Equine Skin Cancers

Skin tumors in horses are not uncommon. While a tissue biopsy is the definitive way to identify the tumor type, location and appearance can offer clues for identification.

Sarcoids

Sarcoids are the most common skin tumor in horses and can be separated into different types depending on appearance.

  • Occult sarcoids are the earliest form of sarcoids and can progress to other forms or remain quiet for years. They vary in size and range from a roundish area of slightly different hair type to a gray hairless circular area. The skin can feel thickened and may resemble a rub from tack or ringworm lesion.
  • Verrucous sarcoids appear gray and scaly or wart-like. They can also become ulcerated and the skin in this area may crack easily.
  • Nodular sarcoids are obvious firm masses which may be attached within the skin or the skin may be separate from the nodules. The axilla (arm pit), eyelid, and inner thigh are common locations for nodular sarcoids.
  • Fibroblastic sarcoids are aggressive and ulcerative in appearance. They can occur anywhere on the horse’s body. The other types of sarcoids can evolve into the fibroblastic type from local trauma and irritation. Fibroblastic sarcoids are further divided into subtypes based on the extent of their attachment to deeper tissue.
  • Mixed sarcoids have characteristics of some or all the types listed above.
  • Malevolent sarcoids are fortunately the rarest form. These sarcoids are highly aggressive and spread extensively throughout the skin, with ulcerative and nodular cords of tumor tissue.

While sarcoids can be locally invasive, they typically do not spread throughout the rest of the body. However, they can be frustrating to treat, become very inflamed, and occur in locations that interfere with tack.

Unlike some of the other types of skin cancers, there does not seem to be a color predisposition to development of sarcoids. The development of sarcoids is the result of an individual horse’s immune system/genetic susceptibility and exposure to the bovine papilloma virus.

The location and type of sarcoid determines the best treatment. Unfortunately, there is not any one treatment approach effective for all sarcoids, and individual sarcoids of the same type may respond differently to the same treatment. Treatment can involve topical chemotherapy or chemotherapy injected into the sarcoid, surgical excision, laser surgical excision, immune therapy, electrochemotherapy, or radiation. Incomplete removal of a sarcoid can lead to recurrence at the same site and a more aggressive sarcoid.

Squamous cell carcinoma

Squamous cell carcinoma (SCC) is the second most common skin cancer in horses. This tumor type develops from skin cells and is seen more commonly on pink skin. Common locations include the eyelids and external genitalia. In addition to horses with pink skin, such as Appaloosas and paints, Belgians and Haflingers may be predisposed to SCC.

Early SCC can appear as a depigmented patch of skin or dry crusting area, progressing to an ulcerated, raised, or cauliflower-like mass. It is best to be proactive about these lesions early, since removal becomes more challenging with increasing size. Always closely monitor areas of pink skin on your horse.

Treatment options for SCC include surgical removal of the mass, local treatment with chemotherapy, CO2 laser treatment, and cryotherapy. Larger and more complex masses, or those involving significant portions of the eye or eyelid might require removal in a hospital setting by a surgeon. At-risk horses benefit from wearing a UV-protective sheet when UV-exposure is high, as well as a UV-protective fly mask. Remember to check your horse’s eyes daily when wearing a fly mask.

Melanomas

Although human melanomas are frequently associated with UV-exposure, melanomas in horses are usually associated with coat color, with up to 80% of gray horses developing melanomas at some point during their lifetime. Melanomas arise from melanocyte cells, which produce the pigment of the skin. Depending on tumor location, melanomas can dramatically impact the horse’s quality of life. At times they may ulcerate and exude a tarry dark substance (melanin).

Common locations of melanomas include the underside of the tail, around the rectum and external genitalia, and around the mouth. Melanomas can also spread to internal organs, such as the liver, spleen, and lungs. Surgical removal of external masses when they are small is recommended, and surgical removal is more effective than medical therapies.

Medical therapies include local injection with chemotherapy, cimetidine (an antihistamine, with mixed results), and a newer option: a melanoma vaccine. A canine melanoma vaccine has already been developed, so similar research is underway for an equine melanoma vaccine. The idea is to create a vaccine unique to that horse to stimulate the immune system to target melanoma cells. While the vaccine does show some promise in reducing tumor size, it unfortunately isn’t a guaranteed cure.

Bottom line: be proactive in monitoring your horse’s skin, and contact your veterinarian if you observe any suspicious skin lesions.

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Saying Goodbye: responsible end-of-life horse stewardship

This is a hard post to write. Euthanasia is very difficult topic, and one that none of us want to think about, but it’s something that we, as horse owners, will all have to deal with at some point. 

Responsible horse stewardship includes making the decision to say goodbye to our equine partners when the time comes. Knowing what to expect, and understanding some of the practicalities of the process, can help us to be prepared to offer our beloved horse companions as pain, and stress-free an exit from this life as we can provide. 

How to make the decision 

“What do you think, Doc?” 

As veterinarians we get asked this question all of the time.  It can pertain to anything from how to deal with a lameness issue, to when it’s “the right time to say goodbye.”  The “when to say goodbye” question is arguably the most difficult we – both as horse owners and as veterinarians – have to face. 

Sometimes it is certainly far more clear cut than others.  Emergencies such a broken leg or a very sick or colicky horse can leave horse owners no choice but to end the suffering. On the other hand, the aging horse which is not holding weight or is limping around on a chronic basis can be a far more difficult and nuanced discussion.

That is the important part though – the discussion. 

It can be a very difficult thing to discuss or even think about, but your veterinarian should be able to guide you through the process so that you and your family can make an educated decision.  Elements such as chronic pain or lameness, weight loss, and inappetence are three common issues which often start the concern that it “might be time.” 

Part of the conversation that I personally have with clients is that often the horse “tells us.”  Their eye may change and become dull. They may start to lack the zest for life which they had years (or even weeks) ago.  They may become disinterested in food, or companionship, or just stand and stare off into the distance as they retreat into themselves. It can be different for different horses, but as the person who knows your horse the best, you will probably recognize it. 

When horses start to have difficulty just being horses, the term “quality of life” comes into play.  Defining that concept can be difficult to pin down, but in the end it is the most important piece of the puzzle. As the stewards for our horses, if the quality of life has significantly changed I believe it is our duty to end their suffering.

 What to Expect

 Your veterinarian should walk you through the practicalities, but generally it is done by your veterinarian with a lethal injection. There is no need to move the horse to a clinic or hospital for the procedure. It can be done where your horse lives, in a familiar and reassuring location. If possible it’s good to conduct the procedure in an area that will be accessible by removal equipment or a backhoe, depending on what you do with the physical remains (we’ll discuss that more below). 

Typically, a sedative is given first via intravenous injection in the neck, to help the horse fall more easily and so the horse doesn’t get distressed as they start to feel sleepy. After this an overdose of an anesthetic type drug is given, stopping the horses’ heart. Sometimes the horse makes involuntary movements, jerking limbs or gasping. Although this can be disconcerting, it is important to remember that the horse is unconscious, and is feeling no pain or distress.

 The drugs take effect very quickly. Your veterinarian will confirm death, and allow you to have some time alone with your horse if you desire.

 How to Deal with Remains

Once a horse has been euthanized with lethal injection, the body is toxic.  It must therefore be dealt with properly. Here in Jefferson County, we have 3 options for the remains: communal burial, plotted burial, and cremation. In all instances an animal removal service is used to transport the body to its final location.  This is often referred to as the “rendering” truck, but nothing does in fact go to the rendering plant.  Communal burial is a mass grave at a non-visitation location. If you feel that you may want to visit a site in the years to follow, there are plotted burial options.  These, and cremation, are significantly more costly, but they are viable options.

Because of their size, there are only a limited number of places which can deal with a horse either for burial or cremation, so planning and discussion of what to do with the remains months or even years before can make the whole process run a little smoother.  Euthanasia discussions are not easy ones to have, but for the sake of our equine companions, they are a necessary one.

EGUS Series Part 3: Management of the horse with Equine Gastric Ulcer Syndrome (EGUS)

So, we now know how to recognize horses afflicted with EGUS and also the proven therapeutic methods used to treat such horses.  This begs the question, how do we manage these ulcer patients?   Numerous studies have shown that intense training and competition schedules, frequent shipping, high concentrate (starch) diets, decreased availability of pasture and insufficient ingestion of hay are all common contributing factors to the development of EGUS.  Our goals as veterinary professionals are multifaceted and include neutralization of acid, promotion of mucosal repair, and the improvement of management processes. 

Photo Courtesy Public Domain Photos via Flickr

Knowing that the equine stomach produces 1.5L of acidic stomach juices on an hourly basis, we can already begin to recognize the benefits of having a constant input of hay into the horse’s GI tract. Additionally, if your horse can handle some alfalfa in his diet, there are several benefits to ingesting this leafy legume.  When compared to timothy, brome and orchard grass, alfalfa is higher in calcium and protein, both of which act as literal chemical buffers to stomach acid.  Additionally, if we consider that alfalfa often has a coarser texture, this means the horse is required to take more chews before swallowing the feed.  As the horse masticates, he produces saliva.  This gooey substance is high in bicarbonate, a chemically basic molecule which also aids in the neutralization of stomach acid.  If your horse is an easy keeper or has some metabolic/nutritional restrictions, high quality straw can also be incorporated into the horse’s forage regime to provide valuable roughage without adding starch or calories.  

Why do we avoid diets high in starch?  As starch is broken down in the stomach, it is fermented by the resident bacteria into volatile fatty acids and lactic acids, all of which contribute to the already acidic environment of the stomach.  If your horse is in an intensive training program and consuming large amounts of grain, breaking the total volume of grain into multiple small feedings throughout the day will help to reduce the amount of acid produced at the time of ingestion.  Additionally, fats can be substituted for starches in the form of rice bran, bean meal, and oils as a means to provide calories without the detrimental by-products of starch fermentation. 

In addition to the continuous ingestion of fiber products, care should also be taken to reduce the stresses of competition and travel.  For those equine athletes where the stresses of competition are unavoidable, the use of PPIs or H2 blockers to prevent the development of gastric ulcers is highly recommended.  Finally, while there is no direct link today between the use of probiotics and the prevention of gastric ulcers, such products may be helpful in maintaining hindgut health in stressed equines. 

Other ulcer-inducing risk factors in an equine life may include aggressive pasture/stall mates, lack of turnout, consistent loud noises, persistent radios, systemic illness, chronic pain, long term use of NSAIDs (bute, banamine, etc), intensive breeding programs and routine training on an empty stomach. 

In conclusion, EGUS is a clinical condition requiring both medical and long term nutritional management.  The continuous ingestion of fiber products is by far one of the most important aspects to managing a horse with clinical signs of ulcers, and in achieving long term optimal GI health.

EGUS Series Part 2: Common (Proven) Treatment Methods of horses with Equine Gastric Ulcer Syndrome (EGUS)

Let’s say you’ve just indulged in a rich gourmet meal complete with red wine and a decadent chocolate dessert.  An hour or so later, you’re regretting that decision as some pesky heartburn keeps you awake.  Eventually you swallow some Tums©, Tagamet©, Zantac© or even Nexium© and breathe a sigh of relief as those clinical signs abate and you drift off to sleep.  Believe it or not, many of the medications we use to treat our own heartburn work on horses as well.  The goal of EGUS therapy is not to treat the ulcer itself, but to decrease the acidity of the horse’s stomach to allow its natural healing mechanisms the opportunity to repair the damaged mucosal lining.

The gold standard in the treatment of EGUS is omeprazole, sold under the trade name Gastroguard©.  This product stops the production of gastric acid at the immediate source, and is known in the chemical world as a proton pump inhibitor (PPIs).  By stopping the production of gastric acid, the mucosal lining of the stomach is allowed to heal, which can take anywhere from a couple days to multiple weeks, depending upon the size, severity and location of the ulcer within the stomach.  UlcerGuard© is another omeprazole product, given at a quarter of the dose of Gastroguard©, and utilized in the prevention of gastric ulcers.  Both of these products are given once a day, and elicit the best response when given in the morning on an empty stomach.  They are most effective in the first eight hours after administration.  It must be noted that long term use of PPIs has been shown to impair the digestion of protein, an integral component to a horse’s nutritional demands.  PPIs are safe for use up to 90 days (so your 4 weeks of omeprazole therapy is perfectly safe) but relying on them for longer periods of time is not recommended. 

Ranitidine (Zantac©) and cimetidine (Tagamet©) have also been used routinely in the prevention and treatment of gastric ulcers.  Both drugs are considered H2 receptor antagonists, or H2 blockers.  Where omeprazole prevents the production of gastric acid directly at the source, H2 blockers are one step removed from that process and prevent the H2 signaling molecule (histamine) from binding to the receptor which activates the production of gastric acid.  Sounds complicated, right?  My goal in providing readers with such information is not to overwhelm you, but instead, to illustrate why veterinarians consistently turn to omeprazole when faced with EGUS; it halts the production of acid at the source and has a longer duration of efficacy compared to H2 blockers.  Sometimes, though, weeks of omeprazole therapy are not a viable, financial option for clients, so we may turn to the H2 blockers to help try to achieve similar results in the reduction of clinical signs of EGUS.  For the best efficacy, H2-blockers must be given three times a day, making them slightly more challenging from a management perspective.

Sucralfate is another product occasionally used as a protective agent in horses with ulcers located in the glandular region of the stomach.  When exposed to such acidic environments, this fluid is converted into a sticky substance which coats the lining of the stomach and binds to preexisting ulcerations to form a protective barrier.  This product must be given on an empty stomach (which we try to avoid in horses with EGUS) and may prevent the uptake of other drugs administered simultaneously.  While effective, the size of the dosage and the duration of therapeutic programs often makes this product cost prohibitive. 

A phenomenon which must be mentioned in this discussion is that of rebound acid hypersecretion.  Long term use of PPIs followed by abrupt discontinuation of therapy has been shown to cause a consistent increase in gastric acid production, often worse than the initial stomach condition.  When using PPIs, it is important to wean the horse off of medication using progressively lower doses over the course of 10 days.  There are several studies demonstrating the beneficial effects of using sea buckthorn in the prevention of rebound acid hypersecretion. 

Stay tuned for Part 3 of Dr. Hartman’s blog regarding the management of horses with EGUS!

EGUS Series Part 1: What’s the fuss over gastric ulcers?

Be it in the show ring or over dinner with horse friends, the topic of gastric ulcers always seems to elicit sentiments of frustration and misunderstanding.  What causes these pesky ulcers and what can we do as horseman to combat them?

To start, it’s important to understand that before horses were domesticated by humans, they spent their days slowly grazing across the plains and grasslands.  The slow ingestion of fibrous plant products creates an integral part of the horse’s digestive mechanism called a fiber mat, which naturally floats on the top of the stomach contents. 

Why is this fiber mat so important?  The horse’s stomach is separated into two regions, glandular and non-glandular.  The glandular region is responsible for the production of gastric acid which is necessary for the digestion of forage.  To avoid self-destruction, the glandular region of the horse’s stomach has protective mechanisms that keep the gastric acid from digesting the very tissue that produces it.  Unfortunately, the non-glandular region does not possess such protection and is susceptible to the destructive effects of the acidic stomach contents.  This is where the fiber mat comes into play.  Horses that graze throughout the course of the day are continuously adding plant fiber to the fiber mat which serves as a protective boundary between the acidic gastric contents and the non-glandular portion of the stomach. 

Let’s jump ahead to our typical domesticated horse which lives in a commercial boarding situation.  These horses are usually fed twice a day, often going more than twelve hours between their evening meal and breakfast.  The detriment here is without the continual ingestion of hay, that fiber mat is quickly digested and sent past the stomach into the rest of the GI tract.  This leaves the non-glandular portion of the stomach exposed and susceptible to the deleterious effects of the acidic stomach juices, as these secretions are produced on a continual basis.  Now, let’s say we decide to ride this horse without his fiber mat and the increased activity level causes more splashing of the stomach contents onto that already sensitive region.  As the acid begins to eat away at the lining of the non-glandular region of the stomach, the horse is thrown into a downward spiraling scenario that, without medical intervention, is quite difficult to recover from. 

How do you know if your horse has ulcers?  Common clinical signs of a horse with ulcers are aversion to tightening of the girth, sensitivity to grooming (especially behind the elbows), finicky eating habits or changes in behavior both on the ground or under saddle.  The only guaranteed diagnostic method to confirm the presence and severity of gastric ulcers is by passing an endoscope into the horse’s stomach and visualizing the integrity of the gastric mucosal lining.  For many of our clients, this is not a viable diagnostic mechanism, so instead, we assess the horse’s response to medical therapy for ulcers.  If there is a vast improvement in clinical signs over the course of therapy, the likelihood of gastric ulceration is high and we can continue with medical intervention and nutritional management. 

Stay tuned next month for part 2 of our blog discussing the treatment and management of horses with Equine Gastric Ulcer Syndrome (EGUS)!

Equine Preventative Medicine Checklist

Along with spring comes vaccinations and preventative care appointments for our equine friends. We all understand the importance of preventative medicine, but it’s easy to miss things, so we’ve prepared a list of what you should be doing with your horse to make sure they’re healthy and prepared for summer riding season.

Vaccinations

We will start with the easiest – vaccinations. Vaccine protocol for the spring varies depending on your geography and your individual horse’s exposure potential and travel schedule. Always consult with your veterinarian if you are going to travel somewhere new with your horse. Here on the Front Range, we typically recommend a 5 way (eastern and western equine encephalitis, tetanus, rhinopneumonitis, and influenza) and a West Nile booster as the basic starting place for spring vaccinations. For a more in depth discussion of the vaccinations we recommended in Colorado and why, see the blog titled Why are the Vaccines we give in Spring So Important Here in Colorado?

Deworming

Deworming used to be easy – give your horse a deworming paste at set intervals and you’re done. But research has shown that deworming is certainly not as straightforward as we once thought it was. There are several options and differing approaches to deworming, and whether you opt to use a classical “rotational” deworming, or a more targeted “Fecal Egg count” approach, spring is a time to think about how to protect your horse from internal parasites. There are pros and cons to different deworming approaches, and we have complete articles on both of these regimes listed below.

Rotational Deworming – What’s the Right Choice?

The Scoop on Fecal Egg Counts

Dentistry

teeth

Although there is nothing tying teeth floating to vaccination, deworming or seasonality, most people (veterinarians included) like the convenience of combining all of the preventative medicine into a single visit. Spring is a critical time to have your horses’ teeth checked comprehensively. Tooth and other mouth issues can have a dramatic impact on your horses’ comfort, performance, and even lameness issues. Dental issues and questions like “Does my horse need a float?” are immense subjects and are covered in detail in previous issues of the blog.

Why is Regular Dentistry so Critical to your Horses’ Health?

How Do I know My Horse Needs a Float?

Why Do I Need to Float my Horses’ Teeth?

Physical Examination

A good general physical exam is a good idea for all horses this time of year so that we (both owner and veterinarian) are assured that there is no need for an alteration to the diet or that some insidious disease process is slowly creeping in unnoticed. It’s also very helpful to have a baseline of your horses’ health so when changes happen they can be noticed, and dealt with, quickly. Summer is riding and show season, and a physical examination will ensure your horse is at the top of their game, making your time together enjoyable for you both. An important aspect of the physical exam that often gets ignored is a very brief (just a few minutes) lameness exam. Whether you have noticed that your horse is tripping a bit more, or he just hasn’t been evaluated, a check of his legs could be invaluable in finding a mild issue before it is a major one. If this is something you are interested in, be sure to let the office know when you schedule your appointment that you would like the veterinarian to spend a bit of time with a lameness evaluation, so that a scheduling issue doesn’t arise.

Spring Preventative Medicine Checklist

Below is a quick reference for when your vet arrives for spring tune ups for the horses. I have had clients use this little outline as a basis for questions they have for the vet when he or she arrives. We all fall victim to “I forgot to ask while you were here” questions! Happy trails and enjoy the beautiful Colorado spring!!

Quick Checklist for Spring:

  • vaccines – 5-way and West Nile Booster
  • deworming or FEC – which is better for your horse?
  • Dental – Does your horse need a teeth float?
  • General Physical including weight evaluation, diet discussion, old age changes (ie cushings), and lameness evaluation

Is your horse current on his rabies vaccination?

Rabies is caused by a virus that infects mammals and is spread through the saliva/bites by infected animals. The virus exists in several wild animal reservoirs, most commonly bats, skunks, raccoons, and foxes. After the virus is transmitted via bite, it replicates in the muscle at the site of the bite, and then travels to the central nervous system (brain and spinal cord). The virus continues to replicate in the central nervous system and then spreads through the rest of the body, including the salivary glands, which then allows transmission to other susceptible animals.

Is rabies a problem in Colorado?

In 2019, there were 173 lab-confirmed cases of animal rabies in Colorado, including canine, feline, and camelid cases. So far in 2020, Colorado has seen 71 lab-confirmed cases of rabies, including in a dog, goat, sheep, and bull. It is important to remember that because rabies is endemic in bat, skunk, and raccoon populations, these numbers don’t accurately represent the true prevalence of this disease.

What does rabies look like in horses?

While mention of rabies conjures images of a frenzied animal frothing at the mouth, clinical signs in the horse can be extremely variable, so many people may be potentially exposed before a diagnosis is made. Non-specific signs of rabies in horses can range from colic and lameness to fever and depression. There is no available testing to diagnose rabies in the live horse. When examining an un-vaccinated horse exhibiting bizarre behavior or neurologic signs, your veterinarian must consider rabies as a potential diagnosis. Signs in an infected horse progress rapidly, usually leading to death within 5-7 days. Rabies is always fatal in an unvaccinated horse.

The rabies vaccine is a core vaccine for horses, according to the American Association of Equine Practitioners (AAEP). A core vaccine is one that is essential for every horse, regardless of the horse’s lifestyle. Rabies is a FATAL disease but it is preventable through annual vaccination by your veterinarian. Because human infection is also fatal, rabies vaccination in domestic animals is a matter of public health. Any person who may have potential exposure to rabies should immediately contact their health provider.

Protect your horse- and yourself! Be sure to keep your horse’s rabies vaccination current, and don’t forget to vaccinate your barn cats and dogs!

Should You Microchip Your Horse?

Microchips: an easy, indisputable way to definitively identify a horse. In situations such as evacuations due to natural disasters or horse theft, it’s easy to see how microchip identification is invaluable. Other forms of identification are more subjective than a unique microchip number- markings change with time, tattoos become more difficult to read, and brands can be altered.

A microchip can also serve as proof of ownership, deter fraud in the sale of a horse, and identify at-risk horses at auction. But did you know the microchipping is also replacing older identification methods in breed registries? Did you know that many competitive organizations now require microchips?

Since 2013, the FEI has required microchips for competing horses. As of 2017, the Jockey Club requires microchipping for registration of Thoroughbred foals. The USEF and USHJA have required microchips since 2019. The AQHA is encouraging microchipping through the AQHA Microchip Pilot Project. The European Union has required microchips for foals since 2009. RPSI, Norwegian Fjord, and Oldenburg breed registries require microchipping.

The process of getting your horse microchipped is simple. First your veterinarian will scan your horse for an existing chip. Providing a chip is not found, your veterinarian will clean and prep the location for microchip placement. The standard location for placement is on the left side of the neck, halfway between the poll and the withers, within the nuchal ligament of the neck. The microchip is then scanned before placement to make sure the chip is read correctly. Each chip has a 15-digit unique number. The chip is inserted into the site and scanned again after placement to ensure it is read properly. Most horses tolerate this quick procedure very well, although the site can numbed with an anesthetic prior to chip placement if desired. Please contact us if you are interested in getting your horse microchipped. This procedure can be easily added to your horse’s next preventative care visit.

See the following links for more information on microchipping and show requirements:

https://files.usef.org/assets/WU5vkmldZDg/microchipping-faqs.pdf

https://equinemicrochiplookup.org/

https://www.aqha.com/-/aqha-microchip-pilot-project

https://www.ushja.org/competition/rules-and-proposals/microchipping-101

How does the smoky air affect my horse?

While the current wildfires are at some distance from us, we have not been spared from widespread smoke and poor air quality over the last few weeks. Just as poor air quality can be an irritant for us, it can also affect your horse. Unhealthy air contains irritants that can affect our eyes and nasal passages and may have a greater impact on those – both human and equine – with pre-existing respiratory conditions.

Smoke is composed of carbon monoxide, carbon dioxide, soot, nitrogen oxide, particulates, and trace minerals, as well as the primary source being burned (wood, vegetation, plastic, etc). The smoke from wildfires is high in particulate matter, which is problematic because of its extremely small size. Particulate matter easily travels to the smallest airways of the lungs, causing irritation and damage. For humans and horses, it can cause coughing, nasal discharge, and increased respiratory effort. It can also interfere with the normal defense mechanisms of the respiratory tract, decreasing immune function and the ability of the lungs to clear routinely encountered foreign materials. Horses with pre-existing respiratory conditions, such as heaves and allergies, are more sensitive to poor air quality.

How do I know if it’s safe for my horse to work?

The Air Quality Index (AQI) is the Environmental Protection Agency’s daily grade of air quality. The AQI accounts for five major pollutants: ground-level ozone, particle pollution (particulate matter), carbon monoxide, sulfur dioxide, and nitrogen dioxide. Air rated as “good” has an AQI <50. Today, August 17, 2020, Golden has an AQI of 57 (moderate), stating that air quality is acceptable, although there may be a risk for those who are more sensitive to air pollution.

Although there are currently no recommendations specifically for horses based on AQI, there are guidelines available for human athletes. The guidelines suggest removing sensitive human athletes from outdoor competition when AQI is >100 and removing all athletes from outdoor competition when AQI > 200.

What can you do to help your horse?

Be conscious of the air quality index and conditions. Go to https://www.airnow.gov/aqi/ to find the AQI in your area.

Limit exercise when smoke is visible.

Ensure adequate clean water is always available to your horse.

Limit exposure to additional dust- consider soaking hay prior to feeding.

Seek veterinary attention if your horse is showing any signs of respiratory difficulty or distress.