CHAPTEE XIII. 



Post-mortem examination of animals— Bacteriological examination of the 

 tissues— Disposal of tissues and disinfection of instruments after the exam- 

 ination. 



DuEiNa the bacteriological examination of the tis- 

 sues of dead animals, certain rigid precautions must be 

 observed in order to avoid error. 



The autopsy should be made as soon as possible after 

 death. If delay cannot be avoided, the animal should 

 be kept on ice until the examination can be made, other- 

 wise decomposition sets in, and the saprophytic bacteria 

 now present may interfere with the accuracy of results. 



When the autopsy is to be made, the animal is first 

 inspected externally, and all visible lesions noted. It 

 is then to be fixed upon its back upon a board with 

 nails or tacks. The four legs and the end of the nose, 

 through which the tacks are driven, are to be moder- 

 ately extended. Plates are now to be made from 

 the site of inoculation, if this is subcutaneous. The 

 surfaces of the thorax and abdomen ai-e then to be 

 moistened to prevent the fine hairs, dust, etc., from 

 floating about in the air and interfering with the work. 

 An incision is then made through the skin from 

 the chin to the symphysis pubis. This is only a skin 

 incision, and does not reach deeper than the muscles. 

 It is best done by first making a small incision with a 

 scalpel, just large enough to permit of the introduction 

 of one blade of a blunt-pointed scissors. It is then 

 completed with the scissors. The whole of the skin is 



