THE DIGESTIVE SYSTEM, 



269 



cathartic dose. Small doses of liquor arsenicalis are 

 admissible. 



In dealing with the effects of irritant poisons^ we shall 

 have to touch upon Oastro- enteritis as it especially occurs 

 in adults, but there is a disease known under this name 

 to which calves are subject. In the young animal the 

 abomasum is the largest of the stomachs, and it is only 

 after weaning that the rumen comes to so greatly ex- 

 ceed the remainder of the gastric mass. The milk 

 accumulates in the fourth stomach and undergoes coagu- 

 lation, after which it is digested. For the proper per- 

 formance of these processes it is necessary that the milk 

 be taken in moderate quantity, and be of good quality. 



Fig. 53. — Stomachs of the calf. a. Rumen, c. Abomasum (considerably 

 the larger). (Simonds.) 



Pail-fed calves are apt to obtain too much milk, also 

 animals brought up by a foster-mother are apt to indulge 

 in excess in this respect, and disorder is promoted by 

 want of the healthy stimulus which exercise is to diges- 

 tive processes. Thus, the stomach becomes laden with a 

 hard mass of curd, which proves a source of irritation, 

 and causes death from the effects of impaction. Inflam- 

 mation sets in, extends to the intestines, and thus gives 

 rise to an acrid irritating discharge, whence the disorder 

 is termed *' wJiite scour '^ or " shit.'' Another form of 

 accumulation of material in excess in the abomasum is 

 seen in partially weaned calves, when the first and third 

 compartments have not been able to properly prepare hay 



