Similar
to human indigestion, tympanic colic occurs when the intestines become distended
with gas.
Causes:
The
over-production of gas within the intestines, commonly the result of gorging on
new grass in the spring. If a horse is turned out onto grass for long periods
after being stabled over the winter, it may not be able to digest this quantity
of grass and may produce excessive quantities of gas. Likewise, any sudden feed
change may induce tympanic colic. Mistakenly providing moldy or spoilt feeds is
another common cause. Other causes include improperly or not sufficiently cured hay and grains,
lawnmower clippings.
Signs:
Gas within the
intestines cause stretching of the bowel wall. This is very painful and thus
animals often colic violently. Heart and respiratory rates may be as high as
60-70 beats or breaths per minute and guts sounds are often absent since the
muscle in the stretched intestinal wall is unable to contract. On rectal
examination, balloon-like distension of the intestines may be felt and large
amounts of gas may be freed when a tube is passed into the stomach. Peritoneal
tap is normal and fecal production is variable, although large amounts of wind
may be passed!
Treatment:
Liberation of gas
from the stomach following ‘tubing’ may cause all pain to subside. Some
light exercise such as walking out in hand or lungeing for 10 minutes at the
trot may help the animal to ‘pass wind’ and the colic to resolve, however,
if the horses (usually young foals) act too violently, it is best to keep them
in the stall to prevent injuries to themselves and to people around. Often painkillers (analgesics) and intestinal relaxants may be necessary.