762 GENITO-URINAEY ORGANS. 



The influence of castration on fattening is explained by the suppres- 

 sion of oestruiD. 



Manual Technique. — An ovariotome with a hidden blade and an 

 ro'dscur with an extra long stem are the only instruments required. 

 The animals should be prepared for some days by diminishing their 

 food supply and administering gentle laxatives. 



Acute or chronic lesions of the genital tract should be held to 

 contra-indicate operation, and it should be noted that tuberculous 

 animals are particularly liable to awkward complications. 



On the day of operation an abundant enema is given, to empty the 

 rectum, after which the vagina is washed out freely with a lukewarm 

 solution of some non-irritant antiseptic. The hind quarters, and par- 

 ticularly the neighbourhood of the anus, vulva, base of the tail, etc., 

 should be carefully washed and disinfected with a solution of lysol, 

 cresyl or carbolic acid. 



The patients are secured in a standing position, a rope being 

 passed in the form of the figure 8 around the hind limbs above the 



Fi(i. 319. — Ovariotome. 



hocks, and the animal is then firmly thrust against a wall by several 

 strong assistants. 



The operator's hands and instruments must be rigorously disinfected. 



The operation comprises three stages : 



First stage. Puncture of the vagina. 



Second stage. Finding and securing the ovaries. 



Third stage. Ablation. 



The hand is smeared with sterilised oil, and, grasping the ovario- 

 tome, is passed into the vagina, which contracts on it and on the fore- 

 arm. Within a short time, however, which may vary between two or 

 three minutes and a quarter of an hour, the vagina becomes distended 

 and its walls rigid, so that the operator is able to continue his manipu- 

 lations more easily, 'i'his is the moment for' effecting puncture, after 

 an examination of the pelvic organs through the vaginal walls. 



The blade of the ovariotome is advanced until fully exposed, and the 

 point is brought directly above the neck of the uterus, about | to Ij 

 inches from it. By a sharp movement the instrument is then thrust 

 directly forward,- dividing the wall of the vagina in the median line. 



