184 HEALTH AND DISEASE 



are irregularly enlarged. In the former case they are hard and contracted 

 in consequence of having undergone a process of fibroid degeneration, or in 

 other words they have been converted into fibrous tissue. In the latter, 

 when divided with the knife, a number of cavities of different sizes are 

 found, filled with watery fluid. In this case the ovary is in a cystic con- 

 dition (fig. 527). Many of these cysts are Graafian follicles which have 

 become inordinately large, and in some instances by mutual pressure have 

 broken into each other. 



CASTRATION OF RIGS OR CRYPTORCHIDS 



It sometimes occurs that the testicles, which in the early period of life 

 are still in the belly (Plate XXXIV), fail to appear in the scrotum. For 

 some reason or other connected with development, they are either retained 

 in the abdominal cavity or stop short in the inguinal canal. 



When this occurs such an animal is said to be a rig or ridgling, or more 

 technically a cry ptor chid. It is not uncommonly observed* that one or both 

 the testicles fail to descend in the sac. In the former case the horse is 

 termed a monorchid, while in the latter he is distinguished as a double 

 cryptorchid. 



When the testicles do not "come down" into the scrotum the animal 

 has all the attributes of a stallion, and he is consequently unable to be 

 stabled with mares or turned to grass with other horses. 



Horses in this condition are frequently capable of getting foals, are 

 for the most part troublesome, and are undesirable property. Moreover, 

 their progeny are liable to be afflicted with the same malformation as them- 

 selves; in other words the defect is congenital. It becomes necessary, 

 therefore, that such animals should be castrated. 



The operation to be resorted to is for the most part simple and free 

 from danger, but where the testicles remain in the abdomen special care is 

 needed for their removal. 



In all cases it is desirable to prepare the horse for the operation by 

 restricting his diet to bran and slops for two or three days; and, for twenty- 

 four hours previously, withholding all kinds of food and restricting his water 

 to half-rations. 



This done, the horse is cast and fixed in the manner usually resorted to 

 for castration. The operation is very much facilitated by the administra- 

 tion of an anaesthetic, when every muscle is relaxed and the animal lies 

 quietly instead of struggling, as is the case where he is not under its 

 influence. 



Chloroform is undoubtedly the most useful agent in this connection. 



