OOPHORECTOMY. 239 



and the instrument into the peritoneal cavity, necessitating a much 

 larger vaginal wound. 



In the standing position the operation resembles that in the cow. 

 Should a trevis or an operating table not be at hand, the mare, half 

 an hour before operation, should be given a full dose of chloral 

 hydrate and afterwards placed in a stall. The recumbent position 

 is preferable in most cases, and to prevent straining general anaes- 

 thesia is employed. The rectum must be entirely emptied. Hard 

 faeces in the rectum expose the bowel to injury when the vagina is 



A.W. 



Fig. 268. — Longitudinal incision in a vertical plane through the posterior 

 abdominal region, pelvis, and urino-genital organs of a cow. The section 

 is somewhat to the right side of the median plane. The figure illus- 

 trates the second stage of ovariotomy : the hand is grasping the left ovary, 

 o. Ovary, u. Uterus, v. Vagina, e.h. Right horn of the uterus 

 (cut through). l.h. Left horn of uterus. b.u.l. Broad uterine 

 ligament. R. Rectum. bl. Bladder, p. Pelvis, a.w. Abdominal 

 wall. e.s. Excavatio superior, e.r. Excavatio recto-vaginalis. e.v. 

 Excavatio vesico-vaginalis. e.i. Excavatio inferior. 



incised. As in the cow, the vaginal wall is punctured above the 

 os uteri, after preliminary cleansing and disinfection of the vagina, 

 the vulva, and its neighbourhood. The injection of irritating fluids 

 into the vagina must be avoided. Even one per thousand sublimate 

 solution, especially if used warm, may irritate the mucous membrane 

 and cause straining, which hinders operation. The best disinfectant 

 is a cold solution of lysol or carbolic acid, one per cent. 



The hand carrying the knife is passed into the vagina and directed 

 towards the convex uteri. At first, depending on the degree 

 of anaesthesia, the hand may be closely embraced by the vagina, 

 but by moving the hand to and fro for a few seconds the vaginp 



