Respiratory disease (COPD) in horses and what to do about it
There is a steady increase in the awareness of one’s horse’s health among equestrians. As a result, many horse owners have already had to face respiratory diseases, as these are very common nowadays due to modern horse keeping. How to recognise if your horse is suffering from respiratory disease and what you can do about it is covered in this blog post.
Chronic obstructive pulmonary disease (COPD) is the most commonly used term to describe an inflammatory obstructive disease in the lower airways of the horse. The most common symptoms of this complex syndrome are lowered performance, coughing, nasal discharge (mucus, usually white or yellow – a few drops of clear watery discharge after training are nothing to worry about though), dyspnea (shortness of breath) and in severe cases even weight loss.
Many equestrians become confused with the many different names used to describe this syndrome, such as chronic obstructive bronchitis (COB), heaves, broken wind, alveolar emphysema, chronic pulmonary disease, small airway disease, chronic obstructive lung disease, chronic bronchitis, and recurrent airway obstruction (RAO). These all describe the same symptoms and syndrome, but COPD still is the most commonly used term.
Symptoms to watch out for
As previously stated, there are common symptoms to watch out for when figuring out if your horse might be struggling with COPD. Things to look out for are:
Have you noticed decreased performance and your horse seeming intolerant and more stressed than usual during exercise? This is normally the first indication of problem's with your horses airways. Unfortunately, these symptoms can be an indicator of a variety of issues and therefore further investigation by a veterinarian will be necessary.
Does your horse frequently cough while eating hay or during training, especially when advancing into a higher gait? Does food or mucus come up with the cough? If the answer is yes, definitely consult a veterinarian as all of the cases in which this happened, that I witnessed while working with a specialist in this field, were rather severe cases that required veterinary care and supervision.
White or yellow nasal discharge is a clear indicator of respiratory disease. The consistency can vary from thick, slimy, foamy to watery. Naturally, the horse's lungs have a self-cleaning mechanism to protect the horse from pneumonia caused by foreign particles. For this purpose, the lungs are lined with a respiratory mucous membrane, which binds dirt particles and transports them out of the respiratory tract by a "conveyor belt mechanism". If the respiratory tract is exposed to large amounts of ammonia, dust, mold, or pollen further defense reactions occur, such as increased mucus production to remove the foreign particles. However, if there is too much mucus production, the condition can be aggravated as the thick mucus "clogs" the airways.
Different consistencies of nasal discharge, thick and slimy to foamy to watery (© Michelle Botha – Gut Bisdorf Solekammer)
Another common symptom can be that your horse is experiencing shortness of breath. A normal breathing frequency of a calm horse is 8 to 12 breaths per minute. You can observe your horse’s breathing frequency by watching their chest or rib cage move in and out, if you can’t see this, you can place your hand in front of one of the nostrils of your horse to feel the air move in and out for 15 seconds and then multiply it by four to get the breathing frequency of your horse. If it is higher than the normal frequency, your horse could be experiencing shortness of breath which leads it to breathe quickly but shallow. Many barns have a stethoscope lying around which you can use to listen to your horse’s breath. Are the breaths deep or shallow? How does it sound, clear or is there crackling or squeaking?
Does your horse have a “heave line”? In chronic respiratory diseases, the elasticity of the lung and diaphragm tissue is often reduced, so that the negative pressure is no longer sufficient for effective breathing. In this case, the abdominal muscles are needed to enable the horse to fully exhale from the narrowed airways. Due to this strong use of the straight abdominal muscle (musculus rectus abdominis), it becomes very defined, creating the so-called "heave line”, which runs from the horse's flank towards the navel.
From experience I can say that unfortunately there are some horses, whose breathing sounds perfectly fine but who were suffering from a severe case of COPD, therefore consulting a veterinarian if you have any doubts is always the safest path to take.
Since horses are flight animals, they rely heavily on their large lungs, which reach up to their last ribs. Thus, during riding the equestrian sits exactly on the horse's lungs and they are enclosed by the saddle. Horses suffering from a chronic respiratory disease can therefore often show a change in behaviour during riding, as the horse's breathing is restricted even more by the rider and saddle which can lead to the horse reacting aggressively, fearful or even panicky. Oftentimes riders will also notice the horse only wanting to walk with a very high or low head position as these allow them to breathe better.
If you suspect your horse is having trouble breathing always consult a veterinarian and if necessary, have them perform a bronchoscopy.
What can you do?
It is important to realize that COPD is a chronic disease meaning that it will never go into full remission and therefore your horse will have to be treated for the rest of its life. However, many simple management changes can have a significant impact on your horse’s well being.
The foundation of your horse’s life is the hay you feed it. You always want to have hay that has been analysed in a lab and has been cleared to fulfill the high-quality standards your horse needs to be healthy. Most cases of COPD are caused by a hyper reaction or allergy to mold and dust which can be found in hay that does not fulfill the quality standards your horse needs. “Dusty” hay usually isn’t just that, dusty, but actually the “dust” are millions of fungal spores which cause allergies and respiratory diseases in both horses and humans, therefore high-quality hay should be one of the top priorities when keeping horses. Some equestrians also like to feed silage as it is less dusty. This, however, more often than not is full of mold and thus not suitable.
Nonetheless, even the best hay will be a little dusty as it is a dried natural material. By “washing” or at least wetting your hay right before feeding, the amount of dust your horse will breathe in is significantly reduced, making it much safer and more pleasant for your horse to consume. Keep in mind that you want to wash it right before feeding and not leave it lying around for multiple hours, as mold could develop more easily this way.
If your horse is stabled, you want to make sure that it is stabled on low-dust shavings or pellets and eats a low-dust diet. Furthermore, keep dry hay and straw as far away as possible to not irritate the lungs more. Often the symptoms of COPD go into remission when the horse is pastured and not exposed to hay. Thus, pasturing your horse if you have the opportunity can already better your horse’s condition drastically.
Does your horse show some of the symptoms of COPD? Consider investing in an inhaler. Nowadays there are multiple different types available to fit your needs, such as inhalers to fill an entire stall with mist, ultrasonic inhalers with a battery that you can put onto your horse while taking a walk and many more. There are different (medicated) substances (e.g. special salt solutions) you can fill into the inhaler to help soften and remove mucus from your horse’s lungs and calm the respiratory mucous, allowing your horse to breathe more freely again. Doing an inhalation session daily or every other day right before exercising your horse can be of great value for your horse.
Horse in a salt chamber being treated for COPD (© Michelle Botha - Gut Bisdorf Solekammer
Continued treatment at home with an ultrasound inhaler (© Michelle Botha)
It is important to keep in mind that it can be difficult to figure out if your horse is struggling to breathe freely, therefore always consult a veterinarian to see what is going on and how to treat it.