Your horse’s respiratory system is a complex machine that powers many internal processes that are critical to their health, performance and overall wellbeing.
In extremes of heat and cold, the equine respiratory system faces a number of seasonal threats and irritants, in addition to the stresses of exercise in extreme temperatures and dusty environments.
In this article, we take a closer look at some of the common equine respiratory health conditions that are caused by or exacerbated in extreme heat and dry arid climates to help you support your horse’s respiratory health.
The Horse’s Respiratory System
A healthy respiratory system in the horse serves a number of functions. You’re of course familiar with the basics, being intaking oxygen and expelling carbon dioxide. Did you know, it also plays an important role in immunity against bacteria, viruses and fungi.
Some of the other incredible functions that your horse’s respiratory system is capable of include filtering out thrombi and emboli, which are the technical terms for blood clots and air bubbles, as well as thermoregulation and indicating pain.
Purpose-built for exercise, the equine respiratory system is designed to move large volumes of air in and out of the lungs. At rest, a healthy horse will take around 12 breaths per minute, which may increase to more than 100 breaths during strenuous exercise!
The anatomy of the equine respiratory system may be divided into two parts: the upper and lower airways. The upper airways involve the nostrils, larynx and trachea, and the lower airways include the lungs.
Diseases and other conditions affecting equine respiratory health can also be divided between the upper and lower airways and we’ll delve into these further.
Your horse’s respiratory system is the third largest organ in their body, following the skin and gastrointestinal tract, and is arguably the most important for athletic performance. Respiratory conditions are the second leading cause of poor performance in horses.
Regardless of whether your horse is at the height of their athletic career, ridden for leisure or a cherished paddock ornament, supporting their respiratory health is imperative for maintaining their health and overall wellbeing.
Infectious Respiratory Diseases
When discussing common respiratory diseases in horses, we must first define the difference between infectious and non-infectious respiratory diseases.
There are a number of infectious respiratory diseases that can occur year-round and in most climates. A variety of respiratory diseases are caused by bacterial and viral infections, which can be prevented through regular vaccination programs. These include:
- Equine influenza
- Equine herpesviruses
It’s important to mention these as infectious respiratory diseases in horses are common and can quickly spread from horse to horse if not managed properly.
Also, the initial symptoms of many airway diseases are remarkably similar. Precautions should always be taken if you suspect your horse has a respiratory-related health condition and if it turns out to be infectious, biosecurity measures should be put in place.
Non-Infectious Respiratory Diseases
Non-infectious respiratory diseases are thankfully not transferred between horses, but their effect on your horse’s health and athletic performance can be crippling.
Many non-infectious respiratory diseases in horses are caused by hypersensitivities to allergens which may flare as the seasons change. Three non-infectious respiratory diseases that may be exacerbated by heat are:
- Inflammatory airway disease, which typically affects younger horses.
- Equine asthma, previously known as recurrent airway obstruction (RAO), chronic obstructive pulmonary disorder (COPD) or heaves, which occurs in older horses.
- Summer pasture-associated obstructive pulmonary disease, which is seasonal.
All three of these non-infectious respiratory diseases manifest in the lower respiratory tract.
Inflammatory Airway Disease
Inflammatory airway disease is not a disease in and of itself, it describes a group of inflammatory conditions of the lower respiratory tract. It can occur in horses as young as one year of age and may affect up to 50% of athletic horses.
Allergens and atmospheric pollutants are two possible causes of inflammatory airway disease which are worsened in hot calm weather. The associated decrease in air quality and increase in air pollutants in such climates also affects older horses with equine asthma.
Just like us, horses can suffer from asthma. In fact, a recent study showed that 54% of horses suffer from a respiratory allergy and this number is rising due to increasing temperatures and prolonged pollen seasons.
While a number of factors are involved in equine asthma, including genetic predisposition, it’s clear this airway disease is triggered by exposure to respirable particles, such as pollens, which peak during warmer months.
Summer Pasture-Associated Obstructive Pulmonary Disease (SPAOPD)
A recently discovered airway disease, which has also been linked to allergens that spike during periods of heat and high humidity, is Summer pasture-associated obstructive pulmonary disease, also called Summer pasture allergy.
Its full name is quite a mouthful, so we’ll stick with the shortened acronym. SPAOPD is a form of severe equine asthma that arises following exposure to pastures in late Spring to mid-Autumn when pollen count is high.
A Few Tips for Equine Respiratory Health
As horse owners, we need to understand that anything which increases allergens in the air will in turn, increase the likelihood that your horse will develop an allergic reaction.
There are a few simple steps we can take in our daily routines to minimise the impact of allergens and lower disease risk, including:
- Vaccinate your horse regularly
- Water dusty surfaces before working your horse
- Remove your horse when mucking out their stable
- Place feed at ground level to allow their head to lower
- Feed wet hay and soaked dry feed to reduce dust particles
- Provide adequate ventilation in stables, arenas and when travelling
- Choose a bedding that is low in dust
- Increase turnout (your vet can assist with a management plan for SPAOPD sufferers)
- Use the Flexineb E3 for optimum respiratory health
Disclaimer: This article is not intended to replace professional veterinary advice. Always consult your veterinarian if your horse as any health-related issue or is exhibiting symptoms.
- Equine respiratory health
- Equine respiratory system
- Infectious airway disease