150 CLINICAL DIAGNOSTICS. 



purpose well) and then, with the tips of the fingers forming a 

 cone, the hand is carefully introduced into the rectum. Dur- 

 ing the examination the animal's head (if a horse) is held up, 

 and the forefoot on the side where the operator stands is 

 raised, by an assistant. Nervous or excitable horses can be 

 secured with a twitch or the operator can protect himself 

 against kicks by having the animal standing close to a stable 

 partition, the operator standing on the opposite side. The left 

 half of the abdominal cavity can be examined most satisfac- 

 torily with the right hand, the right half with the left hand. 

 Since perforations can be produced it is advisable to proceed 

 with the utmost care in making rectal examinations. 



If accumulated food masses, contraction of the rectum, or 

 the presence of gases retard the easy introduction of the hand, 

 simultaneous infusions of water should be given to facilitate 

 the operation. It is always a good plan to insert the arm 

 nearly its full length before beginning our examination. In 

 this way a long piece of the rectum slips over the arm and 

 there is less danger of pulling or straining the mesentery.' 

 This danger decreases as the length of the mesentery increases 

 anteriorly. 



Exploration per rectum is indicated in chronic colic and 

 in all cases of colic in stallions and cattle. Palpation may 

 serve to determine the following points : 



I. Fullness and position of the bowels. 

 The separate regions of the intestines can be definitely recog- 

 nized onlv when they are filled with food. Mere distention 

 with gases does not always enable us to recognize with cer- 

 tainty the identity of parts. When the bowels are empty or only 

 . partially filled with fluids or gases it may be impossible to dis- 

 tinguish between the large and the small intestine. The longi- 

 tudinal muscular bands of the large intestine of the horse are 

 the only means of differentiation, and these must be sought. 

 Manual exploration per rectum enables us to recognize food 



