ISOLATING BACTERIA FROM ANIMAL TISSUES lOI 



EXERCISE LI 



ISOLATING AND IDENTiryiNG BACTERIA FROM ANIMAL 



TISSUES 



153. In making a bacteriologic investigation into the cause 

 of death in an animal or man, it is necessary to make cultures 

 from the various organs and the blood to find whether or not 

 there are any pathogenic or other bacteria present. This 

 necessitates a knowledge of making cultures from animal tis- 

 sues. In this exercise an experimental animal (rabbit or 

 guinea pig) will be provided which has died from some bacte- 

 rial disease. The purpose of this examination is to find out 

 what that disease is. To save animals, each student will make 

 cultures from but one organ. Opportunity will be afforded 

 from time to time during the course for making cultures from 

 variously diseased animal tissues. For methods of inoculat- 

 ing animals for purposes of diagnosis, see Appendix III. 



154. Work for this Exercise. — The experimental animal will 

 be furnished tied out on a post-mortem tray and the viscera 



• exposed. (Directions for the post-mortem examination will be 

 given in the course in pathology.) 



Inoculate a tube of bouillon, one of agar, and a fermentation 

 tube of glucose bouillon from either the liver, spleen, or kid- 

 ney. (In an actual investigation of an unknown disease, cul- 

 tures should be made from all of the organs, blood, and 

 lymphatic glands.) 



Make a series of 3 agar plate cultures from the same organ. 



Make several cover-glass preparations from the organ from 

 which the cultures were made. 



Stain and examine the cover-glass preparations and describe 

 the bacteria, if any are found. Stain with alkaline methylene- 

 blue and carbol fuchsin. (It is sometimes necessary to fix 



