Page 38 - 31 August 2012

SCOPING
Upper Respiratory Abnormalities
by Jill A. Mixer, DVM
As a horseman, do you ever ask yourself “Why isn’t my
horse finishing the race
like he should? I know
he’s fit!” If a thorough lameness exam reveals
no problems, you could
be dealing with an upper respiratory problem.
These problems quite often go undiagnosed in the young Quarter Horse racehorse.
Some horsemen have a misconception that an upper respiratory abnormality will cause the horse to make a noise when breathing hard...
For whatever reason, Quarter
Horse trainers do not perform endoscopic exams
as routinely as Thoroughbred trainers. This could be because Thoroughbreds primarily run longer distances and proper airflow would seem to be more important, but it is just as important to a young Quarter Horse in training.
Some horsemen have the misconception that an upper respiratory abnormality will cause the horse to make a noise when breathing hard, but that is not true of all abnormalities. In some cases, the abnor- mality has to become extremely severe before they begin to make a noise during exercise.
One such abnormality is an aryepiglottic entrap- ment or more commonly called an “entrapped epi- glottis.” (See Fig. 2) Sometimes the only indication of
Fig. 1: In a normal pharynx, the triangular-shaped epiglottis has serrated edges.
soft palate (normal position)
an “entrapped epiglottis” is lack of performance, nervousness or “dreading” going to the gates,
or severe exercise induced pulmonary hemorrhage (EIPH). It is a good idea to get an endoscopic exam when your horse bleeds
from the nose after exercise to determine if there is an
upper airway obstruction caus- ing the bleeding from the lungs. If an “entrapped epiglottis” is left
undiagnosed, an ulcer can develop on the free edge of the aryepiglottic fold or in the center of
it and then it can adhere to the epiglottis eventually causing a growth resembling cauliflower and also deforming the epiglottis creating permanent breathing problems. With early detection, a minor surgery can be performed and recovery time is only a couple of weeks.
Another upper respiratory problem which can range from mild to severe is a condition called pharyngitis or sometimes referred to as “blisters” by horsemen. People have only two tonsils in their throat to fight infection whereas horses have multiple follicles (or tonsils) in their throat to ward off infection. When these become inflamed, they look like small “blisters” all over the roof of the pharynx and even down onto the soft palate in more severe cases (Fig. 3).
Fig. 2: In an “entrapped” epiglottis, the serrated edges cannot be seen.
36 SPEEDHORSE, August 31, 2012
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