DIGESTION 235 



appears to be indissolubly associated with the horse, and it becomes 

 a question of the greatest practical and physiological interest to 

 ascertain the reason why digestive disturbances are so common and 

 so frequently mortal. There are certain obvious explanations of the 

 fact, but neither singly nor combined are the accepted ideas capable 

 of explaining some of the mysteries surrounding the origin of these 

 diseases. 



When muscular spasms of the intestines occur, the disease is 

 spoken of as colic ; in many cases the pain which is exhibited is in 

 no respect due to muscular spasm, and is only a symptom. Still, by 

 far the majority of intestinal cases are of this kind — viz., simple 

 muscular spasms of some part of the digestive tract, but of which 

 part we are usually ignorant. It is obvious that either the stomach, 

 the small or the large bowels may be so affected, but there are no 

 definite symptoms which enable a positive diagnosis of location to be 

 established. It is important to bear in mind the possibility of spasm 

 of the muscular walls of the stomach, for there can be no doubt it is 

 generally overlooked, and the intestines almost universally blamed. 

 The evidence supporting the view we take of the liability of the 

 stomach to disorder is afforded by the frequency of rupture of this 

 organ, not that the rupture is due to spasm of the walls, but that the 

 spasm is caused by stomach trouble, the rupture following as a 

 sequel, as detailed on p. 176. It is, however, admitted that stomach 

 spasm is far less common than spasm of the intestinal portion of the 

 tract. We would here emphasise the facts set forth on p. 203, of 

 the general inability of the horse to vomit, and the serious bar this 

 proves to relief, so much so that it is hardly going too far to say that 

 if the animal could vomit, ruptured stomach would practically be 

 unknown, and stomach trouble generally a matter of comparatively 

 slight importance. 



In connection with intestinal trouble, we are unable to say what 

 proportion the cases affecting the small intestines bear to those 

 affecting the large. We cannot during life distinguish colic of the 

 one from colic of the other. Still, there are good grounds for think- 

 ing that the large bowels are more frequently affected than the small, 

 and for the following reasons : 



1. Ingesta pass rapidly through the small intestines — so rapidly, 

 indeed, that, as mentioned at p. 213, these bowels are nearly always 

 found empty at ordinary post-mortem examinations, or the contents 

 in such a fluid condition that it is not reasonable to suppose that 

 they remain there long, from what we know of the behaviour of 

 fluids generally in the anterior part of the digestive tract. 



2. On the other hand, the large intestines always contain ingesta, 

 for the material passes along it very slowly, so that of the three or 

 four days occupied in accomplishing the journey from mouth to anus, 

 all but a few hours are spent in the large intestines. It is reasonable, 

 therefore, to assume that in cases of pure uncomplicated disordered 

 muscular action of the bowels, the large intestine in the majority of 

 cases is at fault. 



Colic is not fatal, though Percivall described such a case. The writer's 

 experience leads him to believe that death from a pure spasm of the 

 bowels is unknown, and he would emphasise the point not only for 

 the sake of accuracy, but as of value in prognosis. He believes that 

 in any case returned as dying from colic, a more extensive search 

 would have revealed some fatal lesion. There is no reason for 

 believing that the pain of colic per se is capable of causing death. 



