Page 683 - The Veterinary Care of the Horse

TREATMENT

If the horse has experienced a severe bleed, surgery should be done as soon as possible to tie
VetBooks.ir off and occlude the affected artery. Any delay could result in the horse dying from a fatal

haemorrhage. Following the surgery, antifungal powders are sprayed onto the roof of the
pouch through in-dwelling catheters for at least a week.

PROGNOSIS

This depends on the extent of any nerve damage. Although the fungal plaques can be treated,
some horses have permanent nerve damage and have to be destroyed. Where there is no

nerve damage and the damaged artery is successfully ligated, the prognosis is good.

EQUINE ASTHMA SYNDROME (EAS)

There are a number of conditions in which horses develop inflammation of the lower airways
that is not caused by infection. These include recurrent airway obstruction (RAO), summer
pasture associated obstructive pulmonary disease (SPAOPD) and inflammatory airway

disease (IAD). These diseases have now been reclassified as equine asthma syndrome (EAS)
with two subcategories depending on whether or not the horses show increased respiratory

effort at rest. Horses affected by severe equine asthma show increased respiratory effort and
include those previously diagnosed with RAO and SPAOD. Horses with mild equine asthma
breathe normally at rest and include those formerly diagnosed with IAD.

In the following description, the older names for non-infectious lower airway disease

have been used as most readers will be familiar with these terms.

RECURRENT AIRWAY OBSTRUCTION (RAO)

Recurrent airway obstruction (RAO) is one of the names given to a common respiratory
disease syndrome that affects horses and ponies. It is also known as chronic obstructive
pulmonary disease (COPD), recurrent airway disease (RAD), ‘heaves’, and ‘broken wind’.

Affected horses are usually 7 years of age or older.

Causes

It is caused by inhalation of dust from the environment when a horse is stabled. Hay and
straw contain fungal spores which trigger an allergic response which causes inflammation