HERNIA OF THE INTESTINE.
Causation. This is due to the same cause as hernia of the rumen—a blow which, while injuring the skin only to a trifling extent, damages the abdominal walls, and even the intestine itself.
Symptoms. The hernia is situated in the lower or lateral zone of the right flank.
The symptoms present some peculiarities. The loop of intestine which has passed through the aperture in the abdominal walls becomes distended by the accumulation in it of semi-liquid alimentary material, and, acting by its own weight, produces a hernial sac, which steadily grows in size. The skin being very mobile, and the subcutaneous connective tissue very loose, they readily yield and become separated. The inflammatory symptoms disappear, and are followed by a swelling under the skin, which is compressible all over, and can readily be reduced, whereupon it gives forth a gurgling noise, or a sound as of borborygmus. Reduction is easier when the animal is lying on its left side, or on its back.
Complications. Strangulation of the small intestine is the only serious complication in this form of hernia, but it is very dangerous. It occurs frequently when the rupture is somewhat highly-placed on the lateral portion of the abdominal wall, because the loops of intestine have a tendency to descend, thrusting away the skin owing to the weight of material which they contain.
The partially digested food is apt to accumulate in the herniated loop, and hernial engorgement, the first phase of strangulated hernia, rapidly occurs.
Fermentation is set up in the half-digested food, and putrid gases are generated. Thus the hernial sac becomes distended, the vessels are compressed, circulation is arrested, and gangrene supervenes.
At this time gurgling sounds and a certain degree of tympanitic resonance may be noted. These are followed by all the symptoms of intestinal strangulation—namely, intense colic, which suddenly disappears when the intestine becomes mortified, absolute loss of appetite, stoppage of rumination, constipation, suppression of defæcation, tympanites, and peritonitis.
The diagnosis is comparatively easy at an early stage, owing to the peculiar character of the soft swelling, which is easily compressible. At first there may be difficulty in distinguishing it from a collection of serous fluid, but the facility with which the swelling can be reduced removes any doubt.
The prognosis is always serious, on account of possible complications, due to strangulation of the herniated loop. When the hernia is chronic, reduction is much more difficult, there being, as a rule, adhesions between the intestine and the hernial sac.