Mild and Severe

Working in the show horse mecca of Wellington, Fla., Meg Miller Turpin, DVM, DACIVM, of Rood & Riddle Equine Hospital, routinely treats horses with equine asthma.

Miller Turpin explains that mild to moderate equine asthma is also referred to as inflammatory airway disease (IAD), while severe asthma is best described as recurrent airway obstruction (RAO).

“Mild and moderate [IAD] are the earlier forms of the disease, which we tend to see in young and middle-aged horses,” she explains. “If caught early, it can be reversible. When aggressive treatment and essential management changes are applied to these reactive horses, then many will completely recover. In the sport horse world, we’ve improved our early diagnostic measures, which allows treatment before the condition becomes severe and irreversible.

“Unfortunately, when the disease progresses to severe [RAO], there are lung changes that are irreversible, so then we must rely on figuring out the best way to manage the symptoms,” Miller Turpin adds.

In the past, this airway condition was known as chronic obstructive pulmonary disease (COPD) or “heaves.” Many horse owners still refer to such respiratory conditions as heaves.

“The terms are often used interchangeably, but they all mean basically the same thing: mucous plugs in a hypersensitive airway,” explains Miller Turpin.

Clinical Signs of Equine Asthma

Signs of equine asthma can include:

• Coughing
• Nasal discharge
• Wheezing
• Flared nostrils when breathing normally
• Increased respiratory effort/heavy breathing
• Increased respiratory rate, even at rest
• Poor performance
• Resistance to work
• Exercise intolerance
• Anhidrosis (partial or total inability to sweat)
• Elevated heart rate during exercise or recovery
• Prolonged recovery after exercise

“We see a lot of horses with anhidrosis in Florida,” says Miller Turpin. “I’ve found that many horses with mild or moderate asthma [IAD] stop sweating, so that’s a double whammy. Sometimes you can get them to start sweating again once you get the airway issues under control.”

She finds that horses suffering from equine asthma can take much longer to recover from exercise—as long as 30 to 60 minutes to start breathing normally.

When a horse’s heart rate is much higher than it should be for the rate at which he’s working, this can indicate a lung problem is preventing the heart from getting enough oxygen to pump to the rest of the body, including muscles required for action.

Affected horses can have elevated respiratory rates as high as 50 to 90 (or more!) breaths per minute. Keep in mind, normal respiration for an adult horse is 8 to 20 breaths per minute.

Dramatically high respiratory rates combined with hot weather can be life threatening.

Causes and Triggers of Equine Asthma

Equine asthma is typically related to inhaled allergens and irritants. These can be year-round, such as dust, mold and fungal spores found in hay, straw and poorly ventilated or closed-up barns.

Other horses may only be susceptible to seasonal allergens, such as pollen encountered during specific times of year, typically spring and summer, or sometimes fall. Seasonal allergies can be easier to manage because you know when to expect a problem.

Miller Turpin finds that if horses have had a respiratory virus or a bacterial infection of the airway, this can make them more vulnerable to irritants that act as triggers.

It is believed that some horses may have a genetic predisposition to developing asthma, and when faced with environmental triggers, like dust, they will develop clinical signs.

Sensitive horses that often get hives and are very reactive to topical products and/or vaccines may be more likely to develop equine asthma.

“Horses that are stalled in cold climates in the winter with windows closed are set up for even more reactions to dust and molds,” says Turpin Miller. “Ammonia levels from urine in the stall can be toxic to the airways in a closed environments with poor ventilation. In tropical Florida, we have all this growth, bloom and mold, so even if horses receive additional turnout, there are still triggers in different grasses [and the] hay that is delivered from different areas of the United States and Canada.”

Those inhaled allergens and irritants cause inflammation, which leads to airway constriction as the tissue lining the small airways in the lungs narrows and becomes thickened. The smooth muscle surrounding these airways also constricts and tightens. Thick, sticky mucous accumulates in the airways, which also obstructs breathing.

As a result, inhaling and expelling air from the lungs becomes an effort for the horse. When the condition goes untreated, lung tissue can suffer permanent damage, resulting in irreversible loss of lung function.

Over time, horses can develop what is known as a “heave line” along the bottom of the rib cage on both sides as the abdominal muscles enlarge due to the continued effort of exhaling.

Diagnosing Equine Asthma

When a horse exhibits clinical signs that point to equine asthma, the veterinarian should do a thorough physical exam, including ultrasound of the lungs and a resting airway scope of the upper respiratory tract.

The veterinarian may also wish to perform a scope while the horse is exercising to rule out a mechanical cause, such as a displaced palate or abnormal epiglottis.

Should the horse’s heart rate be abnormally elevated, the veterinarian may use an exercise EKG to evaluate the horse under exercise.

Skin allergy testing may also be used to determine specific allergens that might be associated with inflammatory airway disease.

When equine asthma seems likely after these exams, the veterinarian will likely use a procedure known as bronchoalveolar lavage (BAL) to better define the diagnosis.

The BAL can be done without taking the horse to a clinic. While the horse is sedated, a special tube is passed through the nostril into the trachea and down into part of the lung. Sterile saline is flushed in and suctioned back out, drawing cells and mucous out with the fluid. These samples are then submitted for cytological analysis to pinpoint the most effective treatment.

Treatment Protocol

The traditional medical approach is to address inflammation with corticosteroids and, if necessary, open the airways with a bronchodilator.

The duration and amount of medication used is tailored to the specific horse.

Although systemic steroids have been the gold standard to relieve inflammation and asthma signs, these drugs can suppress the immune system and carry risks, such as laminitis.

Administering steroids via nebulizer or inhaler, instead of orally or by injection, may reduce the risk of side effects by targeting the steroids directly to the lungs.

“With competition horses, you also have to consider competition regulations and withdrawal times,” says Miller Turpin.

Some regenerative medicines are being used with promise, including stem cells. Another innovative treatment uses a patented process to filter alpha-2-macroglobulin (A2M) from the horse’s own blood. This protein has powerful anti-inflammatory properties and can be administered via a nebulizer. (Studies are still necessary to prove the efficacy of these medications.)

Supplements may also help. Miller Turpin notes that both high doses of Vitamin C and omega-3 fatty acids have lung health benefits.

It also appears that acupuncture can help breathing function in some horses with equine asthma.

The Importance of Management

Owners need to be very aware of their horse’s environment and any individual triggers. For the horse to experience ongoing relief, management changes are a crucial part of treatment protocol.

“You can treat aggressively with medications in the early stages and the horses may respond well, but if you don’t take away the triggers causing the allergy or reactive airway, then as soon as you stop the medication, the symptoms will come back, and often they will be exacerbated,” cautions Miller Turpin.

Depending on which allergens/irritants are to blame, your horse may do better when kept outside as much as possible. On the other hand, horses battling seasonal allergens may have less exposure if they’re not turned out as much that time of year.

Air quality is key. Eliminate dust and mold as much as possible. Reduce allergen/irritant exposure by:

• Using the stall with the most airflow (usually an end stall).
• Reconsider bedding (straw is often the worst choice; peat moss or cardboard may be better).
• Remove the affected horse from the barn whenever cleaning stalls, sweeping, or using a blower.

Forage Considerations

Obviously, forage is the main part of the equine diet. For asthmatic horses, however, hay can be a primary source of allergens and irritants.

Some owners find that dampening or steaming hay helps. Dry hay is not recommended, and round bales are an absolute no-no due to their high levels of dust, fungal and mold spores.

“These horses do better when you replace hay with chopped forage, pellets or complete feed,” says Miller Turpin.

Case History

The first indication Natalie Pai’s Oldenburg stallion, Mister-C, had respiratory issues was a hacking cough at the beginning of his workouts.

After Pai imported the stallion to Florida, she found he was also very sensitive to topical products, often breaking out in hives.

Miller Turpin examined Mister-C and did a series of skin allergy tests, which showed he was reactive to a wide array of allergens. She also performed airway endoscopy and a BAL. He was diagnosed with equine asthma due to severe allergies.

A2M and steroid/bronchodilator treatments through a nebulizer are part of his routine. He also gets allergy shots administered subcutaneously every two weeks. His hay is steamed to remove any dust.

“His breathing is very well managed now,” says Pai, who understands the frustration of breathing problems since she herself has allergy-induced asthma.

Key Takeaway

When a horse has breathing abnormalities, especially combined with skin sensitivities, have your veterinarian conduct an exam for possible equine asthma. Being proactive with early treatment and management changes may keep the condition from becoming severe and irreversible.

Further Reading
◆ Horse Respiratory Issues: Management of Asthma and Other Disorders
◆ Horse Allergies: Symptoms, Treatment, and Prevention

This article about equine asthma appeared in the July 2024 issue of Horse Illustrated magazine. Click here to subscribe!

The post What is Equine Asthma? appeared first on Horse Illustrated Magazine.

Ask anyone with asthma what it’s like to have an attack and words like “suffocating,” “drowning,” and “an elephant on my chest” are a common refrain. The Asthma and Allergy Foundation of America explains that asthma is a “long-term disease that causes inflammation and swelling of the airways,” meaning that the asthmatic truly cannot get enough air into their lungs. Asthma in humans has been on the rise in recent years, and it certainly seems that more horse owners are also battling the disease and other respiratory issues among their horses. Being able to identify asthma triggers is an important part of keeping people—and horses—healthy.

Once asthma triggers like dust, pollen and animal dander are identified, many human asthmatics make lifestyle changes to minimize their exposure, giving them the best chance to remain healthy. While it would seem intuitive that similar lifestyle changes would be warranted in horses, a recent study conducted by the University of Lisbon found that the majority of horse owners and managers were reluctant to implement any kind of adjustment to the horse’s routine.

Knowing that these changes are imperative to—quite literally—being able to breathe, why are some horse owners slow to adopt management changes?

Clinical Signs and Diagnosis

Lais Rosa Costa, MedVet, Ph.D., DACVIM, DABVP, director of operations for the Veterinary Emergency Response Team at the UC Davis School of Veterinary Medicine, is a boarded large animal internist whose clinical and research work has focused on respiratory diseases, especially severe equine asthma.

Though equine respiratory disease ranks second only to musculoskeletal disease in disorders that limit performance horses, signs of pulmonary disease often come on slowly, causing them to be unnoticed by owners and farm managers until clinical signs are severe.

According to Costa, signs a horse may be suffering from pulmonary disease include exercise intolerance and increased respiratory rate or increased respiratory effort. A horse suffering from asthma will often cough from increased mucus production. Any of the chronic or recurrent pulmonary diseases will cause a horse to work harder to breathe, leading to poor performance and weight loss, she notes.

It’s imperative that the root cause of horse’s health issue be defined and differentiated from other conditions, such as cardiac diseases, Costa says. This will require getting a thorough history, along with a detailed clinical examination.

“The lungs have limited ways to deal with insults, so many of these conditions manifest similarly, but the trigger is specific for the condition,” she explains.

Additional respiratory diagnostics may be needed to narrow down the source of a horse’s problem, says Kate Christie, DVM, DACVIM, an associate veterinarian with Rood and Riddle Equine Hospital in Lexington, Ky., who has a special interest in respiratory disease.

“Diagnostics are aimed at determining whether the problem is in the upper or lower airway, as well as whether the problem is infectious or inflammatory in nature,” says Christie. “The answer to these questions helps us come up with a treatment and management plan for each individual horse.”

Additional diagnostics may include bloodwork, diagnostic imaging (ultrasound examination and chest radiographs), specific airway diagnostics like endoscopy, and—if equine asthma is suspected—bronchoalveolar lavage, she explains.

Management

Once the trigger is identified, management changes to reduce or eliminate the issues causing breathing distress are imperative for the horse’s health. This can be tricky—especially in cases of inflammatory airway disease, according to Christie.

Though the “gold standard” of care would be to remove all dust and allergens from a horse’s environment, it’s simply not possible to completely eradicate these, as horses are expected to be ridden in arenas, to eat forage, and often to sleep on some form of bedding.

“Although it’s really difficult, environmental management is the cornerstone of treating inflammatory conditions of the lower airway,” says Christie. “You could provide the horse with all the medication in the world, but if the environment isn’t improved, the horse won’t respond as well [to treatment]. Our recommendations for environmental management are all aimed at decreasing exposure to airborne allergens, including dusts and molds.”

Some of the modifications need not be as overwhelming as they initially appear.

Horse Respiratory Health Myth No. 1: All horses with allergy issues should have wet hay.

Reality: Wetting hay is not the cure-all solution it was once believed to be.

“[Wetting hay] actually increases the amount of mold and exacerbates conditions like equine asthma,” says Costa. “Washing the hay, or—better yet—steaming the hay are effective ways to decrease organic particulate matter.”

Management change: While not everyone will be able to afford a hay steamer or the time to go to the barn twice a day to make cleaning the hay a reality, there are other ways to make a forage change work, according to Costa. A complete pelleted diet, pelleted hay, and haylage are a few options to consider, but no diet change should be done without the input of a veterinarian or an equine nutritionist to be sure the horse receives adequate and appropriate fiber and nutrients.

Horse Respiratory Health Myth No. 2: Bedding doesn’t matter if the horse isn’t in the stall when it’s cleaned.

Reality: A horse stalled on any type of bedding that contains contaminants that trigger a pulmonary response is at risk, and not just when the stall is being cleaned. Simply walking around in the stall can stir up enough dust to cause breathing issues.

While no horse should be kept in the stall while it’s being cleaned, asthmatic horses must be removed before the stall is mucked, and should remain out of the barn for at least one hour after cleaning.

Management change: Straw is one of the dustiest (and moldiest) types of bedding that can be used, with rice hulls and sawdust not far behind. Good quality wood shavings are not as bad.

“Severely asthmatic horses have to be bedded on shredded cardboard bedding or rubber mats with no bedding at all,” says Costa.

An even better solution? Turn the horse out 24/7.

“Many horses resolve [their breathing issues] completely with 24-hour turnout alone,” says Christie. The only time this recommendation varies is when horses are diagnosed with summer pasture associated recurrent airway obstruction (SPARAO). This condition is more common in the southeastern United States and is characterized by difficulty breathing when pastured in the summer. Pollens and other seasonal allergens are suspected to be the cause, according to Christie.

Similar to the barn-associated equine asthma, implementation of management changes is crucial for effective care of SPARAO, and without them, these horses do not respond to medical therapies, Costa says. This is a seasonal recurrent condition that can be controlled successfully with management changes and minimal medical therapies.

Horse Respiratory Health Myth No. 3: Stall location doesn’t matter.

Reality: Similar to a real estate expert, the owner of a stalled horse with breathing issues should be concerned with one thing: Location, location, location. While owners may think stalls located near doors are more uncomfortable for the horse in cold, blustery weather, the reality is the more airflow, the better.

Management change: Though horse and barn owners can get stuck in routines that are hard to change, this adjustment is one of the easier ones to implement. Moving a horse closer to a doorway, away from the indoor arena or even to a stall with a window can offer some immediate relief to the afflicted equine.

Equine asthma is a lifelong condition for which there is no cure. But be assured that even small changes can make a big impact for a horse that has a difficult time breathing.

“I often stress that [owners] can spend a lot of money on medical therapies, but these won’t make a difference if the environment is not controlled,” says Christie. “If people are able to adhere to environmental changes and keep flare-ups to a minimum, it’s less likely that the horse’s condition will progress to recurrent airway obstruction (RAO) or heaves—a much more serious and severe category of equine asthma.”

Costa also feels that management should be the No. 1 priority.

“Our job as veterinarians is to help owners and caretakers understand the importance, although sometimes challenging, of implementing management changes [that go hand-in-hand with treatment],” says Costa. “The management changes have to be realistic. Sometimes we have to be creative. The best [way to handle the situation] is to keep a positive outlook and do the best that is possible.”

While these changes may take some planning to implement, the horse’s quality of life can quite literally depend on it.

Smoke Inhalation Horses affected by barn fires and wildfires face a different set of issues that those with equine asthma and other airway diseases. Lais Rosa Costa, MedVet, Ph.D., DACVIM, DABVP, a veterinarian at the UC Davis School of Veterinary Medicine in California, has seen multiple horses affected by smoke inhalation from wildfires. “Smoke inhalation affects both the upper airways and the lower respiratory tract,” Costa explains. “Much of the acute signs of smoke inhalation injury are associated with toxic compounds released upon combustion [plus] inhalation thermal injury. “ The immediate concern is treating the acute smoke inhalation injury, which entails managing acute respiratory distress, decreasing inflammation, and preventing secondary infection. Kate Christie, DVM, DACVIM, an associate veterinarian with Rood and Riddle Equine Hospital in Lexington, Ky., notes that horses involved in fires can be severely affected by smoke and particulate inhalation—sometimes days after the initial insult to their lungs. “A massive inflammatory response may be initiated [by smoke and particulate inhalation] that causes severe pulmonary disease,” she says. “This response can be delayed from the initial exposure and is a huge problem for horses that survive barn fires. Permanent damage from smoke inhalation is also possible, and these horses may have prolonged respiratory disease that is difficult to manage.”

This article about management of horse respiratory issues like asthma appeared in the September 2022 issue of Horse Illustrated magazine. Click here to subscribe!

The post Horse Respiratory Issues: Management of Asthma and Other Disorders appeared first on Horse Illustrated Magazine.

Two potential dangers for your horse are strangles and equine herpes virus (EHV), both of which are highly contagious and can easily infect a horse at any barn, arena, or other facility. As cases increase during show and rodeo seasons, Kelli Beavers, DVM, clinical assistant professor of equine veterinary education at the Texas A&M College of Veterinary Medicine & Biomedical Sciences’ Veterinary Education, Research, and Outreach (VERO) program, housed at West Texas A&M University, gives advice on how to prevent illnesses like strangles and EHV.

Preventing Exposure

Preventing exposure to strangles or EHV starts by taking simple precautions when you travel with your horse to new facilities around other horses.

“Both of these illnesses can be transmitted by horses and by people. Most disease transmission occurs from horses that do not yet show signs of illness.” Beavers says. “Be very careful about traveling with your horse. Make sure to clean the stall you will be using before you unload everything, including your horse. Washing with soapy water is good and using a hand-held disinfectant sprayer on the walls of the stall as well. One example of a disinfectant is Virkon-S. As far as avoiding exposure, just make sure that you don’t comingle your horses with others that you are unfamiliar with.”

It is also important to ensure your horse is healthy prior to any travel. It is best to avoid any travel if your horse has signs of illness.

Beavers explains that having a quarantine barn is important for coming back home from an event.

“It’s a really great practice to protect your home farm by having a quarantine barn,” Beavers says. “If you come back from a show and realize that your horse has been at risk or exposed, you can make sure to keep other horses safe, whether it be your own horses or others sharing a boarding facility.”

Using Public Utilities

Wash racks and other areas at public facilities can be helpful but should also be approached with caution. Beavers explains how to use these amenities properly to keep your horse from becoming ill.

“When using public utilities at shows or rodeos, be sure to give yourself enough time to get done what you need done without being crowded by other horses,” Beavers says. “You can certainly wash down or disinfect any walls or railings. Make sure to keep your distance from unfamiliar horses if you can and use your common sense in those situations. You can’t completely avoid all risks, especially in common use areas. Using your own grooming equipment, and not comingling your equipment with unfamiliar people or horses can reduce the risk of these illnesses.”

Veterinarian Help

Working with your veterinarian when you suspect your horse might have contracted an illness is crucial, especially if it could be strangles or EHV. Beavers explains how veterinarian help is important to give your horse the best chance of recovery.

“When working with your veterinarian, you can make sure to stay up to date on medication and vaccinations for your horses that do travel and your horses that stay at home. With your veterinarian you can also create an individualized plan for you and your horse,” Beavers says.

Some horse shows and facilities require that a horse be vaccinated with EHV and equine influenza vaccines within a certain timeframe before the event. Be sure to check state and local regulations before traveling.

Next Steps After Horse Illness Exposure

Exposure to strangles or EHV can be shocking and even scary, so focus on the steps to a solution if this occurs.

“If your horse has been exposed, make sure that you have a plan for quarantine set up where you keep your horse. Make sure to monitor your horse for any signs of fever and take their temperature daily,” Beavers says. “If you’re taking care of sick or exposed horses, be sure and take care of them last. That way you can change clothes and get yourself clean without going back to tend to healthy horses.”

Isolate Horses with These Symptoms

It’s essential to know the early symptoms of illnesses like EHV and strangles. According to the American Association of Equine Practitioners, symptoms to watch for include:

1. Body temperature greater than 101.5°F (38.9°C)
2. Ataxia or recumbency
3. Aggressive behavior or stupor
4. Profuse diarrhea
5. Oral or coronary band vesicular or ulcerative lesions
6. Nasal discharge, coughing, and/or lymphadenopathy

Tell your veterinarian, farrier, trainer, and any other individuals who might come into contact with your horse becomes symptomatic. These professionals work with multiple horses every day, so it is important to notify them of exposure to keep other horses safe.

“It’s important to stay informed, Equine Disease Communication Center is really great because it tracks incidents and when horse illnesses occur so that you know if [strangles or EHV] is in your area,” Beavers says.

Travel with horses can bring excitement and new opportunities for equestrians of all kinds. Keep the excitement going this summer and integrate these tips into your travel routine to keep your horses safe from illness.

The post Preventing Exposure to Illness When Traveling with Horses appeared first on Horse Illustrated Magazine.

We’ve all been there. It’s a spring day of good weather, perfect for a ride. As you amble to the barn to saddle up, you hear coughing. Turning the corner, you see the coughing culprit is your horse.

In another barn, a rider grabs the grooming kit to brush her horse in preparation for the saddle. As she runs her hand over his neck, she feels, and then sees, numerous bumps, some of which have merged to form large bumps.

What is going on with these horses? Allergies.

A Teeming World of Horse Allergies

Unseen by the naked eye, the world is abundant in proteins and substances that can incite an allergic response. These allergens may be inhaled, ingested, or may affect a horse through topical contact. You’ll be tipped off to signs of trouble when you notice your horse has itching, hives, or breathing problems.

Allergies are common throughout the human and animal world, and horses are no exception. Usually, horses manage in their environment just fine without developing obvious signs that microscopic compounds are affecting them. Horse allergies happen when a horse’s immune system overreacts to a foreign protein, goes on the offense and becomes over-sensitized.

Sometimes it takes months or years of accumulated exposure for a horse to become hypersensitive; sometimes the response is more immediate and acute. Whatever specific protein causes the reaction, it sets up a cascade of inflammatory events that release prostaglandins and histamines to create obvious skin or respiratory allergic signs.

Skin Allergies in Horses

Horse allergies that manifest in the skin may result from topical contact, but also may develop from oral ingestion or inhaled particles. Aerosolized dust, mold, pollen, bedding, and insect bites are just a few of the sources that can cause itching and/or hives.

A major cause of itching starts with the bite of insects called Culicoides, also known as midges or no-see-ums. While the midges tend to feed on the abdomen, a horse displays an allergic response to the midge saliva by aggressively rubbing his tail, hindquarters, neck and mane due to intense itching. Those areas become raw, crusty, and inflamed, with substantial hair loss.

Some breeds and lines of horses tend to be particularly allergic to midges, such as Morgans, Icelandics and Arabians. The solution relies on moving the horse away from areas favorable to midge breeding, like ponds, wetlands and slow-moving streams.

Fly sheets are important, but they should have belly bands of netting material. Bringing a horse inside at dusk and dawn also helps to reduce midge exposure, as that is their preferred feeding time.

In contrast to an itching reaction (pruritus), hives aren’t typically itchy but herald a definite sign of exposure to some kind of allergen. Hives tend to be soft swellings that indent when you push in with your finger, called pitting edema.

They may be variable in size, sometimes coalescing into one big welt when several are close together. Inhaled allergens also can cause hives, referred to as atopic dermatitis.
Contact dermatitis is also not unusual. One example that occurs fairly commonly is hives from contact with pine bedding. If there is a suspicion that bedding is a problem, substitute paper bedding or a different source of pine bedding to see if the hives resolve.

Some shampoos or fly sprays can cause skin irritation and hives, as can laundry detergent residue or dirt on a saddle pad. On rare occasions, a horse with a fungal infection called ringworm may develop hive-like reactions around a fungal lesion.

Hives can develop acutely and disappear just as quickly. Sometimes they persist long after the allergen is removed from the environment. In difficult cases, it may be necessary to medicate the horse with a short course of a corticosteroid like dexamethasone or prednisolone, which are effective anti-inflammatory medications.

Certain feedstuffs can set off a skin reaction, although food allergies are not that common. If it is a food allergy, however, it’s often a challenge to determine the exact food or oral substance that is the culprit.

This may need to be done through a process of elimination: eliminate all food and supplements and start by feeding only grass hay, although diet changes may need to be done slowly. Check with your vet. After a couple of weeks with no signs of hive lesions, add in one more food element and wait a week or two before adding in another. This may help pinpoint the cause.

Supplements tend to be the likeliest culprit, far more than hay or feed materials, although alfalfa has been known to cause allergic reactions.

Respiratory Allergies in Horses

Respiratory allergies can affect horse performance by impacting breathing and comfort, especially during exercise. A horse with a respiratory allergy often has a dry cough or wheezing that amplifies when he is eating or exercising. There may be a chronic or intermittent nasal discharge, as well.

Respiratory health is at risk when horses are placed inside barns, especially those with poor ventilation, and/or are exercised in indoor arenas. Many toxic compounds are aerosolized to circulate in the air in those environments: endotoxin (part of the cell wall of Gram-negative bacteria) in manure, ammonia vapor from urine-soaked bedding, mold spores from hay, or hay dust filtering down when stored in lofts above the stalls or arena. Arena footing can also contribute to respiratory irritation.

The best solution is to minimize a horse’s time indoors and instead turn him out as much as possible. Better yet, arrange full-time outdoor living with run-in sheds to protect against inclement weather. Soaking or steaming hay before feeding helps tamp down dust and mold.

If barn living is all you have available, then implementing good ventilation is very important. Use appropriately placed fans, open windows, and open barn doors to keep fresh air circulating. Store hay in a building separate from horse housing.

Another important strategy for respiratory health is to keep your horse on a regular immunization schedule, especially against respiratory viruses. Equine influenza virus is known for causing long-term respiratory damage, including development of equine asthma. Discuss an appropriate vaccine schedule with your veterinarian.

Once a horse develops equine asthma, a variety of medications, including inhaled and/or oral bronchodilators, can help improve his comfort and ease of breathing. It is much easier and more effective to apply an ounce of preventive strategies for respiratory health than a pound of cure to treat after the fact.

Equine Anaphylaxis

In an instance where a horse’s immune system develops a profound and severe reaction, a horse can experience life-threatening anaphylaxis. With that in mind, it’s important to contact your vet immediately when seeing signs of an allergic response, particularly if your horse is having difficulty breathing and/or there is swelling of his face and muzzle or limbs and belly.

If your horse has a known allergy to a medication, such as penicillin or a non-steroidal anti-inflammatory drug (NSAID) like phenylbutazone or flunixin meglumine, it’s critical to place caution signs on the horse’s stall door and paddock to prevent accidental administration of potentially deadly drugs.

People with allergies wear neck tags or bracelets to convey this critical information, but for horses, it’s necessary to post signs in obvious places. Advise your barn manager and staff, friends and veterinarians who may deal with your horse.

Allergies can be troublesome to resolve, so observe and monitor every facet of your horse’s environment. With knowledge about potential problems, you can deter allergic problems before they begin.

The post Horse Allergies: Symptoms, Treatment, and Prevention appeared first on Horse Illustrated Magazine.

Dealing with respiratory problems can be stressful, especially since they can impact overall health and performance. In addition to veterinary care and a management plan, the right combination of ingredients in an equine respiratory supplement can also help support healthy lung function in horses with respiratory issues, so you and your horse can enjoy your rides!

Equine respiratory supplements primarily work by supporting healthy tissues and structures throughout the respiratory tract, including the trachea and the lungs. Additionally, because seasonal allergies can cause difficulty breathing, some respiratory supplements contain herbs to help support a normal immune response (allergic reactions are a result of hyper-sensitivity in the immune system).

When looking at a respiratory supplement, there are certain ingredients to look for. MSM provides support for a normal response to inflammation throughout the body, including in the respiratory tract. Meanwhile, grape seed extract, super oxide dismutase, vitamin C, and bioflavonoids offer support for respiratory cell health. Finally, there is N-acetyl cysteine, which has been shown to help protect airway tissues from seasonal respiratory conditions.

SmartPak’s SmartBreathe Ultra Pellets provides comprehensive support to help soothe and maintain your horse’s airways. This equine respiratory supplement offers those ingredients, along with spirulina, a freshwater blue-green algae that has been reported to help horses prone to respiratory issues, and DHA, a specific type of omega-3 from fish oil, which was shown in a recent study to provide benefits to horses with airway syndromes.

Further Reading

• August 2020 SmartPak SmartTip of the Month: Supporting the Horse’s GI Tract
• July 2020 SmartPak SmartTip of the Month: SmartSalt and SmartLytes for Salt and Electrolyte Loss
• June 2020 SmartPak SmartTip of the Month: Important Ingredients for Joint Support for Horses
• May 2020 SmartPak SmartTip of the Month: How to Help a Nervous Horse
• All SmartPak SmartTips

The post September 2020 SmartPak SmartTip of the Month: Supplements for Equine Respiratory Health appeared first on Horse Illustrated Magazine.

Learn more about the differences between terms used for respiratory disease in the horse, such as heaves, chronic obstructive pulmonary disorder (COPD), bronchiolitis, small airway disease, recurrent airway obstruction (RAO), inflammatory airway disease (IAD), and most recently, equine asthma.

For nearly as long as horses have been domesticated, the relationship between barn confinement and respiratory disease, such as equine asthma, in the horse has been recognized. This relationship is intuitive, especially when we consider that deep in the lung, where the blood takes up oxygen, the barrier between the outside air and the horse’s circulation is as thin as a couple of cells.

The surface area of this gas-exchange region of the lung has on average a surface area of 2,500 square meters (26,900 square feet), equal to nearly half a football field. The response of the lung’s immune system to inhaled air results in a number of diseases in both humans and horses. Many of the occupational respiratory diseases in humans are associated with agriculture due to exposure to organic dusts. Dust in agricultural settings, including the horse barn, are rich in substances such as endotoxin and fungi that can drive inflammation.

Depending on when the conversation took place, owners consulting their veterinarians about respiratory disease in their horse will have heard many terms applied to this problem: broken wind, heaves, chronic obstructive pulmonary disorder (COPD), bronchiolitis, small airway disease, recurrent airway obstruction (RAO), inflammatory airway disease (IAD), and most recently, equine asthma. Along the way, distinctions have been drawn between those horses that develop difficulty breathing at rest (heaves, RAO, severe equine asthma) and those that do not (IAD, mild equine asthma). While potentially leading to confusion for the horse owner, the changing terminology actually reflects improvements in veterinary knowledge.

While the term COPD was applied to reflect the obstruction or blocked airflow that can occur in severe cases, this term was discarded due to the differences with the human disease. In humans, COPD is mainly a consequence of cigarette smoke and is characterized by structural changes within the lung that are absent in the horse. While the terms recurrent airway obstruction and inflammatory airway disease are descriptively accurate, they are not necessarily terms that immediately help the horse owner to understand the disease process.

A More Relatable Term for Respiratory Disease

Due to its many similarities with the human disease, the term equine asthma has most recently been adopted. Like human asthma, equine asthma is triggered by inhalation of dust that contains allergens and other irritants, and like human asthma, the cough and difficulty breathing can be reversed in the short term by medications, often delivered by inhalers, or in the long term by removal from the offending dust. Also similar to asthma in humans, the response of the horse’s airway to inhaled dust can vary widely. In some highly susceptible horses, inhalation of even small amounts of dust in the barn environment or airborne allergens (e.g., pollen, molds) at pasture can cause severe inflammation and difficulty breathing due to the accumulation of mucus and narrowing of the airways. There is no known cure for these “severely asthmatic” horses, and they require special management for the duration of their life span.

In other horses, the inflammation is milder, with occasional coughing and decreased performance. Respiratory problems in these “mildly asthmatic” horses often become apparent only when the horse is asked to perform athletically and may resolve over time. Those horses with mild asthma do not necessarily go on to become severely asthmatic.

While susceptibility varies widely, any horse (or person) exposed to enough dust will develop inflammation in the airway. In the case of stabled horses, dust exposure is mostly due to hay. Those horses with severe asthma often require that hay be completely removed from the diet and that the horses be removed from confinement to the barn altogether.

In the milder cases, decreasing the dust released from hay by soaking or steaming may improve airway health. As soaking has a number of draw backs, high temperature steaming is becoming the preferred method to reduce exposure to the dust from hay. At Purdue University College of Veterinary Medicine, we use a Haygain hay steamer, which has been shown to reduce respirable dust by 98%.

Article provided by Haygain, manufacturers of Haygain Hay Steamers and ComfortStall Orthopedic Sealed Flooring. For more information, visit www.haygain.com.

Further Reading

• Breakthrough in Identifying Equine Asthma Allergens
• Waiting to Inhale
• Ask the Vet: Allergy Symptoms in Horses

The post Learn More About Respiratory Disease in the Horse for National Asthma and Allergy Awareness Month appeared first on Horse Illustrated Magazine.

An accurate diagnosis is the foundation for effective treatment of any equine health issue and especially so for allergic conditions that impact equine respiratory function, such as identifying equine asthma allergens. Haygain’s long-standing commitment to research has recently resulted in significant progress toward identifying which of various allergens trigger inflammatory responses and other allergy symptoms in the horse.

The study involved horses with severe equine asthma. As its name implies, this is the condition on the most severe end of the equine asthma spectrum, the umbrella term adopted by the veterinary community in 2016 to encompass the range of respiratory conditions. At the mild and moderate end of the spectrum is the much more common Inflammatory Airway Disease (IAD), known to affect over 80% of the active sport horse population. Horses with IAD are not necessarily more susceptible to contracting the more severe manifestations, but many do. Severe equine asthma is commonly referred to as Recurrent Airway Obstruction (RAO) or heaves. By any name, it’s a debilitating condition that affects 14% of horses in the Northern Hemisphere.

It’s common knowledge that allergens found in fungi, bacteria and arthropods (mites, etc.) cause this condition by triggering the body’s inflammatory responses.

Which Allergen or Allergens?

Samuel White, PhD candidate, MSc, BSc, and his co-researchers utilized the latest developments in computing power and robotic technology to produce a microarray, a microchip-based testing platform that enabled evaluation of almost 400 potential allergens at a single time. This was the largest scale allergen assessment in severe equine asthma in horses to date. The results established a wide range of previously unidentified allergens and highlighted fungi and mites as the main reactants.

This initial study established a sound platform for future diagnostics by providing a reliable, fast and repeatable method for screening of potential allergens. Crucially, it enables targeted allergen-avoidance regimes, which are the cornerstone to treatment.

Know Your Equine Asthma Allergens

White, the lead researcher, is an equine science faculty member at Nottingham Trent University in Nottingham, England. An applied immunologist, he specializes in equine asthma and allergies, focusing on the identification of biomarkers, protein allerginicity and the development of novel diagnostic techniques.

The study was accepted and published by The Journal of Veterinary Internal Medicine in July of 2019. “The last four years of my PhD have been both challenging and exciting in equal measures!” says White. “The funding provided by Haygain has enabled significant scientific advances in both the understanding and future diagnosis of severe equine asthma. It is very rewarding to see our initial development of this technique published in one of the highest-ranked veterinary journals globally. I look forward to publishing further aspects of this project in due course.”

White’s research supervisor, Professor Meriel Moore Colyer, is equally excited about the findings. “This research has produced a highly specific and accurate method by which to identify severe equine asthma allergens in horses and is definitely the way forward for better diagnosis and accurate treatment,” says Colyer. “The high number of allergens tested and the international aspect of the samples collection means that these results are applicable worldwide.

“Being able to identify what an individual horse is allergic to will help owners choose management regimes and employ the most effective pre-feeding treatments to minimize the horse-allergen interaction and reduce the negative impact of this performance-limiting condition.”

Collaboration is Critical

Haygain’s technical director Becky James explains the horse health company’s motivation for funding equine research in general and this study in particular: “Collaboration in research is important when pushing boundaries and using innovative techniques such as the microarrays,” says James. “It’s exciting that so many specialists from around the world were involved: a collective group from the UK, France, Switzerland and the U.S.”

Along with advancing management and treatment protocols for all horses with or at risk of severe equine asthma, the study results confirm earlier research that fungi are a major cause of equine respiratory problems. In addition to dust, mold and bacteria, high-temperature hay steaming greatly reduces fungi in hay.

“We are proud to have supported this research project to better understand which allergens cause Recurrent Airway Obstruction,” James notes. The broader context of the investigation is the reality that over 80% of active sporthorses suffer some degree of airway disease, often without obvious symptoms. “It’s important to support general understanding of all degrees of equine asthma,” James concludes. “It’s all part of our effort to prevent or successfully treat this all-too-common condition.”

For more information on Haygain, and its high-temperature hay steaming process and products, visit www.haygain.com.

Read the full study, “Development of a comprehensive protein microarray for immunoglobulin E profiling in horses with severe asthma.”

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