ANIMAL CASTRATIO^f. 139 



Preparniion of the animnJ. — No general preparation 

 is required, except one, which may be regarded as of 

 local effect, but is not to be overlooked. This consists 

 in the evacuation of the bowels by means of a rectal 

 injection, in order that the arms of the surgeon may 

 not become unnecessarily soiled during the opera- 

 tion. The animal is secured on her feet by being 

 placed in a narrow stall to prevent her from moving 

 from side to side, the floor of the stall having an in- 

 clination forwards, in order to prevent the pressure 

 by gravitation of the intestinal mass towards the 

 posterior parts of the abdomen. 



It is understood that antiseptic measures are here 

 also indicated. Disinfection of the vulva, of the 

 vagina, and thorough aseptic condition of the instru- 

 ments, of the hand and arm of the operator. 



The operation is completed in two steps, of which 

 the first is the incision of the vagina, and the second 

 the extirpation of the ovaries. 



THE INCISION IN THE VAGINA. 



This is made in the following manner. The ope- 

 rator introduces the speculum with his right hand, 

 through the vulva, into the vaginal cavity, and care- 

 fully passing in his left hand, well oiled, directs and 

 introduces the little prolongation A of the speculum 

 into the centre of the neck of the uterus, gently 

 pressing upon it in order to keep it in place. In 

 using the original dilator, the opening of the branches 

 must be so regulated as to put the walls of the vagina 

 upon the stretch. Or, if he uses the modified specu- 

 lum, he pushes the instrument downwards and for- 

 Trards, and bj this motion distends the upper wall 



