Once a horse has developed heaves, he will always be more susceptible to flare-ups when he encounters even small amounts of the substances that affect him.

that inhibits the functioning of the small airways.

• Mucus buildup: flammation caused by neutrophils

stimulates the overproduction of

thicker, stickier mucus than is found in

normal horses.

The type of in-

Once a horse has developed RAO,

he will always be more susceptible to

flare-ups when he encounters even

small amounts of the substances that

affect him. “I explain it to horse owners

by comparing this to human allergies,”

says Laurent L. Couetil, DVM, PhD,

DACVIM, of Purdue University. “If you

are severely allergic to cats, a few cat

hairs may cause as much reaction as

the whole cat. If you walk into a room

where there was a cat, you can tell---

because you respond to it. Some horses

equately to prevent heaves, but I’ve only

had two that needed medication once in

a while because respiratory problems

would flare up. The rest have done fine

just with our management, with no

medication. They live at the farm, and

when they are not in a study they are

outdoors 24-7 with just a shelter in their

pasture. They are fed a complete pelleted

feed during the winter when there is not

enough grass.”

Your best advisor for addressing your

horse’s particular situation is, of course,

your veterinarian. And you may need to

do a little detective work to identify ele-

ments in a horse’s environment most

likely to trigger RAO. But, to help you get

started, we’ve compiled a list of the mea-

sures most commonly recommended to

reduce the stress on horses with heaves.