Coughing, nasal discharge and a reduced willingness to perform. Caution is advised with these symptoms! The danger of chronic respiratory disease is present, and it should not be dismissed as a simple cold. Chronic respiratory diseases are usually multifactorial diseases and can therefore be attributed to various causes. Besides genetic predisposition or previous infectious diseases, factors from the horse’s direct environment play a significant role. Inhaled dusts and gases, such as mould spores, dust particles or ammonia, can trigger excessive reactions in the respiratory tract. Diseases with an allergic component also occur regularly.
Identifying the individual triggers is of great importance in order to be able to take targeted measures for prevention and treatment. In this context, Jennifer Bormann emphasises the effects of climatic conditions: “When it comes to the issue of non-infectious respiratory diseases and allergies, the effects of climate change should not be ignored. Due to long periods of drought, the soil on pastures and riding arenas dries out considerably. The resulting dust pollution during training as well as during feeding and rest breaks is a major problem for horses. Regular watering of the facility or switching to low-dust alternatives is therefore advisable.” It is vital to include these factors in the causal research of the respective patient, says Jennifer Bormann. A thorough preliminary report regarding husbandry and feeding management as well as existing or previous diseases is essential to successfully manage horses with chronic diseases in the long term.
Coughing, nasal discharge and abdominal breathing – recognising and diagnosing symptoms.
Chronic respiratory diseases affecting horses, such as equine asthma (formerly COB, RAO/IAD), have certain similarities to human asthma. Both are multifactorial diseases that cannot be cured. For this reason, allergen avoidance in combination with medicinal support in times of worsening (exacerbation) is in the foreground.
As soon as the airways are affected, characteristic symptoms become noticeable. In addition to coughing, these include nasal discharge, which is secreted from the lungs through the nose as a result of coughing. Breathing also changes. The horses find it much more difficult to breathe, which is why they breathe faster and harder. This is called abdominal breathing. Besides the obvious symptoms, respiratory diseases also have massive effects on the lung structure. Recurrent irritation of the lungs causes remodelling processes in the structure of the tissue. Over time, more mucus-producing cells and glands are formed, and there is also increased storage of connective tissue and thickened muscles. In the long term, these changes can severely limit the functionality of the horse’s lungs. If these remodelling processes are already advanced, they are almost irreversible. To prevent this from happening in the first place, advanced diagnostic procedures are used that help to make a chronic respiratory disease visible in time.
Minimise causes and alleviate symptoms – modern therapy options
At the Hanse Equine Hospital, modern therapy options are available to treat chronic respiratory diseases affecting horses. The therapy aims to reduce inflammation in the airways, improve mucus drainage and dilate the airways. Bronchodilators and anti-inflammatory drugs can be used for this purpose. This can be done systemically (orally) or by inhalation. In some cases, anti-allergic treatment can also be effective in alleviating the body’s reaction. However, the basis of any therapy must be optimal stable and feeding management, the reduction of dust loads and good ventilation of the stable in order to minimise the triggers and thus prevent further asthma attacks. If this is not done, repeated attacks often occur soon after discontinuing the medication of a purely symptomatic treatment.
The increase in many diseases, especially those affecting the respiratory tract, can be attributed to climate change. The main causes, however, continue to be poor housing conditions, inadequate roughage quality and poor management (too little fresh air, too little exercise, etc.). Some causes can be some can be contained or even combated immediately, for others only veterinary treatment is a solution. In any case, horse owners should keep the changes of the climate in mind, focus more than ever on the well-being of the horse and consult a veterinarian at the first signs so that the progression of the disease can be stopped as best as possible.
Jennifer Bormann is a veterinarian for horses at the Hanse Equine Hospital.
She deals with the causes, diagnostic procedures and modern therapy options in connection with chronic respiratory diseases.