CHA.PTEE XIII. 



Post-mortem examination of animals — Bacteriological examination of 

 the tissues — Disposal of tissues and disinfection of instruments 

 after the examination — Study of tissues and exudates during life. 



During bacteriological examination of the tissues 

 of dead animals certain precautions must be rigidly- 

 observed in order to arrive at correct conclusions. 



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, otherwise decomposition sets in, and the sapro- 

 phytic 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 moderately extended. Plates are now to be 

 made from the site of inoculation, if this is subcuta- 

 neous. The surfaces of the thorax and abdomen are 

 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 with a scalpel 

 an incision just large enough to permit of the intro- 

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



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