitis or at risk of laminitis

Increased Physical Demand

Horses lose magnesium through sweat, and in the case of broodmares, through their milk. Requirements may increase in:

• horses in intense workloads
• hot and/or humid climates
• lactating mares
• during travel

In these cases, intake may increase in the range of 1.5 to 2 times maintenance levels.

Diet still matters: natural sources of magnesium

Like many minerals, magnesium naturally occurs in feeds commonly given to our horses. Lucerne (alfalfa) hay is a useful natural source of magnesium. Fortified concentrate and balancer feeds have varying levels of magnesium.

However, it is not always quite as simple as relying on feed alone (or even, relying on nutritional information on a feed bag or product label).

Feeds or supplements which contain high levels of calcium (such as lucerne/alfalfa) can inhibit magnesium absorption to some degree. This highlights the importance of looking at the whole diet, not just individual nutrients or feed components, nor relying on feed programs or calculators alone.

Medications can change magnesium requirements

Many commonly used medications in horses can alter magnesium absorption, metabolism, or excretion, meaning their requirements may shift.

These include:

• corticosteroids
• proton pump inhibitors (the include the most commonly used ulcer medications which contain omeprazole)
• antibiotics
• non-steroidal anti-inflammatory drugs (NSAIDs)
• antihistamines
• clenbuterol  (β2-agonists, which are often sold under names such as Claire Gel, Broncopulmin, Airway Gel, Ventipulmin, Equipulmin, etc).

If your horse is on medication, magnesium supplementation should always be considered more carefully. Dose, form, timing and duration of magnesium supplementation is crucial to take into account.

In summary: use magnesium strategically, not automatically

Magnesium is a powerful and valuable tool in equine nutrition and medicine, but it’s not without its limitations.

Used well, it can support:

• metabolic health
• muscle function
• nervous system balance and in turn, behaviour 
• skeletal health
• fertility
• gastrointestinal (‘gut’) health

Used poorly, it can:

• disrupt gut health
• create mineral imbalances and relative nutrient deficiencies
• contribute to ongoing behavioural issues
• interfere with normal bone development and health

The key is not just whether your horse is supplemented with magnesium, but what their actual requirements for it are. The form of magnesium used to supplement, the reasons to supplement it, the duration of supplementation, factors which increase requirements or interfere with magnesium absorption and metabolism should all be taken into consideration.

Take home message

Good equine nutrition is never about using a single supplement in isolation. Assessing the unique needs of the individual horse in front of you is crucial.

Before supplementing magnesium, it’s always worth asking:

• does my horse actually need it? And if so, how much?
• is the diet balanced overall? And what role would supplemental magnesium potentially play in this?
• could there be deeper underlying causes contributing to the reasons which are prompting me to supplement magnesium?

The safest, most effective and sustainable results come from a thoughtful, tailored approach.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

Equine asthma is a condition that can affect horses of all abilities, but is most frequently diagnosed in performance horses and racehorses, and is a common cause of poor performance. The term ‘equine asthma’ covers a broad range of inflammatory conditions of the lower airways, which can vary in their presentation and severity. Conditions that were previously referred to as ‘recurrent airway obstruction’, ‘heaves’, ‘inflammatory airway disease’, ‘chronic obstructive pulmonary disease’, and ‘summer pasture associated asthma’ are now all known as ‘equine asthma’.

When a horse has been diagnosed with, or is suspected of suffering from asthma, it is natural for us to want to provide them with relief. From a pharmaceutical standpoint, that can often mean the use of corticosteroids and, in many cases, clenbuterol (often sold under names such as Claire Gel, Broncopulmin, Airway Gel, Ventipulmin, Equipulmin, etc). While use of these medications may help relieve some clinical signs of asthma, they do not address the underlying causes of the condition and may also come with unintended health consequences. Unfortunately, these side effects are often overlooked, or simply not discussed.

Whilst clenbuterol may provide some initial relief in equine asthma, the use of this drug can contribute to a vicious cycle, potentially perpetuating the condition.

Clenbuterol has been demonstrated to deplete the amino acid taurine. Taurine plays a significant protective role in lung health by exerting powerful anti-inflammatory, antioxidant, and membrane-stabilising effects. It also helps to inhibit allergic responses, which can play a role in many cases of equine asthma. Reduced taurine levels may increase the severity of equine asthma and the likelihood of lung tissue damage as a result of ongoing airway changes. Taurine is also needed to promote healthy gut integrity and microflora: gut health is increasingly recognised as an important factor in respiratory conditions such as asthma.

Clenbuterol decreases levels of potassium and magnesium in the body—two key nutrients known to support respiratory health and reduce the severity of asthma. Potassium is essential for controlling airway smooth muscle tone and supporting respiratory muscle function.  Low potassium can increase airway reactivity and hamper breathing, further exacerbating clinical signs of asthma. Depleted potassium levels can also lead to cramping in susceptible horses. Magnesium acts as a bronchodilator (helping the airways relax) and helps reduce airway hyperactivity, spasms, and inflammation.

Long-term use of clenbuterol may also have negative impacts on immune function, further contributing to a self-perpetuating cycle of equine asthma.

An often overlooked side effect of clenbuterol is the influence it may have on temperament and behaviour in our horses. Clenbuterol belongs to a class of drugs known as beta-2 adrenoceptor agonists, which work by mimicking the effects of epinephrine (adrenaline) in the body. This results in a stimulating effect, which may lead to changes in behaviour, including increased excitability, reactivity or nervousness in some horses.

Helping a horse at risk of, or diagnosed with asthma, starts with good management practices. Identifying and appropriately addressing the factors that contribute to the underlying pathophysiology of equine asthma, meeting the individual horse’s nutritional requirements (which often differ from basic nutrient requirements due to medication use), and the judicious use of suitable herbal medicines can significantly support respiratory health, allowing a horse to remain healthy and perform at its best. There is much that can be done for the horse diagnosed with asthma, using approaches that not only support airway health and performance, but also promote overall wellbeing. If your horse has been diagnosed with asthma, or you suspect respiratory issues may be affecting performance or comfort, a tailored approach can make a significant difference. Get in touch with Optim Equine to discuss a personalised plan to your support your horse’s health and performance.

At Optim Equine, we regularly work with horses affected by respiratory conditions…

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

Depending on the herb (or combination of herbs used) and their application, they can help to:

• reduce inflammation
• modulate immune function
• aid healing and tissue repair
• assist recovery from infections
• prevent and/or manage equine asthma
• soothe the gut lining and promote healing of both gastric and colonic ulcers
• reduce colic 
• support digestion
• assist fertility
• help regulate hormone levels
• calm nervous horses
• provide gentle pain relief
• promote healthy hoof growth and integrity
• help to reduce the severity of osteoarthritis and maintain joint health
• Aid in blood glucose control and assist in the treatment of insulin resistance, equine metabolic syndrome and laminitis

Whilst herbal medicines are incredibly versatile, they’re not magic. And they can’t replace a poorly balanced diet….

One of the biggest misconceptions I see is that herbs can fully meet a horse’s nutritional needs or correct nutritional deficiencies on their own. 

This is simply not true. 

The vast majority of herbs (with few exceptions) do not provide sufficient quantities of key minerals and vitamins our horses need for optimal health and functioning.

Take the calcium rich herb nettle (Urtica diocia) for example….

100 g dried nettle leaf (~4–5 cups) provides approximately 300–500 mg calcium.

For a 500 kg (1100 pound) horse, calcium requirements typically fall in the range of 20–40 g/day (depending on life stage, workload, and physiological status).

This means:

• 100 g nettle provides roughly 0.3–0.5 g calcium
• This equates to approximately 1/40 to 1/133 of daily calcium requirements

To meet calcium needs via nettle alone would require:

• 4–5 cups × 40–133 = ~160–665 cups per day

This is neither practical nor appropriate.

Whilst strategically employed herbal medicines can help to restore optimal gastrointestinal health and function in our horses (including digestion, absorption and metabolism)- which in turn, can aid in better nutritional status, herbs in and of themselves don’t provide enough levels of nutrients our horses needs to meet daily nutrient requirements.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

The composition of our hose’s gut microbiota has a profound impact on their behaviour and health. This is mediated through the gut-brain-immune axis. Changes in the composition of their gut microbiota can influence neurotransmitter production and function. Neurotransmitters are the natural chemical messengers which have important roles influencing many processes in our horses. Temperament, behaviour, motor control, learning patterns and digestive function are all influenced by neurotransmitters. Gut microbial population also affects neuroinflammation (inflammation of the brain and spinal cord), which can further influence mood and behaviour. Excessive levels of neuroinflammation may worsen stress, anxiety, tension and irritation in our horses.

Many things can adversely affect our horse’s gut microbiota, which may contribute to dysfunction of the gut-brain-immune axis. Clinical signs, changes and conditions we may see in our horses when their gut-brain-immune axis has been disrupted include:

• Faecal water syndrome
• Gastric ulcers
• Colonic ulcers
• Failure to thrive
• Failure to put on/maintain weight
• Susceptibility to infections and/or recurrent, chronic infections
• Nervousness, erratic behaviour, shying, anxiety, irritability
• Equine metabolic syndrome
• Insulin resistance
• Inflammatory bowel disease
• Colic
• Scours/diarrhoea
• Laminitis
• Osteoarthritis
• Equine Asthma Syndrome
• Recurrent skin conditions
• Poor recovery post exercise, training and/or competition
• Excessive muscle tension

In some horses, however, dysbiosis (unhealthy balance of the microbial community in the gut microbiota) may result in no obvious outward signs, yet their health is likely impacted under the surface, and this may become evident further down the track. Many of the signs associated with a dysfunctional gut-brain-immune axis health are non-specific, meaning they can often be dismissed or attributed to something else. Unfortunatel,y this means that often the underlying cause(s) of the condition or clinical signs can be overlooked in our horses.

Some of the factors which compromise GI health, and in turn influence immune health and behaviour include (but are certainly not limited to): insufficient dry matter (long-stem) fibre in the diet; large sized ‘hard feeds’ (ie concentrates and grains); large percentages of starch and/or sugar in the diet; abrupt changes in diet and/or pasture; the use of certain medications (including antibiotics, non-steroidal anti-inflammatory drugs (NSAIDs), corticosteroids and ulcer medications); viral and/or bacterial infections; high parasite burdens; nutritional insufficiencies, deficiencies and/or excesses (usually certain minerals, but sometimes particular vitamins); heavy metal toxicities; stress; pain; dehydration; high levels of inflammation in the body; extended travel; intense exercise.

Given the modern demands, management, feeding and medication use in horses, most horses will have compromises to their gut microbiota. The effects of these can be long-lasting, unless specific, targeted, supportive and corrective action is taken. This is crucial not only for their GI health, but in turn their immune health and behaviour, in addition to their overall health, performance and recovery.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

Mares and fillies who exhibit overtly hormonal behaviour can be a real challenge and frustration for riders, trainers and owners. At the other end of the spectrum, broodmares who fail to maintain their pregnancy can cause significant financial loss and disappointment for owners and stud managers.

In both instances, one of the first things many do is use the drug altrenogest in their fillies or mares.

Altrenogest, commonly referred to as Regumate or Readyserve (two of its trade names) is a synthetic progesterone product used to suppress oestrus in mares (and often used with the intention to help ‘maintain’ pregnancy in ‘problem’ pregnancy mares). It is the first choice by many horse people to help ‘control their marey-mare’.

Whilst the health issues associated with the use of altrenogest in horses are extensive, it’s well worth being aware of health implications in humans.

Scarily, altrenogest is routinely viewed and handled as a relatively harmless substance. Yet this drug can cause significant hormonal and health problems to humans who come into contact with it. Altrenogest has been widely reported to the Food and Drug Administration (FDA) for its adverse effects in both men and women.  Exposure is most commonly reported following drug contact with the skin, but it is important to note that some reported exposures occur in conjunction with touching product residue on barn surfaces, equipment, and treated animals. Put simply, you don’t even directly have to handle the drug to suffer adverse health effects from it.

The most significant noted health implications of human exposure to altrenogest involve reproductive system issues, including abnormal menstrual cycles in women (changes in bleeding frequency, pattern and amount). Girls as young as 14 years old have been effected- an alarming consequence. In men, decreased libido has been reported. Headaches, fever, abdominal pain, nausea, diarrhoea, vomiting and skin rashes have also been associated with exposure to altrenogest.

The labelling for all altrenogest products include warnings against human exposure as the hormone is readily absorbed through intact skin. 

It’s easy to think that wearing latex gloves will protect us from the harmful effects of this medication. But this is a misconception: latex allows the passage of altrenogest through it, which can then penetrate the skin. Once altrenogest has been spilt on the gloves and soaked through, it is then more readily absorbed by the skin rather than passing back through the glove. Essentially this practice creates an ‘altrenogest patch’.

When it comes to the use of altrenogest in fillies and mares, it is important to remember that the causes of hormonal problems and imbalances may be due to many factors. As too is the failure to maintain pregnancy.

Feeding practices, nutritional status, inflammation, body composition, the use of certain medications, gastrointestinal health and stress levels all play very important roles, yet are commonly overlooked. 

Appropriately prescribed herbal medicines and nutritional supplements, alongside sound dietary and management practices can significantly help the ‘hormonal’ mare or filly and her behaviour. For the mare to be bred, they can also help to support conception and healthy foetal growth and development.

Understanding why a mare or filly exhibits overtly ‘hormonal’ behaviour is really important to promote overall best health and performance. In the case of pregnancy loss, identifying and addressing contributing factors specific to each individual mare can help result in the best possible outcomes.

Simply manipulating hormone levels through the addition of synthetic progesterone rarely helps to address the causes in either case: it just ‘bandaids’ them.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

Understanding pain in our horses

The experience of pain is unique to each individual horse and pony: in the way it presents, the intensity, frequency of the pain and how the horse or pony responds to treatment. In recent years, we have come a long way in better understanding the many different physical signs a horse or pony may display to indicate that they are in pain.

Pain seldom appears alone: it can impact a multitude of different aspects in a horse or pony. A horse or pony in pain can concurrently experience changes in behaviour or temperament: this may be one of the first indications which alerts us to the fact our horse or pony is experiencing pain. If the pain is new/acute in nature, these behavioural changes can appear totally out of character. If the pain is chronic/ongoing, the horse or pony may become withdrawn or ‘shut down’ in order to manage their pain. Poor performance, immune health challenges, digestive health issues and compromised fertility may all be associated with pain in our horses and ponies.

To effectively address and relieve pain in our horses and ponies, it is important to consider that pain can be multifaceted and complex. When we think of pain in our horses and ponies, we commonly think of pain which is a result of a direct physical cause. That is, pain that is associated with injury, lameness, poorly fitting tack or saddles, etc. This is what is referred to as ‘somatic pain’.

Yet pain can (and often is) so much more complex than this. Which in part, helps to explain why the use of anti-inflammatory drugs and corticosteroids doesn’t effectively resolve pain in many cases.

Different types of pain respond better to different treatments due to their varying mechanisms, mediators, impact on the brain and inflammatory pathways.

To provide the best pain relief for our horse or pony, an individual, targeted approach is essential. Read on to learn more about the different types of pain our horses and ponies can experience.  

Nociceptive Pain

Nociceptive pain is experienced due to ongoing activation of nociceptors (pain sensing neurones located within body organs and internal cavities). Nociceptive pain is caused by damage to body tissues as a result of trauma and/or inflammation. When we think of pain in our horses and ponies, nociceptive pain is generally the first type of pain that comes to mind.

Nociceptive pain serves as a protective response to injury or potential harm. In cases of chronic pain however, nociceptor activation can remain ongoing, even after healing of damaged tissues is complete and there is no further sign of damage/injury. Accurately identifying and understanding the causes and mechanisms behind this chronic pain in our horses and ponies can be incredibly difficult: an injury may be visibly healed (even on thorough imaging and diagnostic methods), yet the horse is still demonstrating signs of pain.

Nociceptive pain can be further divided into two main categories: somatic pain and visceral pain.

Somatic Pain

Somatic pain has a direct physical cause and arises from the musculoskeletal system (muscles, bones, joints, tendons, ligaments, connective tissues) and skin. Osteoarthritis, tendon injuries, ligament injuries, hoof abscesses, cuts and wounds are all examples where a horse or pony may experience somatic pain. It is what many vets, body workers, farriers and other equine health care professionals are often looking for when trying to identify the source of pain. In order to help identify the pain, lameness exams, nerve blocks, imaging (radiographs, MRIs, PET scans, CTs, nuclear scintigraphy etc) may be used.

Yet sometimes our horses and ponies still clearly demonstrate they are in pain, even when these avenues have been exhausted and there seems to be no explainable cause for their pain. So why is this? Despite the best technology, we can’t always see structural issues, so the pain can indeed be somatic in nature, but despite our best efforts, we can’t physically see what is causing the pain. Another reason, which may be overlooked, is the pain they are experiencing may not be somatic pain (or not just somatic pain alone). 

The pain our horses or ponies may be experiencing in this case is likely one (or a combination of) any of the other following types of pain.

Visceral Pain

Visceral pain is pain which originates from internal organs of the body, including the stomach, intestines, liver and kidneys. It may arise due to distension, inflammation or lack of blood supply to internal organs. Colic is a common clinical sign of visceral pain in our horses and ponies. The chronic, inflammatory nature of inflammatory bowel disease may cause visceral pain in some horses and ponies. In many cases we may not be able to visually ‘see’ the source of pain using diagnostic methods, instead relying on history and assessment of clinical signs in the horse or pony. Identifying visceral pain can be even more challenging as it may be masked by other conditions. The discomfort a horse or pony experiences from visceral pain can vary from mild to intense.

Neuropathic Pain

Neuropathic pain is what we commonly think of as ‘nerve pain’. It is caused by nerve damage or dysfunction, resulting in dysregulation of the transmission of nerve signals into the spinal cord. Many causes of neuropathic pain are often linked to excessive inflammation in both the peripheral and central nervous system. Inflammation however, is typically only one element of neuropathic pain. The pathophysiology of neuropathic pain is generally complex and multifactorial, which partly explains why the use of anti-inflammatories and/or rest may only provide minimal relief in many cases.

Central sensitisation

Central sensitisation is pain without identifiable nerve or tissue damage, which makes it challenging to diagnose. This type of pain is thought to result from persistent neuronal dysregulation. It may play an element in cases of neuropathic pain. Some types of neck and back pain without structural pathology may be examples of central sensitisation.

Inflammatory pain

Although somatic pain can definitely be a type of inflammatory pain, immune responses in our horses and ponies can also result in inflammatory pain. This may arise in cases of infection.

Referred pain

Referred pain is pain felt in a different location from the actual source. This form of pain can be challenging to diagnose. An example of referred pain may be highlighted by a horse or pony experiencing problems with its temporomandibular joint (TMJ) or teeth: in such cases, a horse or pony may have referred pain in the neck- with the neck appearing as if it is the source of pain itself.

Psychogenic Pain

Psychogenic pain is physical pain that is caused, increased or prolonged by emotional, mental or behavioural factors, without evidence of physical injury or illness. Psychogenic pain may not yet be commonly recognised as a clinical diagnosis in horses and ponies, but as we understand more about the role of stress, social isolation, anxiety, lack of freedom of movement, insufficient forage in the diet, boredom and frustration in the equine- the role of psychogenic pain should not be overlooked. From a clinical perspective, monitoring and/or observing signs such as heightened reactivity, increased heart rate and/or respiratory rate, stereotypies (wind sucking, cribbing, weaving, box/stall walking, paddock walking) may all be indicative of psychogenic pain.

So how can we help a horse or pony in pain?

In any case of a horse or pony experiencing pain, taking a thorough case history and conducting a comprehensive, holistic assessment gives us the best chance to understand the potential causes and contributing factors to their pain. It is important to note that in many cases, whilst clinical signs can be useful to help understand pain better in our horses and ponies, they are often non-specific.

Viewing, managing and treating pain from a holistic perspective gives us the best possible chance of helping our horses and ponies. We are fortunate that a wide range of judiciously employed nutraceuticals, herbal medicines, dietary and management strategies can significantly help horses and ponies who are experiencing pain. Within the scope of herbal medicine and nutraceuticals alone, we have multiple options in the choice of the herbs and nutrients which can be used to best help treat and manage different types of pain.

The treatment approach we take for specific types of pain should be different if we want the pain relief to be truly effective for our horses and ponies and to resolve the source(s) of the pain.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

Corticosteroids (such as prednisolone and dexamethasone), non-steroidal anti-inflammatory drugs (such as phenylbutazone, firocoxib, flunixin), gastric ulcer medications and antibiotics all impact gastrointestinal (GI) ‘gut’ health through several different mechanisms. These may include: irritating the sensitive tissue which lines the digestive tracts of our horses and ponies, potentially causing gastric ulceration and/or bleeding; causing GI dysbiosis (adversely impacting the delicate microflora populations within our horses’ and ponies’ GI tracts); and altering nutrient absorption and metabolism (the way our horses and ponies digest, utilise and excrete nutrients). 

Good gut health is central to the overall health and wellbeing in our horses. We know that beyond digestive health, gut health in our horses and ponies significantly influences: immune health; bone, cartilage and joint health; respiratory/airway health; metabolic health; reproductive health/fertility; hoof health; laminitis risk; and even behaviour and motor patterns in our horses.

These are just some of the reasons why it is important to use any medications judiciously- even ones that are routinely employed in many situations. In the case that these medications are required, strategic nutritional supplementation and in many cases, appropriately prescribed herbal medicines can help to address some of the nutrient depletions and side effects caused by these medications. Additionally they can help to return the digestive system to the best possible state of health.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

Poor fertility rates or sub-optimal fertility in stallions can be one of the most financially costly and frustrating challenges for breeding studs and managers.

Sometimes the cause(s) of poor fertility rates can be obvious. Yet, more often than not, the contributing factors may not be clear.

Stress is something which can be easily overlooked, yet plays a fundamental role in the reproductive health and performance of stallions. Stress has been found to reduce luteinizing hormone and testosterone pulsing, leading to reduced spermatogenesis and sperm quality.

The presence of stress in a stallion can be deceptive…When we think about stressed horses, we may commonly think of an outwardly anxious horse; a horse who is always alert and ‘on edge’; one who is reactive and sensitive to changes in their environment; who doesn’t settle easily; and who may walk or pace their paddock. Whilst these are all easily recognisable outward signs of stress, a horse can be under significant stress yet paradoxically appear calm and relaxed.

Some less commonly considered sources of stress to our stallions which may impact their fertility include:

• Nutritional deficiencies and/or insufficiencies;
• The side effects of many commonly used medications;
• Irregular feed regimes
• Insufficient grazing and/or provision of roughage in their diet
• Shuttling and extended travel
• Changes in a stallion’s environment
• Pain- some examples include musculoskeletal pain when covering or gastric ulcers
• The presence or absence of other horses in their immediate environment
• Excessively hot environmental conditions

Even the way a stallion is handled can impact his stress levels. On busy studs, it is not uncommon to be in a rush to complete coverings within a certain time frame. If handlers are stressed, anxious, rushing or feeling pressure to complete breeding sessions, this can raise cortisol levels and heart rates in our stallions, leading to a physiological state of stress.

Whilst we certainly can’t control all the factors which contribute to stress in a stallion, there are many aspects which are modifiable through the way we look after and manage our breeding stallions. Furthermore, the strategic use of appropriate nutritional supplements and herbal medicines can help to mitigate some of the negative effects of stress and help improve testosterone levels, sperm count, sperm quality, sperm morphology and progressive forward motility.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

Foals and coprophagy

Foals will generally start consuming manure from about five days old. It is common for this to occur up until approximately three months of age, before gradually declining. By 19 weeks of age, the habit generally stops in most foals.

By consuming manure, foals are populating their digestive system with a variety of microbes: bacteria, protozoa, archea and fungi. This habit is thought to be an important part of healthy gastrointestinal and immune system development: foals are born with a relatively ‘immature’ microbiome which is influenced by multiple factors in their early stages of life. It is worth keeping in mind however, that if a foal is consuming manure from a horse with poor digestive health and/or a horse with a poor balance of microflora and/or a horse with a high parasite burden then this may potentially have adverse effects in the foal.

Inferred research from other animal models suggests that a mare’s faeces contains a pheromone which encourages the foal to consume the manure.  Deoxycholic acid is believed to be present in a mare’s manure: an important byproduct of intestinal bacteria which supports digestive system immunity (helping to protect against enteritis). Deoxycholic acid may also facilitate normal neurological development through promoting myelination of nerves.

Adult horses and coprophagy

The consumption of manure in horses and ponies older than foals is considered an abnormal behaviour. When it does occur, it is thought to be primarily diet and/or gastrointestinal (GI) health related.

A diet low in dry matter fibre (often referred to as ‘roughage’) is one of the most common reasons a horse may consume manure. It is a common misconception that pasture alone provides enough fibre for our horses and ponies, but grass is very low in dry matter fibre. Without feeding appropriate amounts of hay or alternative dry matter fibre sources, the vast majority of horses and ponies will fail to meet their requirements.

Other diet related factors which may contribute to coprophagy include:

• Diets high in starch: even when there is adequate dry matter fibre in the diet;
• Underfeeding and/or food scarcity;
• Long periods of time without access to feed (for example, going more than three hours without access to hay/pasture and/or hard feed);
• Poor gastrointestinal (GI) microflora populations (diet related);
• Specific nutrient insufficiencies and/or deficiencies: potentially vitamin K, selenium and/or zinc.

Dietary factors aside, anything that significantly disrupts a healthy GI microflora balance can contribute to coprophagy. This can include the use of many common medications (such as antibiotics, non-steroidal anti-inflammatory drugs; corticosteroids, gastric ulcer medications); stress in all of its many forms (!); dehydration; travel, etc.

Other less common reasons an adult horse may consume manure can include medical conditions such as equine motor neurone disease.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

An important thing to keep in mind, however, is to gradually increase the workload of our horses and ponies. Understandably, many horses are turned out or exercised only very lightly or infrequently during the colder, wetter months and short daylight hours. 

Most of us appreciate that during this time, our horses lose both physical and aerobic fitness. Less often, we stop to consider that during this time off or reduced workload, they lose important conditioning of muscles, tendons, ligaments and bones. If we suddenly increase their workload or take them to competitions on weekends where we ride them hard, we can significantly increase their risk of injury. Bones, ligaments and tendons and to a certain degree muscles need regular loading to cope with impact forces and demands of movements. 

To help musculoskeletal structures of the body adapt to exercise and be ready for high-level performance or demanding exercise, it is incredibly important to strategically and incrementally increase exercise duration, intensity, frequency and overall load.

I don’t think that it is coincidental that clinically I tend to see a much higher percentage of lameness/soreness cases during the summer months compared to other times of the year. Indeed, lameness is one of the primary causes of missed training and competition in performance horses.

Often with better weather, more time and the excitement of competitions, horses are suddenly brought into full work after having months off or being just ridden occasionally. Add to this the fact that the ground is generally much harder in the summer months due to weather conditions (although this isn’t always true!)- which places extra stress on both bones and joints.

Another consideration worth keeping in mind: it is easy for a horse to go mentally sour if we expect them to suddenly go from very little work to a heavy workload or competing. When they aren’t properly conditioned, the actual work they do feels harder due to a lack of fitness. They are also more likely to feel stiffness and soreness after work- and expecting them to perform when they aren’t properly recovered is tough on them. A similar analogy that may be useful to think of is if we suddenly go from not exercising at all to running a marathon every day. We’d be stiff, sore, tired, cranky and reluctant to want to exercise at all. In such cases, it can be tempting to ‘bute’ our horses (ie give them non-steroidal anti-inflammatory drugs such as phenylbutazone, ‘PBZ’, Flunix, Firocoxib or similar), yet research shows that the use of non-steroidal anti-inflammatories actually hampers recovery from exercise. These drugs interfere with the body’s natural processes to repair micro damage to muscle, tendon, ligament and bone tissue.

One last thing to keep in mind relates specifically to older horses and ponies. For many of our schoolmasters and really experienced horses out there- we can ‘get away’ with pulling them out of the paddock just before a competition, and they can still be incredibly reliable and deliver outstanding results. They are well-educated and generally need very little practice to perform well. 

Yet, if any horse or pony needs a gradual return to an increased workload it is the older horse and pony. Issues such as osteoarthritis, ‘wear and tear’ with old age, metabolic and hormonal changes and increased recovery time, mean these horses generally need to be brought back into full work slower and with special consideration.

If you’re planning on a summer full of fun riding- whether that be simply for pleasure and/or competing, now is the time to plan and implement a gradual return to work for your horse. It can significantly help to reduce injury risk, as well as make riding a far more enjoyable experience for both you and your horse.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

In recent years, much attention has been given to grain-free feeds. Low-GI, low starch, ‘calming’ and low sugar feeds also get plenty of airtime. All the terms can relate to different aspects of the feed, but in the majority of cases, it is clever marketing and doesn’t ensure that the feed we are purchasing is necessarily suitable or safe for our horses and ponies.

Clever marketing and loopholes in claims that can be made on feed packages can become very confusing. Feeds can claim to be ‘grain free’, a ‘calm performing feed’ or low GI, yet in some cases the predominant ingredients in the feed may be made from grain! If we take a look at an ingredients list (remembering that ingredients are ordered in descending order of the percentage they make up of the feed) grain may be present in the form of millmix, millrun, pollard, cereal by-products, wheat middlings to name a few! Other products may be truly grain-free but contain large amounts of molasses and other high-calorie oils and ingredients to bind the feed together and/or make it more palatable. In either case, for many horses with metabolic issues, these feeds are likely to not be suitable. Generally ‘grain-free’ refers to the fact that no whole grains are present, yet many of these feeds contain processed grain ingredients- which certainly doesn’t make them grain-free! Along the same lines, there are feeds widely available in Australia that are advertised as suitable for horses with ‘grain intolerance’ which have barley or millrun as the predominant ingredient in the feed!

There are many reasons why it may be preferable to feed a horse or pony a truly grain-free diet, particularly a diet low in starch and sugars. For many equines, they don’t need the calories/energy provided by such grains and concentrated feeds, and in the case of horses with equine metabolic syndrome, insulin resistance and many cases of laminitis and Pituitary Pars Intermedia Dysfunction (PPID) (formerly known as ‘Cushings’), steering clear of grain is generally a good idea.  For other horses with higher calorie needs, the incomplete digestion of grain products and the resulting fermentation of starch and sugars in the hindgut can increase the risk and/or severity of gastric and colonic ulcers, inflammatory bowel disease, ’tying up’, developmental orthopaedic diseases (such as OCDs and bone cysts), immune dysfunction, inflammatory conditions and behavioural issues.

If a horse needs to be on a grain-free diet, and more specifically a low starch and sugar diet, we need to pay particular attention to all the ingredients contained in a feed, as well as the feed’s nutritional analysis- not just the marketing claims! We also need to remember that a horse’s or pony’s ‘hard feed’ should only make up a small percentage of its diet. We need to consider the role which pasture and hay play in each equine’s intake: from the perspective of calories, starch and sugar. Additionally remember that for multiple health reasons, long-stem fibre (such as that found in hay) should form the basis of their diets. To read more on the importance of fibre and hay, see the articles Fibre, Chewing and Gastrointestinal Health; Why Basics Matter: The Importance of Chewing; Hay, Stomach (Gastric) & Hindgut (Colonic) Ulcers; and Grass, Hay, Fibre and Short Chain Fatty Acids. 

What and how we feed our horses and ponies plays a crucial role in their overall health. In many cases, we can mitigate the risk of severe health conditions, whilst also ensuring that we are giving our equines everything they need to perform at their best and be in the best of health. Clever marketing and loopholes in regulations governing feed claims can make it both challenging and confusing to feed your horse or pony in a way that is best for each individual equine. Seeking independent advice from suitably qualified and experienced nutritionists and equine health practitioners is one of the best investments you can make in your horses’ health and performance. Prefer listening to podcasts or watching webinars to learn more about equine nutrition, gut health, ulcers, immune health and other horse health conditions? Be sure to visit our Media page for plenty of informative recordings.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

In short, it relates to the microbiota of our equines’ digestive systems.

The bacteria, fungi, protozoa, and viruses that colonise the equine gastrointestinal tract (GIT) (collectively known as the microbiota), play many crucial roles in horse health.

These microbes influence digestion, energy and nutrient production, immune health, levels of inflammation in the body, overall GI health, body condition, respiratory health, skin health, metabolic health, reproductive hormones and the production of neurotransmitters (chemicals which influence their mood, temperament, learning, motor control and behaviour).

When the microbiota deviates away from what is optimal, a horse is more susceptible to conditions of inflammation, illness, pathology, GI disturbances including colic, gastric and colonic ulcers, stressed behaviour and diminished nutrient and energy production and uptake.

The large population of microbes that inhabit the equine GI tract are influenced by what our horses and ponies eat. The specific types of microbes become accustomed to what our equines are fed and must adapt to different types of feed. This means that when they eat different types of feed, there are different populations and types of microbes.

Sudden dietary changes induce rapid shifts in this delicate balance of microbes and the byproducts they produce, rendering a horse more susceptible to illness. Whilst this is a broad simplification, the sudden changes in the microbes and their activity are largely indicated in many cases of colic, laminitis and other serious health conditions.

When we add new feeds to a diet or change a horse’s diet- we want to facilitate a gradual change in the microbial population and the products these microbes produce. The best way to do this is to introduce new feeds into their diet gradually over a 7-14 day period, slowly increasing the amounts of the new feed as the microbial population adjusts.

It’s a simple process, which is largely overlooked: something which can save a lot of pain, heartache and expense.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

With plenty of fresh pasture available, it can be tempting to stop feeding or reduce the amount of hay we give our horses. Yet if we want them to have good gastrointestinal (GI) ‘gut’ health, then keeping feeding sufficient hay to them is a must! To learn more about the important role of hay in the diet, visit the article: Hay, Stomach (Gastric) & Hindgut (Colonic) Ulcers.

Green grass is predominantly water and as a result, is low in dry matter fibre. Dry matter fibre is incredibly important for our horses and ponies for a multitude of reasons. Dry matter fibre supports the proliferation of and helps to maintain a healthy GI microflora population. To read more about fibre, see Fibre, Chewing and Gastrointestinal Health.

Dry matter fibre is also needed for the production of short chain fatty acids (SCFAs) also known as volatile fatty acids (VFAs). Short-chain fatty acids are predominantly produced by the fermentation of fibre by the GI microbiome.

These SCFAs have many health benefits, including significant anti-inflammatory and immune-regulating properties. Furthermore, they help to promote the production of specific neurotransmitters (chemical messengers) which help our horses to be calm and relaxed. They have also been shown to help decrease fat accumulation and improve insulin sensitivity (an important consideration with insulin resistance, laminitis and equine metabolic syndrome (EMS)). 

From a direct gut health standpoint, SCFAs play a crucial role to help promote proper GI barrier function- thereby helping to protect against the development of gastric and colonic ulcers. To read more about ulcers, see articles: Hindgut (Colonic) Ulcers in Horses and Ponies; and Ulcers in Horses: The importance of understanding how medications work.

Sometimes the simplest things can make the most profound difference in helping the overall health of our horses and ponies. Adequate fibre is one important dietary measure we can put in place to help promote calm behaviour in our horses, support sound bone and joint health, reduce inflammation, and reduce the risk of laminitis, insulin resistance and EMS.

Prefer listening to podcasts or watching webinars to learn more about gut health, ulcers, immune health and other equine health conditions? Be sure to visit our Media page for plenty of informative recordings.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

And whilst all these can be examples of a horse or pony which is stressed, sources of stress and the effects it has on their body can encompass so much more.

We can actually have horses and ponies who in their nature are very relaxed and settled, yet their body is under significant stress. Stress is a type of change that causes physical, psychological or emotional strain in our horses.

Multiple forms of stress can have a cumulative effect, creating significant demands on the bodies of our horses. As a result of ongoing stress, our equines have increased requirements of particular nutrients.

Stress is also an important consideration in relation to stallion fertility, pregnancy in mares, gastric and colonic ulcers, inflammatory bowel disease (IBD), laminitis, insulin resistance (IR) and equine metabolic syndrome (EMS), chronic infections, bone health and failure to thrive.

Some of the many different sources of stress to our equines include:

• Separation/Isolation
• Injury
• Illness
• Use of certain medications
• Nutritional deficiencies/insufficiencies
• Nutritional excesses
• Travel
• Dehydration and/or withholding water
• Withholding feed
• Weaning
• Pain
• Inflammation
• Intense exercise
• Parasites
• Heavy metal burdens
• Exposure to chemicals, pesticides

What other sources of stress can you think of?

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

For the owner or rider considering taking on an OTTB, careful thought and planning should go into ensuring that the transition from the life of a racehorse to the next phase of the horse’s career is as smooth as possible. Some of the biggest considerations need to be given to changes in the horse’s diet, routine and optimising health parameters. Equipping yourself with knowledge and enlisting the help of suitably qualified professionals can help to realise your horse’s full potential.

Goals and Capabilities as a Rider/Handler

Before even inspecting an OTTB for potential purchase, clearly know what you are wanting in your new horse and your capabilities as a rider. Are you looking for a future show hack with impeccable conformation and looks? Are you looking for a pony club mount that needs to be calm and versatile? Are you looking for a horse with the potential to be a top-class eventer, thereby needing to be very sound, athletic and able to withstand high levels of training? Are you looking to get a cheap yet athletic horse to re-educate and sell on? Knowing the answers to these questions will quickly help to narrow down the horses you inspect for potential purchase and look to undertake a pre-purchase veterinary examination. By clearly knowing your goals, you can save yourself a lot of time and money and are far more likely to choose the most suitable horse.

When taking on an OTTB (particularly one that has come straight from a racing stable environment), honestly assessing your capabilities as a rider is critical. Are you confident and competent enough to safely and effectively manage and deal with an anxious, highly geared horse (whose temperament may or may not change significantly whilst in your care)? Or are you better suited to taking on a more relaxed OTTB or even one that has been off the track for some time and has spent time being re-educated with a different owner? One of the many beauties of OTTBs is that there are so many to choose from and at many different life and career stages- you are bound to find one that suits you perfectly! Be patient and choose wisely.

Vet Check

One of the first things to consider (and often most overlooked) when purchasing an OTTB is getting a thorough vet examination prior to purchase. Musculoskeletal soundness and airway health are two of the most significant considerations. Just like human athletes, racehorses’ bodies are put under strenuous physical demands, with the potential to develop injuries. Due to the hard galloping done by many young horses in training, considerable stress is put on bones, tendons and ligaments. This can lead to soundness issues. A thorough vet examination can help to identify previous injuries or any potential issues which may influence the ability of the horse to be suitable for its intended next career. On radiographic screening (x-ray), many racehorses will have some degree of osteoarthritic changes in their joints. With planning, sound dietary practices and the strategic use of appropriate supplements and management interventions, many of these conditions can be well managed. Furthermore, the fact that many OTTBs transition into their next careers at a relatively young age is advantageous. From a physiological perspective, when given suitable nutrition and support, their body is better able to repair and regenerate than an older horse. Referring back to your goals and what you intend to do with your OTTB is an important consideration here. A past injury in a racehorse which may prevent it from high-level eventing may pose no issues for a horse intended for general pleasure riding.

Suboptimal hoof health is a common finding in the newly transitioning OTTB. This is often due to a combination of poor gastrointestinal (GIT) health (which influences nutrient absorption and the production of essential vitamins such as biotin needed for sound, healthy hooves). For more information on the role of GIT in overall health and the role of nutrition in hoof health see articles: Fibre, Chewing and Gastrointestinal Health; Ulcers in Horses: The importance of understanding how medications work; Hay, Stomach (Gastric) & Hindgut (Colonic) Ulcers; and Beyond Biotin: Optimising Horse Hoof Health.

Routinely being shod in race plates can also compound the problem of poor hoof structure and health. Many racehorses have contracted hooves with under-run heels, long toes and thin soles. Encouragingly, hoof health is an aspect that can readily be turned around in a period of around 8-12 months with appropriate dietary changes and good farriery. Including radiographs of the hooves as part of the pre-purchase examination may be a valuable investment in some horses: x-rays can help to demonstrate what is going on in the hoof and can aid the proactive farrier to trim, shoe and manage the hoof appropriately.

It is important to remember that often racehorses in training will initially go footsore when their shoes are removed and they are left barefoot during a spell. This is especially true of the front feet. Some farriers and owners will choose to keep their horses in shoes. In many cases however, it is advisable for the spelling horse to have an extended period of time being unshod: this helps to positively influence hoof shape and integrity and aids in proper circulation and blood flow to the hooves. Feeding the horse a diet which reduces inflammation, using nutritional supplements (nutraceuticals) and herbal medicine under qualified supervision, and potentially easing the transition to barefoot through the use of padded, removable boots are all beneficial strategies.

Another aspect of the pre-purchase examination should also include an upper airway scope. Respiratory conditions which may be evident when assessing an OTTB include a history of exercise-induced pulmonary haemorrhage (EIPH, more commonly known as bleeding), airway inflammatory disease, and laryngeal hemiplegia (roaring). The first two can generally be well managed with appropriate feeding and supplementation practices and adopting strategies to minimise the inhalation of air particulate matter and dust.

History

Where possible, finding out as much history about the horse as possible can help to make a smooth transition to the next phase of its career. For a horse coming straight off the track, contact with the trainer and/or stable manager can help provide you with valuable information as to any health or injury concerns with the horse, the dates it was last vaccinated and drenched (de-wormed), any medications and/or supplements it may have been receiving, its current diet and any quirks, habits or temperament considerations to take into account. Having said this, it is also important to remember that when a horse is put in a new environment, some of the aforementioned things may change! For example, a horse that was previously often irritable can become much calmer with a more natural diet and living environment. Similarly, horses which may have been very picky eaters whilst in training often become very good eaters once their GIT health has improved and the stress of the training environment has been removed.

Diet

The majority of diets fed to thoroughbreds in training are not conducive to optimal GIT health and function. Practices vary between trainers and stables, but most often, horses in training are fed two or three large grain and/or concentrate-based meals per day. Grass and/or lucerne hay are often provided in limited amounts. Many trainers do not have the luxury of turning horses out to graze. This puts the horse’s digestive system under strain and increases the likelihood of many health issues including ulceration throughout the GIT (gastric and colonic ulcers), colic, disturbances in the GIT microflora (bacterial balance of the digestive system), hindgut acidosis, suboptimal ability to utilise feed properly and nutritional deficiencies/insufficiencies. The addition of high cortisol levels produced by the horse in response to stress and high-intensity exercise further compromises GIT health and digestive function. To read more about the contributors and effects of stress in our horses see: Stress in Horses: Why it isn’t always obvious.

Horses, by nature, are designed to be constantly moving about and grazing high-fibre roughage. This is important as the stomach of the horse is relatively small in volume and has little capacity to expand. As a result, small amounts of feed which are consumed often are digested much better than the large volume feeds given a couple of times per day. The constant grazing a horse does in its natural environment also ensures that there is a physical buffer in the stomach to protect against the breakdown action of hydrochloric acid and digestive enzymes. These substances are constantly produced in the horse and are essential for proper digestion, as well as immune function. To read more, visit: Ulcers in Horses: The importance of understanding how medications work. Grazing and chewing also stimulate the production of saliva. Saliva serves many important functions in the horse, including releasing bicarbonate ions into the stomach (which also protects the stomach lining, another smart natural mechanism of the horse to protect against ulcers). To learn more about the benefits of grazing, visit: Why Basics Matter: The Importance of Chewing.

Sudden changes in feeding practices (even those that are beneficial to the horse) can increase the risk of colic and other complications. This is thought to be largely attributed to rapid changes in GIT microflora in response to the feed offered. Finding out the horse’s current diet prior to purchasing can help to make smooth transitions to a more fibre-rich feed, whilst ensuring the gut microflora change at an appropriate rate. It is advisable to make the transition of feeds gradual (over a period of 12-14 days) to help best facilitate this.

Whilst horses who come directly out of training will have been maintained on high-energy rations, their relative energy needs during their initial transition into an OTTB will be much lower. Furthermore, if GIT health is optimised as part of their transition (through feeding, management practices and appropriate supplementation), they will be better able to use fibre rich feeds (ie pasture and hay) as energy sources. This is made possible through bacterial fermentation in the hind gut (helpful microbes in the large intestine break fibre down into short-chain/volatile fatty acids, a high source of energy for the horse). It is important to remember that whilst a horse’s actual energy needs may be much lower than when they were in training, their need for specific minerals, vitamins and protein may remain relatively high. Without the excess demands of training and racing the body is in a prime position to help address and heal any niggling injuries, musculoskeletal damage or immune health challenges. To find out more about nutrient requirements and the role of protein for horses visit Nutrient Requirements for Horses: Fortified Feeds and the need for Supplementation; The Importance of Protein. These are commonplace in any athlete involved in demanding sports. To facilitate optimal healing and health, is essential to ensure that the OTTB receives at a minimum the recommended dietary intake of minerals and vitamins, in addition to good quality protein sources. A good quality balancer feed or supplement, in the addition to sufficient pasture, hay and lucerne hay (where appropriate) will help to meet these needs.

Some people find challenges in putting condition on their OTTB and/or the horse being picky with their feed. This is most often due to irritation of GIT, use of ulcer medications and non-steroidal anti-inflammatories (NSAIDs) such as ‘bute’ (PBZ), and the diet racehorses are commonly maintained on,. These factors can all significantly compromise gut integrity and health. Add to this the stress of a new environment and the change in the horse’s routine and it can take a little time for the horse to adjust. Whilst the prescription of appropriate nutritional and herbal supplementation can help immensely in these cases, basic management practices including turning the horse out to graze, the provision of sufficient roughage (hay, pasture), and keeping the OTTB  with a sensible paddock mate are all effective starting points owners are encouraged to implement. One of the most common mistakes that can be made when wanting to put weight on a newly acquired OTTB is to continually increase the ration of grain or high-energy concentrate feed, without the provision of sufficient roughage and fibre. This contributes to additional compromises in the integrity of the GIT lining and further shifting the hindgut microflora away from that which promotes the best utilisation of feed and energy. As a result, the cycle of struggling to gain weight is perpetuated, and often leads to frustration as the horse seems to take an extended period of time to ‘let down’ and gain condition. To read more about horse’s who struggle to put on condition, visit the article: HELP! My horse won’t put on body condition.

Down Time

One of the best things you can do as an owner of a newly transitioning OTTB is give it some much needed ‘down time’. The majority of racing stable environments are far removed from what is a natural for the horse. Like humans constantly under work deadlines, family demands and everyday pressures, horses too routinely experience stress. This stress is manifested in many forms, primarily driven by changes in levels of the stress hormone cortisol (which can lead to reduced immune function, high levels of inflammation, changes in temperament and behaviour, and reduced capacity to recover). Additionally, the constant physical demands of training and racing can lead to ongoing musculoskeletal ‘niggles’- aches, pains and minor injuries. A period of 4-8 weeks, turned out in the paddock, fed a fibre-rich diet, and not in the demands of work or being fussed with is one of the most beneficial things you can do to help the newly transitioned OTTB. It helps the horse to mentally wind-down, aids in the restoration of GIT health, gives any small niggles the chance to heal, and lets the horse settle into a new environment and freshen up. Just like humans, horses too need holidays. Simply giving them time out before asking new demands from them in their new career, can help them get off to the best start. 

Temperament

A significant (and often highly variable and unpredictable) consideration in the OTTB is temperament. This can be a challenge when acquiring a new horse, as it is difficult to know exactly how much is ingrained behaviour and the horse’s natural tendency, compared to how much it is a result of the environment the horse has been in, the feeding practices and GIT health. An important consideration to note is that 70-80% of the neurotransmitters (the chemicals which influence mood, temperament, behaviour and learning) are produced in the GIT. There are clear links between GIT health and levels of anxiety, mood changes and behaviour. This is useful to take into account: an OTTB which has struggled with compromised gut health in training and may be nervous, edgy or readily spook can change significantly when GIT health is addressed. A combination of appropriate supplementation and feeding, combined with appropriate ‘down time’ can really significantly impact the behaviour of an OTTB for the better. It routinely plays a role in why many horses that are temperamental/nervy/anxious in training become more relaxed away from the stable environment. Keep in mind too, that the actual environment the horse is kept in also plays an important role.

Monitoring and Progress

From a basic health standpoint, once the new OTTB has arrived and settled, it is wise to measure temperature, respiratory and heart rates at roughly the same time each day for a week to establish what is ‘normal’ for your horse. Record these and keep on hand (using the notes section on your mobile phone can be great, otherwise written on a whiteboard or somewhere easily accessible). This information is incredibly helpful in the instance that your horse may become unwell: you know what is ‘normal’ and healthy for your horse, helping to implement appropriate strategies in a timely fashion.

Taking photos of your horse from the side and back (safely), on a fortnightly or monthly basis is a simple tool to monitor body composition changes and progress. The same thing can be done with their hooves front and side-on, in addition to picking the hoof up and taking pictures of the sole and frog. It can be incredibly rewarding to look back over a 4-6 week period and notice the subtle improvement in body condition. Horses can make significant progress in gradual increments, which may be missed when you are seeing the horse on a daily basis. By having photo evidence on hand, you are able to make a more objective assessment. Keep in mind that changes in hoof shape and quality will be much slower to notice: front hooves take a full 8-12 months to grow from the coronary band to the toe.

The majority of horses in training are maintained on a routine drenching (deworming) schedule. Given our current state of understanding in relation to resistance to worming products, it makes sense to adopt a strategic drenching approach. In order to implement this safely and effectively, taking routine faecal samples to be sent off for testing are encouraged. Doing this at the commencement of ownership can help to provide guidance to the most effective drenching requirements of your horse. For more information on drenching/deworming visit the article Drenching/Deworming with Panacur.

Conclusion

Like most worthwhile things in life, effectively transitioning a racehorse to an accomplished OTTB takes time and patience! Knowing your capabilities as a rider and having clear goals as to what you want to achieve with your new mount are important starting points. Enlisting the expertise of suitably qualified professionals and equipping yourself with the knowledge of best practices can help make for a smooth and rewarding journey. Choosing an OTTB can make for one of the most gratifying experiences as a horse owner and rider. Careful consideration, planning and attention to detail can ensure you give your horse every chance to excel in its new phase of life.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

The left and right hemispheres of the human brain are densely interconnected by millions of white-matter fibre tracts. These tracts allow humans to generalise a task from one side of the body to the other. That is, if we learn to do a task using our right hand, that information can be generalised to allow us to replicate the same task in our left hand (that’s not to say it’s always easy, as we are generally dominant on one side, but the concepts for how to do it are already encoded in our brain!) In fact, the brain’s wiring criss-crosses: the right side of the body is actually controlled by signals originating in the left side of the brain and vice versa.

The way the horse’s brain works is very different in this regard. The equine brain has a limited capacity to generalise and apply what is learned on one side of the body to the opposite side. Each side must be approached and learnt independently. It is crucial to train a horse in a balanced fashion- repeating the same tasks on both the near (left) and off (right) sides. In addition to the neurological component of performing tasks on both sides, doing so will also help to promote more balanced musculoskeletal strength and development on both sides.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

The horse that fails to thrive can be one of the most frustrating challenges for owners, trainers, breeders and riders. The horse who no matter how much you feed it, how many times you drench (worm) it, how long it stays on medications for gastric ulcers or how many supplements you add to its feed- it still fails to put on significant weight, looks lacklustre and just doesn’t thrive like it should. Not to mention costing you an absolute fortune to keep! It’s common (and reasonable) to think that the more you feed the horse (particularly high energy grains and/or concentrates) the more weight and body condition it should gain. If a horse consumes excess calories (energy intake) relative to energy expenditure (calories out) then we would expect weight gain to occur.  And whilst the energy equation is an important consideration in such horses, if it was the sole reason in all cases, then horses that fail to thrive would be in the minority. The number of clinical cases where the primary reason for the owner contacting me is to help their horse gain weight suggests that this certainly is a common complaint. So why does it occur and what can we do to help these horses put on condition and thrive?

Potential contributors to failing to put on weight/condition

Like many health challenges and conditions in our equines, there are multiple factors which can contribute to failure to put on weight. Generally, it comes down to a combination of factors, not just one single reason. In the absence of a serious health condition in our horses, which should be ruled out by a thorough case history and veterinary diagnostics if indicated, the below are the most common reasons I see in clinical practice contributing to horses failing to thrive:

• Poor gastrointestinal (GI) health
• Insufficient fibre (particularly long-stem fibre in the diet)
• The volume of ‘individual hard feeds’ (ie grains and concentrates) too large per feed
• Horses being fed the wrong ‘type’ of feed
• Nutritional insufficiencies/deficiencies and imbalances (largely minerals and sometimes protein) which influence metabolic function (for example thyroid function)
• Side effects of certain medications (such as antibiotics, non-steroidal anti-inflammatories and corticosteroids)
• The use of gastric ulcer medications
• High stress levels in the horse
• High levels of pain in the horse
• High levels of inflammation in the horse
• Poor dental health
• High parasite load
• Inappropriate/insufficient exercise stimulus
• Windsucking/Cribbing

Poor Gastrointestinal Health

This is by far the most significant contributing factor relating to failing to put on/maintain weight in clinical cases I see. Poor gastrointestinal health can relate to compromised integrity of the cells lining the GI tract (gastric mucosa), imbalances in the microflora (the population of microbes, largely bacteria) of the GI tract and inflammation of the GI tract. These issues generally occur together. Gastric and/or colonic ulcers are also relevant in many cases, as a result of changes in the aforementioned factors. Many things can contribute to poor GI health (such as insufficient long-stem fibre in the diet, the use of certain medications- including ulcer medications, stress, travel, dehydration, just to name a few). To read more on these topics see articles:Hay, Stomach (Gastric) & Hindgut (Colonic) Ulcers; Hindgut (Colonic) Ulcers in Horses and Ponies; Inflammation & Non-Steroidal Anti-Inflammatories in Horses; Ulcers in Horses: The importance of understanding how medications work; Ulcer Medications: What Nobody Tells You and What You Need To Know; Fibre, Chewing and Gastrointestinal Health.

Insufficient Fibre

Sufficient dietary fibre is crucial in the diet of our horses’ and ponies’. In addition to promoting good GI health (see paragraph and articles above), fibre also serves as an important energy source in our horses. It’s easy to think that a horse who needs more condition needs more calories (the relative energy content of fibrous feeds such as hay is much lower compared to grains and most concentrates). Yet in addition to promoting healthy GI microflora, fibre serves as an important energy source for these microbes. They ferment the fibre to produce short chain fatty acids (SCFA) also known as volatile fatty acids (VFA). These fatty acids are a valuable ‘cool’ energy source for our horses, in addition to producing important anti-inflammatory compounds and promoting and maintaining a healthy GI tract. If we don’t feed our horses sufficient fibre, the lose out on these benefits. We can’t successfully ‘out-supplement’ insufficient fibre in our horse’s diets!

Volume (size) of ‘hard’ feeds

Horses have very small stomachs relative to the size of the animal, accounting for only 10% of the volume of the digestive system. Our horses are designed to be constantly ‘grazing’, which allows optimal digestive function. When our horses are fed large meals, which require relatively little chewing (such as grains and concentrates) the food passes through their stomach quickly. This results in the feed entering the small intestine largely undigested. Consequently, the horse isn’t able to extract the energy and nutrients from the feed properly, and the undigested feed enters the hind-gut, where it ferments and causes changes in the pH and microflora population. Whilst fibre passes largely undigested into the hindgut and is naturally fermented here (and provides significant benefits because of this), no other feed should be fermented in the hindgut. In a mature horse, individual meal sizes should be no more than 2.3kg (5 pounds) in volume.

Horses being fed the wrong ‘type’ of feed

Feeding horses a commercial pelleted or mixed concentrate feed can be an efficient way to help meet nutrient requirements. However, not all pelleted or commercially manufactured feeds are created equally. They vary vastly in ingredients contained, nutrient and energy content. Feeds on the market range from low calorie mineral balancers to high energy concentrates. Feeding a low calorie balancer (even in large quantities) won’t significantly contribute to energy intake in our horses. Hence, selecting an appropriate feed is really important to help the horse failing to thrive.

Feeding large amounts of hard-to digest grains or concentrates is also a common occurrence in the horse failing to thrive. On paper it can make logical sense to feed the lightly conditioned horse plenty of grains as they are generally high in calories. Yet these grains aren’t always readily digested, and feed that isn’t digested properly won’t help to condition our horses well. For example corn (even cracked/rolled corn), despite being relatively high in starch and calories has very poor digestibility. This means our horses are not able to efficiently utilise the calories in it, in addition to it also adversely effecting GI microflora, compounding the whole problem. Remember that many high calorie concentrate/manufactured feeds contain large amounts of grains.

Nutritional insufficiencies, deficiencies and imbalances

In addition to sufficient energy (calories), our horses need protein (made up of amino acids), fats, vitamins and minerals to serve multiple different functions in the body. Sufficient protein is needed to aid in muscle hypertrophy (growth) thus plays an important structural role in conditioning horses. Additionally, the amino acids found in protein are needed for the production and activity of digestive enzymes. Digestive enzymes help our horses to properly break down their feed, allowing for the absorption of energy and nutrients. Along with fats, vitamins and minerals, protein also plays key roles in supporting metabolic function and the production of key hormones needed to promote healthy growth in our horses. Insufficiencies or relative imbalances in these key nutrients can both directly and indirectly affect a horse’s ability to put on body condition.

Side effects of certain medications

Particular medications commonly used in our horses have the ability to impact their body condition. Antibiotics, non-steroidal anti-inflammatory drugs (NSAIDs) such as phenylbutazone (bute) and flunixin (Banamine), and corticosteroids all impact a horse’s GI microflora and the integrity of their stomach lining. Lesser considered medications include omeprazole and ranitidine (the key active ingredients in most ulcer medications), which interfere with a horse’s ability to properly digest and absorb their feed, and also impact their GI microflora. Other medications such as diuretics (Furosemide/Lasix) influence the absorption, metabolism and/or excretion of key nutrients needed for healthy metabolic function and conditioning in a horse. Medications such as Clenbuterol (Airway Gel, Claire Gel) and synthetic thyroid hormone (L-Thyro) directly influence metabolic rate in a horse, commonly resulting in weight loss or inability to put on sufficient condition.

The use of gastric ulcer medications

It can seem quite ironic- medications commonly used to help aid in healing of gastric ulcers can actually compound the challenge of gaining condition in the poor doer. Gastric ulcer medications work by shutting down the production of hydrochloric acid. Yet without adequate hydrochloric acid our horses can’t properly digest, absorb and metabolise their feed and nutrients in it. As a result, feed passes largely undigested in to the hindgut, adversely impacting GI microflora. To learn more about the actions of ulcer medications, visit the articles: Ulcers in Horses: The importance of understanding how medications work; Ulcer Medications: What Nobody Tells You and What You Need To Know

High stress levels and/or high levels of pain

High and/or continued levels of stress and/or pain in our horses results in changes in the production of the hormone cortisol and chemicals which promote inflammation in the body. This in turn commonly results in the breakdown of muscle tissue, leading to difficulty putting on/maintaining condition- largely lean muscle mass (the kind of condition we want on our horses). Changes in GI blood flow and microflora balance also commonly occur as a result of stress, further impacting digestion. Additionally gastric and/or colonic ulcers, which frequently develop as a result of chronic stress, can further compound the problem. To read more on the systemic effects of injury and pain, see the article: Injury and Pain in our Horses and Ponies

High Levels of inflammation

Long-term (chronic) inflammation in horses reduces the synthesis of muscle protein. It also increases the rate at which muscle proteins break down. Special types of molecules called inflammatory cytokines, which are  involved in cell signalling during inflammation, trigger the release of cortisol and particular neurotransmitters (chemical messengers in the body). The combination of cortisol and these neurotransmitters disrupt cellular metabolism and alter a horse’s metabolic rate, which can heighten the breakdown of muscle tissue.

Poor dental health

Dental health can influence a horse’s ability to put on and/or maintain body condition in several ways. Sharp edges on teeth, loosened teeth, tooth infections, tooth loss or uneven wear of teeth can contribute to pain and compromised ability to chew feed well. Properly chewing feed is an important part of initiating digestion in the horse, allowing it to adequately utilise feed.

Less commonly considered aspects of dental health in our horses are gingivitis (gum inflammation) and periodontitis (where the inner layer of the gum and bone pull away from the teeth and cause pockets of air between the gums and teeth). These conditions affect horses in a similar way to humans. Gingivitis usually precedes periodontitis and begins when bacteria in the mouth proliferate around the teeth and gums. The build-up of large numbers of bacteria that attack the gingiva or gums leads to inflammation. It’s important to note that as the disease progresses and the gums become swollen and bleed, bacteria are able to enter a horse’s bloodstream and travel around the body. This can result in high levels of systemic inflammation and adverse changes to gut microflora, thereby influencing overall health and digestive function. To read more on the systemic effects of dental health in horses, visit: Bad Breath in Horses

High parasite (worm) load

Did you know that there are more than 150 types of parasites that affect horses? The four most common types are strongyles, ascarids, tapeworms and bots. High numbers of parasites (a high parasite load) can contribute to inflammation throughout our horses’ digestive tracts, damage to the lining of the stomach and intestines and gastric and/or colonic ulcers. These inhibit our horses’ ability to properly digest and absorb their feed.

Simply drenching/worming our horses more frequently is generally not the answer. This can contribute to increased parasite resistance to anthelmintics (drugs used to help kill parasite), in addition to impacting a horse’s GIT microflora. Best practices involves the use of appropriately timed faecal egg counts, assessing parasite burden in the horse, and strategic drenching using appropriate anthelmintics. For more information on best drenching/deworming practice visit: Drenching/Deworming with Panacur

Inappropriate/insufficient exercise stimulus

For our horses to develop and maintain muscle mass and body condition there are several important components. Good GI health to properly digest, absorb and metabolise nutrients needed for protein synthesis and muscle cell growth (hypertrophy) are essential. Our horses also need to be fed a diet which meets both their protein and calorie requirements. An easily overlooked factor is appropriate type and quantity of exercise. Our horse need to be engaging the correct muscles in the correct frame to develop good muscle growth and conditioning. Horses who are not exercised adequately, and/or not engaging the correct muscles when working will fail to capitalise on their ability to develop good muscle mass. Horses who are spelling, injured or on box/stall rest will likely not maintain their best muscle mass. A useful analogy can be to think of a person who wants to gain muscle mass or muscle definition. If they eat plenty of protein and calories, yet spend their day largely inactive, sitting on the couch and not exercising, they will fail to properly develop optimal muscle strength and definition. On the other end of the spectrum, someone who trains really hard in the gym, but fails to eat enough quality food to fuel their training will not maximise muscle development gains. It takes a combination of both training and proper fuelling! To read more, visit: What Supplements are best for building Topline?

Windsucking/Cribbing

Windsucking (also known as cribbing or crib-biting) in horses is a stereotypy, or repetitive behaviour which can significantly impact a horse’s ability to put on or maintain weight.

In addition to weight loss and overall poor condition, wind sucking can result in abnormal development of muscles in the neck, and excessive wear of teeth- affecting a horse’s ability to chew properly. Cribbing can interrupt a horse’s daily routine, occupying several hours per day. This reduces time spent grazing and foraging. Cribbing is commonly associated with digestive discomfort, gastric ulcers and imbalances in specific neurotransmitters- all factors which are known to influence a horse’s ability to properly digest, absorb and metabolise their feed. To read more about windsucking/cribbing visit: Why do horses wind suck and crib bite?

The horse who fails to gain or maintain adequate weight and muscle mass can be frustrating. Whilst it is common to look at one likely reason for their weight struggles, there are generally several factors contributing to the state of the horse’s health. The good news is that when contributing factors are properly identified and addressed, the horse who once had difficulty putting on and/or maintaining weight can flourish. Additionally, by correcting the underlying issues, you are helping to facilitate the best health and performance in your horse.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

From a dietary perspective, it is thought that horses may chew wood when they aren’t consuming enough fibre in their diet. This can happen to horses who are kept in stables or in paddocks. It’s common to think that horses who are grazing pasture are consuming enough fibre to meet their needs, but grass is relatively low in fibre. Unless sufficient hay is fed in addition to grass, horses will likely fall well short of their fibre requirements. Adequate fibre in the diet is incredibly important for optimal gastrointestinal (GI) function, promoting balanced microbial flora of the GI tract, preventing ulcers, supporting immune function and supporting neurotransmitter production (just to name a few of its roles!). To read more about the importance of fibre for horses and ponies visit the articles: Hay, Stomach (Gastric) & Hindgut (Colonic) Ulcers; Fibre, Chewing and Gastrointestinal Health; Why Basics Matter: The Importance of Chewing.

Lignophagia may also be due to boredom (which again, can commonly arise due to not enough grazing). Left unaddressed, chewing wood may develop into a stereotypy behaviour. As with any abnormal behaviour it should be viewed in a holistic context.

Other reasons for a horse to chew wood may be due to poor GI health- particularly imbalances in the microflora population of the digestive tract. This is commonly associated again with insufficient fibre in the diet (although there are many other factors which may also contribute). Specific micronutrient insufficiencies/deficiencies may also play a part in lignophagia. Weather conditions can play a role in the habit in some horses, with research showing that horses are more likely to gnaw on wood during wet, cold weather. This may be due to an instinctive urge for more roughage in their diet as temperatures fall.

Identifying and addressing the reasons why a horse is chewing wood is important, as the behaviour comes with its own set of health risks in our horses and ponies. Chewing wood places unnecessary wear on a horse’s front teeth, which can make chewing less effective and hinder digestion. They may also ingest sharp wood fragments, which can injure your horse’s digestive system. In rare cases, they may also lead to the formation of enteroliths (intestinal stones that form within the colon and can obstruct the intestine, resulting in colic).

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

Altrenogest, commonly referred to as Regumate or Readyserve (two of its trade names) is a synthetic progesterone product used to suppress oestrus in mares (and often used to help ‘maintain’ pregnancy in ‘problem’ pregnancy mares). It is the first choice by many horse people to help ‘control their marey-mare’.

Whilst the health issues associated with the use of altrenogest in horses are extensive, it’s well worth being aware of health implications in humans.

Scarily, altrenogest is routinely viewed and handled as a relatively harmless substance. Yet this drug can cause significant hormonal and health problems to humans who come into contact with it. Altrenogest has been widely reported to the Food and Drug Administration (FDA) for its adverse effects in both men and women.  Exposure is most commonly reported following drug contact with the skin, but it is important to note that some reported exposures occur in conjunction with touching product residue on barn surfaces, equipment, and treated animals. Put simply, you don’t even directly have to handle the drug to suffer adverse health effects from it.

The most significant noted health implications of human exposure to altrenogest involve reproductive system issues, including abnormal menstrual cycles in women (changes in bleeding frequency, pattern and amount). Girls as young as 14 years old have been effected- an alarming consequence. In men, decreased libido has been reported. Headaches, fever, abdominal pain, nausea, diarrhoea, vomiting and skin rashes have also been associated with exposure to altrenogest.

The labelling for all altrenogest products include warnings against human exposure as the hormone is readily absorbed through intact skin. It’s easy to think that wearing latex gloves will protect us from the harmful effects of this medication. But this is a misconception: latex allows the passage of altrenogest through it, which can then penetrate the skin. Once altrenogest has been spilt on the gloves and soaked through, it is then more readily absorbed by the skin compared to being able to pass back through the glove. Essentially this practice creates an ‘altrenogest patch’.

When it comes to the use of altrenogest in fillies and mares, it is important to remember that the causes of hormonal problems and imbalances may be due to many factors. Feeding practices, nutritional status, inflammation, body composition, gastrointestinal health and stress levels are all very important, yet are commonly overlooked. Appropriately prescribed herbal medicines and nutritional supplements, alongside sound dietary and management practices can significantly help the ‘hormonal’ mare or filly. Understanding why a mare or filly exhibits such behaviour is really important to promote overall best health and performance. Simply manipulating hormone levels through the addition of synthetic progesterone rarely helps to address the cause: it simply bandaids it.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

In many cases, the source of pain in our horses can be diagnosed and attributed to a specific injury or degenerative process such as osteoarthritis. Yet the pain itself rarely occurs in isolation. Other physiological changes occur which influence the sensations our horses experience and their perception of pain.

In the case of acute injury in our horses (think muscle, tendon or ligament damage) there is associated inflammation and commonly oedema (swelling). There are also changes in the types and balances of neurotransmitters produced (chemicals which influence temperament, mood, behaviour and pain perception) and alterations in cortisol levels. These initial changes occur to help the body facilitate healing of the damaged tissue- and to a certain extent are desirable and necessary.

When injury or inflammation becomes prolonged however, the body’s responses become dysregulated. What started out as a normal healing response becomes dysfunctional and can lead to chronic pain and tissue degeneration. Further alterations in neurotransmitter production and function occur- resulting in heightened pain perception in our horses. There is often a concurrent increased production of neurotransmitters associated with anxiety: think of the horse in pain who is always on edge. The anxiety experienced with chronic pain can lead to the experience of greater pain intensity: physiologic changes within the neurological system cause a phenomenon of central sensitisation to pain. Furthermore, stress and anxiety can promote the release of pro-inflammatory mediators, which cause further damage to tissue and more pain.

Contrastingly, it is common to see horses in chronic pain who experience depression. These are the horses which become withdrawn. The ones who you can look at their eye and know they are not ok. As a result of chronic pain, neural pathways in the brain change. Even when tissue damage is resolved, our horses can still experience real pain. The use of NSAIDs cannot help with this.

In the case of injuries- particularly those that are long-standing, horses can ‘guard’ the painful area, hold excessive tension in muscle, fascia and other tissues and change their biomechanics and movement patterns to cope with the pain. Appropriate body work and rehabilitation exercises are an important part of an integrated approach to help facilitate healing and prevent further compensation or injury moving forward.

Pain and inflammation may contribute to certain nutritional deficiencies and/or insufficiencies in our horses and ponies. This is particularly true of chronic pain. Both excesses and insufficiencies of specific nutrients can also increase pain perception and inflammation and are a key consideration to address.

Whilst providing appropriate pain relief is absolutely paramount when indicated, it is important to remember that in many cases, the use of anti-inflammatories alone will not adequately address all the causes of the pain. We also need to be aware of the changes these drugs make to the integrity of the gastrointestinal tract and associated microflora, which in turn influence inflammation, pain perception and systemic health (to read more see articles: Inflammation & Non-Steroidal Anti-Inflammatories in Horses; Anti-Inflammatory Drugs and Recovery). 

Effectively helping horses or ponies in pain, particularly long-standing or chronic pain should encompass a multi-faceted approach. Addressing neural pathway involvement should be a primary consideration, in addition to identifying and rectifying imbalances in specific neurotransmitters. Appropriately prescribed herbal medicines and nutraceuticals can help to facilitate this. The role of nutrition in the equine suffering from pain is also important: ensuring that no nutritional excesses, deficiencies, or insufficiencies are increasing their pain experience. Where appropriate, body work and rehabilitation exercises should also be incorporated. Unless the causes of pain are properly addressed, our horses will potentially continue to go through the cycles of discomfort. Understanding how and why the pain has occurred is important to help effectively treat and resolve it.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

A commonly used ‘natural’ supplement for ‘marey’ mares is the herb Vitex agnes castus (commonly referred to as Vitex, Chasteberry or Chaste tree).

During the estrus phase of a mare’s oestrus cycle (the time when a mare is ‘in season’), oestrogen levels peak- which can cause behavioural changes and increased sensitivity in our mares and fillies.

Vitex is an herb which can help to increase progesterone levels. Increasing progesterone levels can help to counter some of the signs and symptoms associated with excessively high oestrogen levels. Yet this herb definitely isn’t suitable for all ‘marey’ mares and fillies and can actually make behavioural issues worse.

Like many herbs, Vitex has more than one therapeutic action. In addition to modulating progesterone levels, it has dopaminergic actions: it increases the levels of the neurotransmitter dopamine. Dopamine is a stimulant neurotransmitter, and whilst it is common to see horses in clinical practice with low dopamine levels, there are also horses who have naturally higher dopamine levels. Those with high dopamine levels can demonstrate behaviours of irritability, hyperactivity, hypersensitivity and/or aggression.

Giving vitex to mares who already have high dopamine levels can make the whole problem worse. In clinical practice, vitex is rarely an herb I use in cases of hormonal mares and fillies.

Appropriately prescribed herbal medicines can be incredibly valuable, but understanding their totality of pharmacological actions is crucial to ensure we help our horses and not make a problem worse. It’s also an important reminder that herbal medicines are best prescribed by a suitably qualified and experienced practitioner- not just purchased online or off the shop shelf.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

What we know from current research is that simply giving our horses tryptophan as a supplement doesn’t help promote calm behaviour- in fact, it may do the very opposite. Low doses of tryptophan given to horses actually promotes excitement, whilst high doses have been shown to reduce endurance capacity and cause haemolytic anaemia. In either case, hardly helping with overall health and performance.

The reasons for the effects of tryptophan supplementation on horses are likely multifaceted. We know that responses to tryptophan are species dependent- whilst it can be helpful in humans and some animal species, the same cannot be said for horses.

It is important to remember that very few nutrients act in isolation. For tryptophan to be converted to serotonin, it has to go through several metabolic processes. Each of these processes requires key nutrients to facilitate the conversion. Without sufficient nutrient levels and good gastrointestinal health to facilitate this, the conversion and metabolism of tryptophan are effected.

We also need to remember, like many facets of health- there is a sweet spot between not too little and not too much. The same is true for serotonin- too little, and our horses can be anxious, too much and they can become agitated.

The take-home message is that whilst some supplements can be incredibly useful, not all are. We can better promote healthy neurotransmitter levels (such as serotonin) by ensuring our horses are receiving a balanced diet providing all key nutrients in appropriate quantities and forms. Additionally, we want to ensure that we’re promoting optimal gastrointestinal health, as this in turn helps to facilitate both healthy nutrient production and neurotransmitter levels.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

Horses and ponies are able to synthesise (make) their own vitamin B12 when they have a healthy balance of hindgut microflora, sufficient fibre in their diet and a suitable mineral intake- particularly adequate dietary cobalt.

What is commonly overlooked is the fact that injectable vitamin B12 is rapidly and nearly completely excreted via bile into a horse’s manure. In essence- they can’t use or absorb this form of B12…it just makes for expensive poo!

Having a healthy digestive system is incredibly important in our horses and ponies to promote many facets of their health: good hoof quality and growth, optimal metabolic and immune function, the production of neurotransmitters (natural chemicals) which help to promote calm behaviour and reducing inflammation.

The production of optimal levels of vitamin B12 to aid in athletic performance are just another reason why we need to focus on sound feeding and management practices and the judicious use of medications in order to promote good gastrointestinal and overall health. It is also an important reminder that we often just can’t out supplement poor dietary practices.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

The signs and symptoms of both gastric and colonic ulcers can be very similar, and both can be very general and non specific. In the case of gastric ulcers, vets are able to perform a gastroscope to confirm (or exclude) the presence and severity of ulcers. Unfortunately, the tools available to diagnose hindgut ulcers are limited and don’t necessarily give us the same definitive answers.

Something that is really important to be aware of is that when colonic ulcers are suspected and stomach ulcers have been ruled out, the use of ‘ulcer medications’ (oral medications containing the active ingredient omeprazole or ranitidine and injectable esomeprazole) are NOT indicated. Ulcer medications stop or significantly reduce the production of hydrochloric acid in the stomach. These medications may actually contribute to worsening of the problem through interfering with proper digestion and causing more undigested feed (which should begin digestion in the stomach both directly and indirectly through the action of hydrochloric acid) to enter the hindgut and ferment. The only thing that should ferment in the hindgut is fibre! Other feeds fermented in the hindgut can contribute significantly to inflammation, damage to cells lining the hindgut and adversely impact delicate balances of microflora.  Hydrochloric acid is NOT produced in the hindgut and does NOT contribute to hindgut ulcers.

It’s worth remembering that both gastric and colonic ulcers can exist concurrently, and that simply ruling out gastric ulcers as a cause of a horse’s signs and symptoms doesn’t necessarily mean that their gastrointestinal (GI) health is good. The successful treatment of gastric and/or hindgut ulcers should involve a comprehensive dietary and management plan (both during the healing phase and long-term), and identify and address the factors which have contributed to the development of poor GI health in the effected horse.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

The horse or pony prone to laminitis can be a challenge to keep healthy. Poorly managed or severe episodes of laminitis can lead to devastating consequences. Diligence and modification to the diet and management regime of a horse or pony at risk of or with laminitis are required to prevent further deterioration or episodes of the condition and keep the equine in the best health possible. If a supplement on the market claimed to prevent acute episodes of feed related laminitis AND didn’t require changes in the way we feed and manage our horses and ponies, then surely that would be great? On the surface, maybe, but when we understand about HOW such a product possibly prevents laminitis and the potential long-term health repercussions, then stopping to reconsider its use is certainly warranted. Especially when one of the leading equine veterinary authorities in the world completely ban its use.

One widely promoted and used product on the market contains the active ingredient Virginiamycin. Virginiamycin is an ANTIBIOTIC.

It is well known, researched and demonstrated that antibiotics have an adverse impact on gut health through several mechanisms. They kill off not only ‘bad’ but ‘good’ bacteria which play many essential roles in our horses’ and ponies’ digestive systems. Amongst other functions, these healthful bacteria help to break down the fibre in hay and roughage to produce ‘cool’ energy for our horses; they produce substances which play a role in preserving the lining of the gastrointestinal tract (GIT) helping to reduce inflammation and protect against ulceration; they produce B group vitamins, biotin and vitamin K- essential for energy production, hoof health, reproductive health, bone health and strength, and recovery from exercise to name a few; they are intimately involved in the production of neurotransmitters (chemical messengers which influence our horses’ moods, temperament, behaviour, gut motility, etc); and these helpful bacteria also play a crucial role in proper and healthy immune function. Furthermore, compositions of specific ‘good’ GIT microflora have been shown to play an important role in metabolism, blood glucose control and insulin sensitivity: all which may have a protective effect in the horse or pony at risk of insulin resistance (IR) and equine metabolic syndrome (EMS). It is well known that horses with IR and/or EMS are at an increased risk of laminitis.

Antibiotics are also known to increase intestinal paracellular permeability and promote intestinal barrier dysfunction- sometimes referred to as ‘leaky gut’. Episodes of laminitis are commonly a sequelae of the above.

Through the use of antibiotics, bacteria (both ‘good’ and ‘bad’) are kept in check (although with increasing antibiotic use and levels of antimicrobial resistance eliminating the ‘bad’ bacteria is becoming increasingly more difficult) thereby keeping some of the triggering factors to laminitis episodes at bay.

We KNOW that diet has a significant influence in the majority of cases of laminitis. We also know that the integrity of the GIT lining also plays a paramount role. In horses with poor digestive health (which is common and can be caused by many factors- visit the Articles section on Optim Equine’s website to read more) high grain/carbohydrate diets have been shown to change bacterial populations (to non-favourable bacteria) in the hindgut. These bacteria produce lactic acid through fermentation, damaging the GIT lining and contributing to a cascade of events that can result in laminitis. In theory, as long as the horse is kept on this antibiotic, rapid shifts in gut microflora which may precede laminitis are less likely to occur. Therefore helping to ‘prevent’ it.

There are a few issues with this. The constant use of antibiotics actually impairs the integrity of the gut lining through several mechanisms. One of the many supportive roles of ‘healthy’ bacteria are to protect and promote a healthy GIT lining. Part of this mechanism involves reducing intestinal inflammation.

Secondly, when a horse comes off the ‘supplement’ (medication) unless strategic dietary practices are implemented, the microflora balance will more likely default to an unhealthy one as a consequence of the use of antibiotics…thereby actually further increasing their risk of future episodes of laminitis than before they were on the supplement in the first place. Keep in mind too that antibiotics also degrade the protective barrier function of the intestinal lining. 

Then we’ve got the nutritional consequences as a result in shifts in GIT microflora. Horses on antibiotics are now lacking the beneficial bacteria to help them properly digest and utilise fibre as an energy source, in addition to the myriad of roles those healthy bacteria play in overall health and performance as outlined previously.

Virginiamycin has been completely banned for animal use in the UK since 2014. This alone should ring alarm bells! The antibiotic was banned as it posed a risk to increased development of antimicrobial resistance. The Veterinary Medicines Directorate (VMD) also found no robust evidence that Founderguard prevents laminitis. They supported that this condition can be managed though animal husbandry and pasture management. They declared the use of Founderguard in horses no longer justified. Globally, we need to recognise the very real problem of antimicrobial resistance and responsible prescribing of antimicrobials in the veterinary profession. As the pathology which drives laminitis is not caused by bacterial infection, we must ask ourselves is the use of antibiotics in this instance responsible? 

We have the opportunity to support healthy GIT microflora, promote healthy GIT integrity and feed our horses so they are able to perform at their best and be in the best of overall health and help prevent laminitis. This is largely dependent not only what we feed our horses, but how we feed them too. It also involves looking at the way we use routine medications in our horses and incorporating alternative strategies to minimise unnecessary use and addressing the side effects they cause when they are required…

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

Spooking, shying and anxiety in horses and ponies are some of the most common challenges we face from a behavioural aspect. When we have a horse or pony which is on edge, spooks at imaginary monsters and feels like they are a bomb under us just waiting to explode, we know something must be done. One of the easiest things for us to manipulate is their feed. We try eliminating things from their diet- often with mixed success. Maybe it helped? Maybe it didn’t. But because our horse possibly seemed quieter or less spooky, we’re not going to add back what we’ve already taken out. Surely they’re better off with less feed anyway and there can’t be any harm in reducing what we are giving them? We also tend to add a myriad of supplements- typically ‘calming’ ones. It’s easy to get to the point where we’re too scared to stop giving any of the supplements we’ve added in case it makes the problem worse. We can get to the stage where we are feeding very little actual feed and so many additives. Sadly, often our horse is no better off in terms of behaviour, and nutritionally is often left with deficits of important nutrients. Furthermore, we can be lacking a solid plan of action going forward in terms of properly feeding and nourishing our horse and addressing the cause of their behaviour.

We need to remember that anxious, spooking or edgy behaviour can be caused by many different things, not just feed. It’s important to consider the potential role of pain, social dynamics, poor fitting tack, the amount of work/exercise we are doing with our horses, their education, learned behaviour, environment and routine. As horsepeople, we also need to take the (challenging) step back and honestly ask ourselves what expectations we have of our horse, and what emotional state and frame of mind are we in? With the fast pace of life many of us lead, it is easy for us to be tense, uptight or in a rush, even when doing the things we love. Our horses instinctively sense this and it can influence the way they behave. The question needs to be posed if what we are asking our horse or pony to do is both clear and appropriate for their stage of development.

But if we focus back to the role of diet in anxious, spooking and edgy horses, one of the most common dietary problems which influence this behaviour is restricting/minimising protein intake, and in particular the amino acid lysine. It’s easy to think that eliminating protein rich feeds can only help a problem and not make it worse. Protein and protein rich foods are commonly blamed for fizzy and bad behaviour in our horses. Yet there is very little worthy evidence to substantiate this and good research to support the contrary.

Protein is made up of small molecules called amino acids. Amino acids and proteins are the building blocks of life. There are 21 amino acids required for a horse to make all the proteins it needs to function, grow and be in good health. Nine of these amino acids are deemed ‘essential’, that is they must be obtained through the diet. In a healthy horse, the remaining 21 amino acids can be produced by the body, even if they are not obtained directly through the food a horse eats. To read more about the role of protein in our horses’ diets, see the article The Importance of Protein.

One crucial essential amino acid in our horses’ and ponies’ diets is lysine. Different foods are comprised of different amino acids. It is important to remember that not all protein sources contain adequate balances of essential amino acids which our horses need for good health. The richest dietary source of lysine for horses and ponies is cooked soybean products. (To read more about soy in the equine diet, visit Soy: The Good, Bad and Confusing! Hay, grass and forages, grains, and beet pulp are all low in lysine. It’s easy for our horses’ diets to become low in lysine. Especially as soon as we start putting them on restrictive diets.

So how can a restrictive diet, low in lysine affect our horses’ behaviour? Through multiple mechanisms! Studies have shown lysine to reduce stress-induced anxiety and to reduce levels of the stress hormone cortisol. Lysine is also needed to facilitate proper calcium absorption. Calcium plays a key role in the function and release of neurotransmitters (natural chemical messengers which influence mood, temperament, learning and behaviour). Insufficient lysine in the diet can interfere with proper neurotransmitter signalling, which can be exhibited as anxiety. Lysine also plays a key role in normal serotonin production and function. Serotonin is a mood-stabilising neurotransmitter and helps our horses to feel calm, happy and relaxed.

It’s important to remember that we don’t always see an immediate or direct correlation between removal or addition of a nutrient in the diet and behavioural changes. It can take some time for effects to be noticed. In the case of lysine, it’s a nutrient which plays many key roles in the body and insufficient amounts affect many body systems. It plays a crucial role in immune function and collagen structure (needed for healthy muscles, bones, tendons, ligaments, skin and hooves). The longer a horse has a low lysine diet, the more the effects compound systemically. 

Our horses’ and ponies’ diets can have profound influences on their overall health, performance, ability to recover, mood and behaviour. It can be tempting to look for a quick fix to our horses’ behavioural issues, yet it is easy to unknowingly compromise their long-term health when doing this. Correctly identifying the contributing cause(s) of fizzy behaviour and addressing them in the most appropriate way(s) is essential to ensure we are doing the best for our equines. Getting professional help to identify potential dietary causes of poor behaviour in horses can pay dividends not only in terms of behaviour, but also in terms of their long-term health and performance.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

What is Protein?

Protein is a crucial macronutrient in a horse’s diet and is comprised of long chains of building blocks called amino acids. There are 21 amino acids. The specific order and combination of amino acids determines the structure and function of each protein. Insufficient dietary intake of specific amino acids limits the production of key proteins essential in our horse’s bodies. For more in-depth information on protein quality see the article: Soy: The Good, Bad and Confusing.

Protein is Needed for Growth, Maintenance and Repair of Tissue

We commonly only think of this as important when we are trying to increase muscle mass in a horse. For instance, building top-line on our ridden horse, or conditioning a thoroughbred yearling for sale. Yet protein is absolutely essential for normal growth and development of the young horse, and recovery from riding and training in active horses. Insufficient protein in the diet can therefore increase risk of illness and injury in our horses. Times of illness and injury also increase protein requirements in order to help recover from the illness or heal from the injury. Providing insufficient protein to a sick or injured horse during their recovery can significantly delay and/or impair their healing and adversely impact their future athletic potential.

Protein Facilitates Biochemical Reactions

Enzymes are a specific type of protein that aid in the normal biochemical reactions that take place in a horse. Specific enzymes are needed to facilitate proper digestion (therefore helping to promote optimal gut health and utilisation of feed); energy production (helping a horse to perform); normal metabolism (helping to regulate weight and temperature in a horse); blood clotting; and muscle contraction. Insufficient protein in the diet can lead to digestive problems- a critical consideration given the heightened focus on gastrointestinal (GI) health. A common mistake is to restrict protein intake in the overweight horse: this can further slow metabolism (compounding the problem) and compromise overall health.

Protein is Required for Proper Communication in the Body

Hormones are chemical messengers that aid in communication between a horse’s cells, tissues and organs. They are needed for everything from normal growth, metabolism, reproductive function and digestion. Amino acids are also an important component of neurotransmitters: the chemical messengers which play a crucial role in a horse’s mood, temperament, learning and behaviour.

Protein Provides Structure

Different types of protein are essential for the formation of healthy bones, tendons, ligaments, muscles, skin and hooves. Depending on the type of protein, they aid in providing structure, strength, elasticity and rigidity to specific tissues. Insufficient protein in the diet can make a horse more susceptible to injury to muscles, tendons, bones and ligaments. They may also have poor skin and/or hoof quality.

Protein Helps to Maintain pH Balance in the Body

Proteins act as a buffer system, helping a horse’s body to maintain proper pH values of the blood and other bodily fluids.

Protein Helps to Balance Body Fluid Levels

Albumin and globulin are two important proteins found in a horse’s blood. They help to maintain the body’s fluid balance by attracting and retaining water. If a horse’s diet has consistently has low quantities of quality protein, the levels of albumin and globulin eventually decrease. This can result in swelling or oedema as these proteins can no longer keep blood in the blood vessels, forcing the fluid into the spaces between cells. The irony is that protein is often blamed for causing swelling in horses- with the reverse often being the cause!

Protein is Needed for a Healthy Immune System

Protein is absolutely essential for white blood cell production and the formation of immunoglobulins (antibodies) needed to fight infection in our horses. Insufficient protein in the diet can leave a horse more susceptible to bacterial, viral and fungal infections.

Protein Aids in the Transportation and Storage of Nutrients

Transport proteins carry substances in our horse’s blood streams- into, out of and within cells. The substances transported by these proteins include nutrients such as vitamins and minerals, blood sugar, cholesterol and oxygen. Whilst we often think of iron as being a key driver in helping oxygen delivery to the body’s tissues, protein plays a paramount role- yet is often overlooked. Specific proteins also have a storage role: ferritin is a storage protein that stores iron.

Problems with Excessive Protein: Myths or Facts?

So now we can see that protein is absolutely vital in keeping our horses healthy, yet is there a downside to this nutrient? And can we feed too much? Like most things, the answer is relative to the situation and the individual horse.

Excess Protein

To overly simplify, horses are unable to store excess protein that they consume in their diet for later use. The metabolism of excess protein increases levels of nitrogen end-products, such as ammonia and urea. A diet containing excess protein will increase the horse’s water requirements and urine output as the ammonia and urea are flushed out of the body. If a horse is kept out at pasture, is only in light work and has free access to plenty of fresh water, this generally isn’t a problem. It is an issue however where horses are stabled. Exposure to this strong urine can cause lung irritation and other respiratory problems. Extra urination means extra wet bedding, which equates to more mucking out.

Metabolism of Protein Produces Heat

Protein digestion and metabolism is a heat generating process. A horse that is on a high protein diet that is burning a lot of protein as an energy source will sweat more to help get rid of the heat. It is important to remember that the body has a preference for using carbohydrates and fats over protein as an energy source, and will only use protein as a significant energy source when these other two nutrients don’t meet their requirements. Protein fed in appropriate amounts to meet a horse’s needs will not contribute greatly to heat production or sweating. Feeding excessive amounts of protein however, particularly to horses in hot and humid climates, or those undertaking moderate to heavy work, can contribute to dehydration and heat stress.

Protein Causes Poor Behaviour/ Hot Horses: MYTH

Protein is often blamed for making horses ‘hot’, nervy or spooky. This is turn can cause some owners to avoid including quality sources of protein in their horse’s diet. Protein has not been shown to cause behavioural issues in horses. Diets which are high in energy and excessive to a horse’s energy needs which are also high in protein can contribute to a horse being hyperactive or silly. The problem here is the overall energy intake, not the protein!

Kidney and/or Liver Damage: MYTH

In healthy horses, high protein diets have not been demonstrated to cause kidney and/or liver damage. In horses that have pre-existing liver or kidney problems, then protein intake may need to be restricted- ensuring that intake is still sufficient to meet a horse’s daily requirements but does not exceed them.

Take Home Message

As a general rule, I see far more horses in clinical practice with insufficient protein intakes compared to those with excessive protein intakes. Insufficient protein in the diet may leave a horse more susceptible to illness and/or injury and delay or impair their recovery. Including adequate, quality protein in the diets of our horses is absolutely essential in order for them to be healthy, perform and recover at their best.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

As a prey species that graze open plains: horses evolved to be slow to show discomfort. Being hard-wired not to show pain is a survival mechanism to protect their livelihood. This is especially true in situations where they feel threatened, as this significantly risks their survival.

Almost any physical discomfort in the horse can result in behavioural changes. Commonly these include things such as kicking, stomping, pawing, biting, teeth grinding, head-tossing, or self-mutilation at work or rest. These can be confusing for us as people to experience or observe, as often the horse doesn’t appear to be in discomfort.

So how do you know if the behaviour is because of pain?

Undertaking a thorough physical assessment of the horse, reviewing dietary intake, medication use, management practices and farriery practices are all sound places to start. For the horse who exhibits such behaviours only when riding, saddle and bit fit should also be assessed.

A useful strategy is to video the horse without anyone present (ie set up a camera in the stable/stall, yard or paddock) to see if it’s doing more conspicuous discomfort behaviours.

Poor behaviour rarely occurs without reason. Identifying and addressing the drivers of poor behaviour is important for the welfare of our horses, and the safety and enjoyment around equines.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

It is well understood that performance and racehorses are subject to significant amounts of stress. This stress in and of itself can result in sub-optimal or poor performance in our horses. Performance aside, prolonged stress has a myriad of flow on effects to the overall health of our horses: it can compromise the wellbeing and function of the gastrointestinal system, the immune system, and the production and function of neurotransmitters (the brain chemicals influencing temperament and behaviour).

What is easily forgotten is that stress affecting our horse’s performance and well being does not necessarily have to originate from sources associated with training or the competitive event. Read that sentence again.

Performance and racehorses are exposed to a range of stressors most of which relate to the way they are kept, fed and managed (this is largely dictated by training regimes, available facilities or convenience). These are stressful because they affect the behavioural needs of the horse as a species.

Behavioural needs are species-specific highly motivated behaviours that are performed by an animal and more often than not have a functional role. The horse has some physiological ‘need’ to perform the behaviour. Foraging (grazing) is a primary example of this. In a natural environment, forage is generally available ad lib with a horse spending up to 70% of its day eating! For horses, the reduction of eating time to two meals per day can meet the nutritional requirements of the animal, but is unlikely to meet the horse’s behavioural need to forage. In the competition horse, restriction of behavioural needs induces a chronic stress response which will subsequently prevent optimal individual performance. It also has a significant flow on effect to gastrointestinal (gut) and immune health.

Some of the most basic feeding and management practices have the most profound influence on our horse’s health and performance. It can be easy to rush in and add the latest fad supplement to our horse’s feed to try and remedy a stressed horse or poorly performing horse, but it is more valuable to ask ourselves:

• What are some of the less obvious sources of stress in our horses?
• What are some of the dietary and management changes we can make for true lasting benefit?

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

For the purpose of this article, we will focus on soy bean meal and feeds containing processed soy- not soy oil or soy bean hulls- as these components alone have significantly different nutritional value and properties.

Pros

Soy is one of the more widely fed significant sources of protein in a horse’s diet. It is a common misconception that protein is only needed to promote weight gain, muscle condition or the development of topline. Whilst it is important in these instances (in combination with appropriate exercise and training), protein is absolutely essential for a multitude of functions in all horses at any life stage and exercise level: it is a critical component of normal immune function; facilitates proper growth and repair of the musculoskeletal system; and is needed for the majority of metabolic processes in the horse. Even horse’s who aren’t in heavy work and/or actually need to lose weight need sufficient protein in their diet.

Protein is comprised of smaller units called amino acids. Horses require 21 amino acids, 12 of which a horse can synthesise (produce) themselves. The remaining nine (and in the case of illness or injury- potentially ten) amino acids must be present in a horse’s diet. These are known as ‘essential amino acids’. In addition to all essential amino acids being present in the diet, they must be present in appropriate quantities- so a horse has enough of each of them to facilitate various bodily functions. If they fall short of any essential amino acids then health, normal development, performance and recovery may be compromised.

With the exception of oils, practically all horse feeds, grains and forages contain SOME protein- Depending on the exact feed source, the actual amounts of protein contained in these feeds will vary. Different sources of protein are comprised of different sequences of amino acids. This influences how useful they are to a horse. Some high protein feed sources are actually of little value to a horse, as they lack decent amounts of essential amino acids that a horse needs, or they are unable to be properly digested and absorbed by a horse.

So how does all this relate to soy? Soy is one of the best dietary sources of lysine for our horses and ponies. Lysine is a very important essential amino acid in the equine and it is generally one which is lowest in our horse’s diets. Lysine is absolutely essential for normal muscle growth and turnover, helps to promote collagen integrity (important for healthy bones, skin, muscles, tendons and ligaments), is critical for proper immune function, and may further help bone health through improving calcium absorption and utilisation. Animal studies have also shown that diets low in lysine may be associated with anxiety. Thus, a diet low in lysine may be one of many potential contributing factors in some cases of horses with an anxious tendency.

For horses competing in endurance events, optimising hydration pre-event is an important consideration. Commercial soy feed products which require soaking before being fed, can help to increase fluid intake in horses. It’s important to keep in mind that there are other feeds which can be used for this same purpose. Soy is not the only option.

Being a low starch and protein rich feed, processed soy meal can aid in stabilising blood glucose levels- thus helping to prevent rapid spikes in insulin levels. High insulin levels are a driving factor of equine metabolic syndrome and are commonly implicated in many cases of laminitis. Horses with Pituitary Pars Intermedia Dysfunction (PPID) (also commonly referred to as ‘Cushings’) and Polysaccharide Storage Myopathy (PSSM)- a component in many cases of ‘tying up’, may also particularly benefit from a diet low in starch and containing adequate quantities of quality protein.

The phytoestrogen content of soy is an important, yet often misunderstood concept. Soy is unique in that it contains a high concentration of isoflavones, a type of plant oestrogen (phytoestrogen) that is similar in function to the hormone oestrogen but with much weaker effects. Soy isoflavones can bind to oestrogen receptors in the body and can either increase or decrease oestrogen levels in the body. Research has demonstrated that when oestrogen levels in the body are naturally low, then ingestion of phytoestrogens may help to increase the body’s levels.  When oestrogen levels in the body are naturally high, then consuming phytoestrogens may help to reduce oestrogen levels, as they bind to some of the receptor sites that naturally produced oestrogen may bind to.

Potential Cons

The phytoestrogen activity of soy may also potentially be a drawback of this feed. Excessively high intakes of phytoestrogens have the potential to decrease testosterone levels, an important consideration in stallions and colts. Soy certainly isn’t the only source of phytoestrogens commonly found in horse diets: clover grass is rich in phytoestrogens. Before attributing potential positive or negative effects of phytoestrogens in a horse’s diet, the total quantity of all phytoestrogen rich food sources needs to be taken into account.

Soy is commonly attributed to causing allergic symptoms in horses- everything from itchiness and skin irritation, colic and digestive disturbances, to overly-reactive behaviour and respiratory issues. Whilst soy is a common allergen in humans, the same has not yet been demonstrated in horses. Diagnostic tests for equine food allergies are difficult to carry out, time-consuming and often unreliable. In clinical practice, I find that the majority of horses with allergy related symptoms (whether these be environmental or food related) improve significantly when overall nutritional status and specific components of both immune and gut health have been therapeutically addressed. Generally something which may appear to cause allergic symptoms in a horse is not the real culprit.

A significant valid concern with soy is the fact that it is one of the most commonly genetically modified (GM) crops. Whilst this is only an issue in some parts of the world, it is certainly worth taking into consideration. Animal studies with GM foods indicate that they may cause some common toxic effects such as hepatic, pancreatic, renal, or reproductive effects and may alter blood parameters and immune function.

Soy is high in omega six fatty acids. Whilst these types of fatty acids are an essential component in our horse’s diets, they are generally present in higher than desirable amounts. Of further importance is the percentage of omega six fatty acids in proportion to omega three fatty acids. High levels of omega six fatty acids with accompanying low levels of omega three fatty acids are known to promote inflammation. Adding large amounts of soy products to a diet already high in omega six fatty acids further accentuates the shift towards a pro-inflammatory tendency. This can  have wide-ranging effects from impairing recovery from training, competition and exercise; compromising immune function; and exacerbating already existing inflammatory conditions such as osteoarthritis, desmitis, placentitis and laminitis to name a few.

Uncooked or even inadequately cooked soybean meal has some anti-nutritional factors. Trypsin inhibitor is the most significant one. Trypsin is an essential enzyme which helps horses to properly digest protein, allowing for absorption and metabolism of the amino acids which make up the protein. Trypsin inhibitor found in uncooked soybean prevents trypsin from being able to properly break down proteins. This means that in the presence of trypsin inhibitors a large percentage of all protein from all sources a horse is consuming is unable to be properly digested, absorbed and metabolised.

Some concerns exist that soy can have a negative effect on thyroid function and can alter the levels of thyroid hormones. Whilst the majority of data is from human studies, it is unlikely that regular consumption of small amounts of soy containing foods have significant impact on thyroid function in healthy subjects. In cases where hypothyroidism already exists (keeping in mind that diagnosis and true cases of hypothyroidism in horses is rare), then reviewing the appropriate feeding of soybean containing products is warranted.

Conclusion

Processed soybean meal and feeds containing this product can be a valuable inclusion in the diets of many horses. Factors which may caution against the feeding of soy to some horses include specific health concerns and where in the world the soy is grown and produced. Soybean meal MUST be properly heat treated to prevent trypsin inhibitor from interfering with protein digestion. The quantity of soy products fed and the overall diet of the horse are crucial factors to take into consideration.

Rarely is anything inherently good or bad: the same may be said of soybean products. The most important consideration is that one size doesn’t fit all: feed the individual horse in front of you!

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

Equine gastric ulcer syndrome (EGUS) affects 60-90% of adult horses and 25-50% of foals and weanlings. The condition collectively refers to sores or erosions that develop in portions of the horse’s sensitive stomach lining. EGUS is largely a man-made disease: common feeding practices; lack of forage in the diet; stress we place on our horses; intense exercise; travelling; and the use of non-steroidal anti-inflammatory drugs (for example ‘bute’ and flunix), corticosteroids and/or antibiotics are some of the many factors which increase a horse’s risk of developing EGUS.

Ulcers can also occur in the hindgut (colon), however, treatment approaches tend to differ to that from EGUS and for the purpose of this article, we will focus on EGUS.

The function and health of a horse’s stomach significantly influences that of the rest of its digestive system- often referred to as the gastrointestinal tract (GIT).

Ulcer medications are sold under many different trade names, but generally contain one of two main drugs. The gold standard pharmaceutical for treating gastric ulcers is the drug called Omeprazole. This medication belongs to a class of drugs called proton pump inhibitors (PPIs). Omeprazole is available in both oral and injectable forms. The other less commonly used medication is Ranitidine. Ranitidine belongs to a class of drugs known as Histamine (H2) Receptor Antagonists.

Although slightly different in their mechanisms of action, both omeprazole and ranitidine result in the prevention/significant reduction of hydrochloric acid production (HCl). This however, is where the problem begins. Hydrochloric acid is an essential and normal component of a horse’s digestive system. It also plays a key role in immune function. 

Hydrochloric acid acts as a barrier against foreign microorganisms and helps prevent infection.

Hydrochloric acid is a key component to help horses breakdown, digest, absorb and utilise their feed, and hence many of the nutrients contained within it.

When HCl production is suppressed, the proper absorption of many key minerals such as calcium, magnesium and iron is inhibited. This in turn can have significant consequences in terms of bone/skeletal health, immune health, energy production, fertility, etc.

The pH of a horse’s digestive tract naturally varies depending on the region of the GIT. The production of HCl is key in controlling the pH in the horse’s stomach. Altering the pH in the stomach subsequently alters pH throughout the rest of the digestive tract. Changes in these normal/natural pH levels for horses influences the community of microbes (bacteria, protozoa, archaea and fungi) that inhabit a horse’s digestive system. Like humans, there are microbes which are beneficial and healthy for horses, and there are also those that are not. When we start interfering with the natural pH of a horse’s digestive tract by shutting down HCl production, we start to create an uninhabitable environment for these beneficial microbes. The result? Commonly an overgrowth of undesirable bacteria, fungi and protozoa. 

The consequences of these changes extend beyond the digestive system. Fine balances in these microbes have significant impacts upon a horse’s overall health, metabolism, ability to digest, absorb and utilise their food and immune function.

In terms of immune function, shutting down HCl production is a double whammy: the horse loses its first line of immune defence from the direct action of HCl in the stomach (helping to counter ingested pathogens), in addition to the changes in microflora further down the digestive tract. Research suggests that approximately 70% of immune function is attributed to the role of specific cells of the GIT and the microbes which inhabit it. Thus adverse changes in the microbial population and balance can result in significantly impaired immune function.

Healthy bacteria further down the GIT are also vital to synthesise B group vitamins (including biotin). Hence it is no coincidence that horses with compromised gut health often have poor hoof quality. B group vitamins play vital roles systemically in our equines: they are required for energy production and proper metabolic function; reproductive function and neurotransmitter production and function (natural chemical substances produced in our horse’s bodies).

In terms of neurotransmitter production and function, again ulcer medications can have a wide ranging effect. Undesirable changes in microbes throughout the digestive tract directly influence the production and function of neurotransmitters (chemicals which influence temperament, behaviour, motor control, pain perception and learning in horses). It is thought that 60-95% of neurotransmitters are produced by microbes of the GIT. This may in part explain why you can still have a cranky, irritable, spooky horse despite extensive treatment for ulcers. Neurotransmitters also play a key role in influencing sensitivity and motility of the GIT. Ever had a horse prone to colic that is routinely on ulcer medication?

Unfavourable changes in GIT microflora are also known to heighten systemic inflammation in the body. Thus any inflammatory condition (including: sesamoiditis; arthritis; inflammatory bowel disease, placentitis, desmitis, laminitis) are potentially exacerbated by adverse changes in GIT microflora.

When it comes to fertility and reproductive function, the use of omeprazole needs to be considered. In stallions, omeprazole use may result in impaired sperm quality, abnormal sperm morphology, reduced sperm motility and reduced sperm count. Omeprazole may also cause a reduction in serum testosterone levels. In mares, particularly those with chronic recurrent infections and biofilms-their ability to colonise their reproductive tract with beneficial microflora may be hampered by the use of ulcer medications.

The effective prevention of gastric ulcers requires an holistic approach that focuses on dietary and management strategies. Through diligent management and qualified prescription, ulcers can be treated effectively with a combination of nutraceuticals and specific herbal medicines. These should always be prescribed in conjunction with appropriate dietary modification. Use of any medication needs to be judicious- as medications rarely come without side effects. Not only is repeated and/or extensive use of PPIs or H2 receptor antagonists financially expensive, their long-term effects on a horse’s health can be extremely costly.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

There are many physiological changes thought to go hand-in hand with wind sucking and crib biting. Changes in the microflora of the gastrointestinal tract (GIT) and acidity of the hindgut are believed to be associated with the condition- with a bidirectional relationship likely (ie poor gut microflora adversely influencing neurotransmitter production and function and inflammation, and changes in neurotransmitters and inflammatory mediators associated with altered gut flora driving the windsucking/cribbing).

Again a low fibre/forage diet plays an important component in adversely affecting gut microflora and acidity of the digestive tract. The use of certain medications such as antibiotics, NSAIDs (ie. bute and flunix) and ulcer medications also alter gut microflora. Low blood levels of specific antioxidants have also been demonstrated in horses which windsuck or crib.

The super-interesting part of these behaviours are the way they alter receptors in the brain. The act of windsucking or crib biting activates narcotic and dopamine receptors (‘feel good’ receptors) in the central nervous system, thereby rewarding the behaviour. Thus, the more a horse windsucks or cribs, the more their brain feels rewarded- similar to human drug and alcohol addictions. When we understand this, we can understand why wind sucking collars are ineffective in many cases.

Wind sucking and cribbing may be ‘simple behaviours’ but their causes and effects are complex!

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

The Oestrus Cycle in the Mare

Horses are seasonal breeders: that is, they are programmed to mate and become pregnant at certain times of the year. Over the winter months, the majority of mares (particularly those in temperate climates) are anoestrus- meaning they don’t cycle. As daylight hours increase over the spring and leading into the summer, hormonal changes occur in the body, acting as a stimulus for them to become reproductively active. Nutrition and climate also play an important role in influencing a mare’s oestrus cycle. Some mares appear to cycle all-year round (this is more likely in far-north Australia).

Early in spring, as a mare transitions from aneostrus to cycling, the timing of when she comes into heat may be prolonged or erratic, with accompanying unpredictable behaviour. As the season progresses, the mare’s cycle should become more regular: having three week cycles. The average oestrus cycle of a mare is 21 days, which can be divided into two distinct phases: the oestrous phase (when a mare is ‘in heat’ and receptive to a stallion; and the dioestrous phase (when a mare is generally not receptive to a stallion). The oestrous phase usually lasts somewhere between 5-7days. At this time, the hormone oestrogen is at a high level, and this is the period often associated with changes in behaviour in susceptible mares. The dioestrous phase is generally lasts for 14-16 days, characterised by high levels of the hormone progesterone and a mare generally having little or no receptivity to a stallion.

It is these two female sex hormones- oestrogen and progesterone which strongly influence behaviour patterns demonstrated by many mares and fillies during the breeding season. Most commonly, a mare who is susceptible to displaying ‘mareish’ behaviour will demonstrate this behaviour during the oestrous phase, in associating with elevated oestrogen levels. It is important to remember though that there are always exceptions to this- especially in mare’s/fillies who have erratic cycles.

Important Considerations

Before concluding that a mare or filly’s behaviour patterns are purely related to her oestrus cycle, it is important to ensure that there are no significant other contributing factors. As in all animals, horse behaviour is comprised of several components, including: innate (genetic); learned (environmental); pain-associated behaviour; and sexual (hormonal). Keeping this in mind, it is important to remember that some behavioural problems are the results of genetics, injury/illness, poor training and/or past bad experiences.

Additionally, some diseases can result in behaviour that appears very similar to what many mares experience during the breeding cycle. An ovarian tumour can cause consistently high levels of oestrogen, which may cause the mare to be constantly ‘in season’. Bladder infections can cause a mare to raise her tail and urinate frequently; and injury, nerve impingement or arthritis in the spine or hind legs can result in a mare frequently squatting down. These are all signs that may be typical of a mare in season, with only subtle differences. For these reasons, ongoing behavioural issues should be thoroughly investigated by a vet to rule out illness or injury.

Natural strategies and treatments to managing behaviour in the oestrous cycle

For the healthy mare whose signs are purely related to hormonal changes (having excluded other conditions/reasons mentioned above), there are many useful dietary, nutritional and herbal strategies which can be employed.

It is of upmost importance to remind owners/riders of mares and fillies that many of these horses who experience sensitivity to physical touch during their cycle are actually experiencing some degree of pain or cramping, similar to many human women! Hence some care and compassion are called for, and appropriately addressing and rectifying this through the use of nutritional and herbal strategies is invaluable.

Dietary and  management strategies aim at reducing excessive oestrogen levels during the oestrous period- thereby helping to reduce classic signs associated with the dominance of this hormone. Keeping a mare at a healthy weight and avoiding becoming overly fat is one of the first considerations. Fat tissue itself acts as an endocrine organ (meaning it produces hormones), and commonly results in the production of high oestrogen levels and inflammatory mediators, thereby aggravating behavioural symptoms, in addition to cramping and pain. Another important dietary consideration is keeping the mare/filly on a nutritional program which stabilises blood-glucose levels, thereby keeping the levels of insulin (another hormone) balanced. Generally, a diet which is high in roughage and low in refined grains, starches and added sugars can help to meet all of the above goals. Ensuring the diet has sufficiently high omega-3 fatty acids and proportionally lower levels of omega-6 fatty acids is important. For the horse with high energy requirements, additional sources of healthy fats may be used to meet these needs. The importance of balancing feed intake with appropriate exercise cannot be over-stated: physical activity plays an important part in weight management; regulating blood glucose and insulin levels; and keeping inflammatory mediators at healthy levels. Cooked and/or crushed linseed is a beautiful addition to the diet: helping to balance inflammatory mediator levels; providing a rich source of dietary lignans (which can help to reduce excessive oestrogen levels); and helping to promote a healthy coat and skin (thanks to the high oil content).

Nutritional supplements can be a most valuable addition on several fronts when aiming to promote health and happiness in the hormonal mare! Strategic use of appropriate nutrients can help to reduce inflammation; minimise spasm and cramping; and optimise blood glucose and insulin levels. Depending on the individual horse, these can include: high quality fish oils; magnesium; B group vitamins; vitamin C and chromium. As with any nutritional supplementation, professional consultation should be sought to ensure safety and efficacy.

Herbal medicines are a most effective form of treatment in holistically managing a hormonal mare. When prescribed appropriately, herbs such as Vitex and White Peony can help to regulate a mare’s cycle, aiding in  ‘normalising’ behaviour, balancing oestrogen and progesterone levels and reducing spasmodic cramping and associated sensitivity to touch (think of the mare who hates her flanks being touched or leg pressure applied when in season). Additionally, the herbs Ginger, Sarsaparilla  and Cramp Bark are incredibly effective at modulating inflammation, cramping and associated pain when in season. For the mare who still remains somewhat edgy and irritated, Chamomile, Vervain and Valerian can be incredibly useful. As with any herbal prescription, seek professional, qualified advice to ensure the safety, efficacy and appropriate use of such herbs. In particular, the use of hormone modulating herbs (such as several of those mentioned above) need to be strictly monitored. Several of the herbs previously mentioned also have restricted use in some forms of competition.

Mares and fillies can be some of the toughest and most competitive horses. A little understanding of the oestrus cycle, how to best manage it, and effective strategies for those horses that become ‘out of sorts’ during this time can go a long way to achieving the results you are after, not to mention having a happier, more co-operative horse!

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

The quality of these supplements and ingredients contained within them vary greatly. Many contain nutritional and/or herbal constituents such as: magnesium, tryptophan, B group vitamins, chamomile and valerian.

But do these actually work?….

Supplementation is only advisable where there is an understanding of how they will help achieve specific therapeutic treatment aims. They should not be used to replace poor management practices. Before using a calming supplement, the following needs to be asked and addressed: does the horse have good gastric health; is the horse being exercised frequently; is the horse in pain; does the saddle fit correctly; do the horse and rider capabilities match; is the rider relaxed when riding? Without addressing primary root causes, truly effective results will never be obtained by any supplement. Any benefit derived from the supplement will be a poor ‘band-aid’ fix.

For a supplement to be truly effective, it needs to be given in sufficient quantities (often, to achieve a therapeutic effect, the actual amount of the supplement required by the horse is much greater than the dose suggested on the label.) It also needs to be given in a form which the horse can readily digest, absorb and metabolise. It needs to contain sufficient ‘active constituents’ (the actual parts of the supplement which exert a biological effect). Many commonly available products, (especially those with herbal ingredients), actually have minute amounts of these very important active constituents.

For racehorses and performance horses/ponies competing at a high level, the use of specific herbs are not permitted in competition. Many of these herbs are those commonly used in calming products.

When selecting a supplement, the question needs to be asked ‘why are you adding it?’. Have you adequately identified and addressed all possible reasons as to why you feel your horse needs it?

Supplements should only be added to the diet when you can confidently answer the questions: why you are using them; what specific modes of action they are targeting; and what therapeutic goals will they achieve?

Specifically indicated nutrients and herbs can be extremely valuable to use in some cases of anxious or stressed horses. The correct selection and and application of appropriate herbs and nutrients is key to efficacy: always remembering that they do not replace good feeding, riding and management practices.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

The habit can negatively effect a wide range of horse health parameters, resulting in conditions such as dental disorders (wear of incisors); temporohyoid joint damage; poor performance; weight loss; colic; and diminished learning.

From a holistic perspective, many factors may contribute to the development of wind-sucking. Much emphasis is deservedly placed on diet and management. Research in recent years has highlighted higher levels of oxidative stress in horses which wind-suck.

Continuing along the oxidative stress theory, recent research has demonstrated wind-suckers to have lower serum levels of selenium. Selenium is an essential trace mineral which plays many important biological roles in the equine: one of these being its role as a potent antioxidant.

Whilst selenium must be considered, supplementing selenium without looking at and addressing the horse’s overall health, nutrition and management is not recommended. Selenium is a nutrient which has a low threshold for toxicity, and should only be supplemented judiciously.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

Equine asthma (EA) is a common cause of poor performance in racehorses and performance horses. Yet, the side effects of a drug commonly used to help mange clinical signs in the condition may play a significant role in anxious, worked-up, stressed, irritable behaviour in some horses.

Two commonly used medications in EA are Claire Gel and Airway Gel. The active ingredient in these products is the drug Clenbuterol. Clenbuterol is a beta-2-adrenoceptor agonist. Beta-2 adrenoceptor agonists work by mimicking the effects of epinephrine (adrenaline) in the body.

It is widely known that the use of this drug has been exploited due to its ability to burn fat whilst preserving lean muscle tissue. Sadly, this practice can severely compromise the horse’s health.

Clenbuterol, being highly stimulating, can adversely affect the temperament and behaviour of the horse. It has also been shown to deplete the body’s levels of taurine and potassium- which may lead to cramping (amongst other undesirable side effects). Additionally, animal studies have demonstrated that the drug depletes zinc levels and causes irreversible damage to cardiac tissue.

Negative effects upon stallion fertility have also been postulated. The drug has been shown to permanently damage the Sertoli cells in the testes-these are the cells where sperm is produced.

In the case of preventing and managing airway disease- there are many steps which can be taken to reduce the need for the drug. These include practices during feeding and stable management which reduce airway irritation and inflammation in the horse. The strategic use of several permissible nutritional supplements can help to alleviate airway inflammation, spasm and mucous production.

For a horse not currently in competition, correctly prescribed herbal medicine provides many therapeutics to support immune function, reduce mucous production, thin mucous and treat respiratory tract infection- all which may help to rectify breathing difficulties in the horse..

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

Recent research has highlighted that sufficient vitamin D is essential to optimise intestinal uptake of magnesium. This is a very important consideration, especially for those horses who spend much time stabled, rugged or in climates where UV exposure is low (think of temperate winter climates).

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

From a dietary perspective, it is thought that horses may chew wood when they aren’t consuming enough fibre in their diet. Even horses grazing pasture may need to be fed additional hay to meet their fibre requirements. Adequate fibre in the diet is incredibly important for optimal GIT function, promoting balanced microbial flora of the GIT, preventing ulcers, supporting immune function and supporting neurotransmitter production (just to name a few of its roles!)

Lignophagia may also be due to boredom and left unaddressed, may develop into a stereotypy behaviour. As with any abnormal behaviour it should be viewed in a holistic context.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

Whilst no nutritional supplement will prevent estrus in the mare/filly: signs, symptoms and behaviour may be able to be preferentially modified. Modulating specific hormonal, neurotransmitter and inflammatory pathways and correcting nutritional insufficiencies can have a significant impact. This is a key area where therapeutic nutritional intervention differs distinctly in just meeting a horse’s daily nutrient requirements.

Time and energy can be wasted on being angry/frustrated by the current rulings, or minds can be opened to explore other options, gaining knowledge and tools to use to one’s advantage. 

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.

If a horse you work with is facing behavioural or performance challenges, it is well worth considering what you (or the person working with the horse) is potentially feeling and what influence you/they may be having on the horse.

Although there is certainly room for more research in the area, recent findings also suggest that both the rider’s and horse’s personality affect the level of cooperation between the two: some horses suit some riders.

Optim Equine

Camilla Whishaw is a highly regarded, experienced horsewoman and naturopath, helping to holistically treat and manage a broad range of equine health conditions and injuries, with a passion for mare and stallion fertility.

As a world-renowned practitioner, presenter, author, and consultant in the field of Equine Naturopathy, Camilla shares her knowledge through keynote presentations, interviews, lectures, panel sessions, and workshop training.