DIGESTIVE APPARATUS. 157 



Method of procedure. To make a thorough examination it 

 is often necessary to introduce the arm full length. A shirt with- 

 out a sleeve can be worn to advantage on such an occasion. [After 

 carefully paring the finger nails] the arm should be well covered 

 with oil, or soap (castor oil answers the purpose well) and then, 

 with the tips of the fingers forming a cone, the hand is carefully 

 introduced into the rectum. During 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 excit- 

 able horses can be secured with a twitch or the operator can pro- 

 tect 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, simul- 

 taneous infusions of water should be given to facilitate the opera- 

 tion. 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 only 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 arc 

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

 Manual exploration per rectum enables us to recognize food 



