C. DISEASES OF THE FETUS. 



During intra-uterine life the fetus is subject to various diseases, 

 either of the entire body or of parts, ■which, at the time of partu- 

 rition, may cause more or less serious dystokia. These consist 

 largely of dropsy of cavities or organs, by which means a portion 

 of the fetus becomes greatly increased in size ; or a general 

 dropsy of the entire body, anasarca, occurs. 



I. Hydrocephalus. 



Hydrocephalus consists essentially of a distension of the lateral 

 ventricles of the brain with lymph. The fluid may be of any 

 amount, and upon its volume depends the degree of dystokia 



f'v' ; V ■ ■■ ■ - ' 





Fig. 122.] [Hydrocephalus. Calf. (Harms). 



which it may produce. In the calf and foal it reaches, in many 

 cases, the amount of 4 to 5 gallons, and then constitutes a rather 

 serious impediment to the expulsion of the young. 



The cerebral hemispheres are virtually absent, while the cere- 

 bellum and medulla oblongata are usually present in an appar- 

 ently normal condition. The enormous distension of the lateral 

 ventricles, with the prevention of the formation of cerebral 



