COLICS OF THE HOBSE. 



143 



General causes of colics. 1. Predisposition, The special 

 proneness of the horse to colic is owiug to the particular anatomical 

 disposition of the stomach and intestines. The small dimensions 

 of the stomach, the oblique insertion of the œsophagus upon this 

 viscera, the presence of membranous folds, the fulness of the left 

 pouch, are peculiarities which render vomiting extremely difficult 

 in this animal ; thus the contents of the stomach, if solid or gaseous, 

 cannot be evacuated through the œsophagus. The length of the 

 mesentery, the great volume and mobility of the large abdominal 

 reservoirs, favor the changes of relation of these organs and the 

 accumulation of alimentary matters in their interior, and accord- 

 ingly these are very frequent accidents. 



We must also point out the extreme sensibility of the terminal 

 fibres of the intestinal and peritoneal nerves, which become easily 

 stimulated under the influence of numerous trivial causes. 



Finally, the frequent aneurism of the first colic artery is again 

 an important etiological factor ; by producing thrombi or emboli of 

 the intestinal arteries it plays a very important rôle in the pathology 

 of colics. 



2. Colds. At times the action of cold is felt upon the surface of 

 the body ; it is particularly to be feared at the time of shedding the 

 coat and during damp days, especially when winds from seaward 

 and rain follow a long dry spell. This action is produced directly 

 upon the mucous membrane when the animals ingest very cold 

 drinks, or food covered with frost or ice. Adam has noticed fre- 

 quent colics in horses after drinking water at a temperature of 5° C. ; 

 the same water at the temperature of 7° C. was harmless. 



3. Overloading the stomach. This happens generally when the 

 horses eat too fast, when the various alimentary substances which 

 compose the ration are given them too rapidly ; also when the food 

 is not in proportion to the work performed (on resting days, Sun- 

 days, etc.). It is also produced when the animals consume heavy 

 alimentary matters which are hard to digest, such as grains (rye)^. 

 hay cut too short, fresh hay and oats, raw potatoes, etc., and 

 especially when mastication is insufficient. 



Immediate work after meals is a frequent cause of colic. 



4. Dirty alimentary mattei^s. Muddy hay and grass covered with 

 sand, dust, or mould; also straw, oats, and bread covered with 

 mould ; dirty drinking-water containing earthy matters. 



5. Abundant production of gas in the stomach after the ingestion. 



