By Scott McClure, DVM
Gastric Ulcers - Apr 1st, 04
Why Do Horses Get
Ulcers?
Equine gastric ulcers can affect
any horse at any age. Up to 90 percent of racehorses and 60 percent of show
horses, as well as non-performance horses and even foals are affected by equine
gastric ulcers. These are the result of the erosion of the lining of the stomach
due to a prolonged exposure to the normal acid in the stomach. Unlike ulcers in
humans, bacteria do not appear to cause equine gastric ulcers. Horses are
designed to be grazers with regular intake of roughage. Since the horse's
stomach continually secretes acid, gastric ulcers can result when the horse is
not eating regularly due to there being less feed to neutralize the acid.
The horse's stomach is divided
into two parts. The bottom part is glandular and secretes acid and has a
protective coating to keep it from being damaged by acid. The top portion of the
stomach is designed for mixing of the contents of the stomach and does not have
as much protection from the acid. This is the most common place to find gastric
ulcers.
Horses at
Risk
Ulcers are often a man-made
disease. Stall confinement alone can lead to the development of gastric ulcers.
When horses are fed two times per day, the stomach is subjected to a prolonged
period without feed to neutralize the acid. Furthermore, high-grain diets
produce volatile fatty acids that can contribute to the development of ulcers.
Stress (both environmental and
physical) can also increase the likelihood of ulcers. Even typical training and
recreational showing have been shown to induce ulcers within a five to seven day
period.1 Hauling and mixing groups of horses as well as horses in
training, can lead to ulcers. Strenuous exercise can decrease both the emptying
function of the stomach and blood flow to the stomach, thereby contributing to
the problem.
Many foals being
hospitalized for routine or critical care, or foals in any stressful
environment, are commonly and prophylatically placed on medication to help
prevent gastric ulceration.
Finally, chronic administration of
any non-steroidal anti-inflammatory drugs such as phenylbutazone, flunixin
meglumine or ketoprofen, can decrease the production of the stomach's protective
mucus layer, making it more susceptible to ulcers.
Symptoms
The majority of horses with
gastric ulcers do not show outward symptoms. They have more subtle symptoms,
such as a poor appetite, decreased performance and a poor hair coat. More
serious cases will show abdominal pain (colic) and/or bruxism (grinding the
teeth).
Some horses are found on their
backs or continually "cast" in their stalls since this position seems to provide
some relief from severe gastric ulceration.
Diagnosis
The only way to definitively
diagnose ulcers is through gastroscopy, which involves placing an endoscope into
the stomach and looking at its surface. To allow this, the stomach must be
empty, so most horses are held off feed for 12 to 24 hours and not allowed to
drink water for two to three hours. With light sedation and possibly a twitch,
the endoscope is passed through the nostril and down the esophagus into the
stomach. The light and camera on the end of the endoscope allow the veterinarian
to observe the stomach lining.
Treatment
and Prevention
Treatment of ulcers is aimed at
removing the predisposing factors and decreasing acid production. When possible,
horses should be allowed free-choice access to grass or hay. Environmental
factors also need to be addressed, which may include relationships with other
horses or the horse's job description. Horses that must be stalled should be
arranged so they can see and socialize with other horses as well as having
constant access to forage. Some horses appear to enjoy having a ball or other
object in the stall to occupy their time.
More frequent feedings help to
buffer the acid in the stomach. Decreasing types of grain that form the volatile
fatty acids may help some horses. The energy from the grain can be replaced by
using a feed higher in fat. In horses with lower caloric needs, free-choice
grass hay with the appropriate vitamin and mineral supplements will
help.
Medication to decrease acid
production is only necessary in horses showing clinical disease or when the
predisposing factors cannot be removed, such as with some horses in race
training or aggressive show campaigning. While antacids sound like a good idea,
to be effective they would need to be administered six to 12 times a day.
Antacids in feeds are relatively ineffective because they are ingested at the
same time as the feed, which will buffer the acid. Although many options are
available to you and your veterinarian for treating gastric ulcers, only very
few are actually labeled for this purpose. Be sure to check with your equine
veterinarian and use a product that is labeled specifically to prevent and/or
treat equine gastric ulcers and approved by the FDA.
Prevention of ulcers is key.
Limiting stressful situations, frequent feedings and free-choice access to grass
or hay is imperative. This provides a constant supply of feed to neutralize the
acid and stimulate saliva production, which is nature's best antacid. When this
is not adequate or possible, horses at greatest risk will benefit from
medication to decrease acid production.
In any case of suspected
gastric ulcers, a qualified equine veterinarian should be consulted to determine
the best course of action and treatment for the individual
horse.
[1] White G, McClure SR, Sifferman R, Holste
JE, Fleishman C, Murray MJ, Cramer LG. Effects of short-term light
to heavy exercise on gastric ulcer development in horses and efficacy of
omeprazole paste in preventing gastric ulceration. J Am Vet Med
Assoc. 2007 Jun 1; 230(11): 1680-2.
HERBAL REMEDIES FOR ULCERS
