Page 635 - The Veterinary Care of the Horse

The effects of respiratory disease

When a horse succumbs to infectious or allergic respiratory disease, the quiet, relaxed pattern
VetBooks.ir of breathing is disturbed. This is because the diameter of the airways is reduced by:

•
excessive production of mucus or pus
• inflammation and swelling of the epithelial cells lining the airways

• spasm of the smooth muscles in the airway walls.

More effort is needed to draw the same volume of air through the narrowed tubes and gas
exchange is less efficient. The smallest airways may become completely blocked. Prompt

treatment is required to prevent permanent damage occurring to the delicate lung tissues.
Diseases of the respiratory system include:

• viral infections

• bacterial infections

• fungal infections
• allergic respiratory disease

• parasitic infections.

Veterinary examination

When you call a vet to examine a horse with respiratory disease, the vet will need

information about the horse’s management, including details of the:
• diet, e.g. type of concentrate, quality of forage

• type of bedding

• grazing and worming history
• vaccination status

• nature of work the horse performs

• recent exposure to respiratory disease, e.g. attendance at shows, sales etc.

The vet’s clinical examination of the horse may include:

• observation of the rate and character of breathing while the horse is resting and relaxed

• taking the temperature

• listening to the chest with a stethoscope (known as auscultation) for any abnormal
wheezing or crackling sounds