VAGINAL OVARIOTOMY IN THE MARE. 



109 



walls become erected, hard, and stand apart from each 

 other, filling the pelvic cavity, the vaginal walls resting 

 firmly against the pelvic bones at every part except at the 

 points where the bladder and rectum- intervene and these 

 organs are pressed out flat and occupy a minimum space. 

 In the quiescent state the vaginal walls are in contact and 

 from the perinaeum forward to within about 10 cm. of the 

 uterine os, the vulva and vagina are connected above with 

 the rectum by the pelvic connective tissue, while anterior 

 to this point the vagina is covered by peritoneum, and it is 

 in this area that the incision needs be made in the operation. 

 The ballooning of the vagina profoundly alters the relation 

 of this operative area, OA, Plate XVIII, and changes it from 

 the horizontal in the quiescent organ to the perpendicular 



Fig. 10 Special spraying ecraser, 55 cm. long. 



Fig. II. Colin's scalpel, 

 in the ballooned condition. These variations permit of 

 two methods of operating : I. On the ballooned organ with- 

 out anaesthesia and with the animal confined in a standing 

 position. II. In the quiescent organ in the recumbent posi- 

 tion under anaesthesia : 



I. Without anaesthesia. Secure in the stocks with the 

 head elevated, a rope over the back to prevent rearing, 

 straps beneath the body to prevent lying down, straps or 

 ropes before and behind the animal to prevent backward 



