colics in horses. 
223 
colics. Snow eaten by horses, especially while warmed, has an 
astringent effect upon the gastro-intestiual mucous membrane, 
followed b}* congestions which often result fatally. 
Exposure to cold without suitable warm covering, especially 
if the abdomen is unprotected, often produce similar difficulties. 
It gives rise to nervous colics, congestions and indigestions, each 
of which may be followed by the already known complication. 
In this case, the action of cold is explained, first, by the functional 
sympathy which exists between the cutaneous and the digestive 
apparatus; second, by a central circulation made more active by 
the diminution in the circulation resulting from the constriction 
of the cutaneous vessels; third and especially, by reflex actions 
upon the stomach and the intestines. 
The sudden and powerful contractions produced upon the in¬ 
testines by cold may give rise at once to volvulus, or invaginations, 
or other spasmodic intestinal displacements. 
Heat, by relaxing the tissues and diminishing the tonicity of 
organs, may predispose to colics, and even to hernia, but cannot 
produce them by any direct action. 
Besides cold, any other causes likely to modify or interrupt 
the gastric-intestinal functions, are likely to give rise to indiges¬ 
tion, and simultaneously, to more or less serious congestions. 
Change of regimen, violent exercise, a lesion already present, a 
certain condition of the system, too much food, liquid or solid; 
food of bad quality, violent physical pain, excessive work too 
closely following a heavy meal, or with an empty stomach—these 
may all become so many conditions under which colics may 
appear. 
Chapter III. 
ANATOMO-BIOLOGICAL AND PHYSIOLOGICO-PATHOLOGICAL CON¬ 
SIDERATIONS UPON THE INTESTINAL TUBE OF THE HORSE. 
1. Anatomo-physiological considerations .—The digestive ap¬ 
paratus is, of course, one of the most important of the economy. 
The normal execution of its functions insures the conservation of 
the individual, and preserves, in all the apparatus of the or¬ 
ganism, the intimate solidarity which makes an organized body 
such a wonderful mass of various mechanisms, whose association 
