1 84 



BACTERIOLOGICAL METHODS 



'rimii 



^ 



ingestion of the toxins, which might be formed outside of the 

 body and absorbed by the meat. 



d. Cadaver bacilli.— Under this head are included a variety 



of bacteria which cause putrefactive 

 changes in dead animals and in meats, 

 with toxin and ptomaine formation, 

 and to which reference has already 

 been made. 



e. Bacillus anthracis. — The anthrax 

 bacillus may occur in all food-produc- 

 ing animals, and its isolation from 

 beef and other meats may become an 

 occasional necessity in the food labo- 

 ratory. 



/. Staphylococcus group. — These 

 may occur in great abundance in liv- 

 ing animals, causing septic decomposi- 

 tion changes in tissues and organs. 



g. Streptococcus group. — ^Like the 

 Staphylococci, these organisms pro- 

 duce pyemic or septic changes in liv- 

 ing animals. 



h. Numerous other bacteria may 

 on occasion come to the attention of 

 the food bacteriologist, as the bacillus 

 of hog cholera, of swine plague, of 

 swine erysipelas and others. In this 

 connection we must not forget the 

 possible presence in beef, and less fre- 

 quently also in pork, sheep and horses, of the ray fungus {Actin- 

 omyces hovis) which is the primary cause of "lumpy jaw" in 

 cattle and which disease is transmissible to man. 



Examination of meats for the presence of encysted trichinae 

 {TricJiinella spiralis) is incidental rather than a routine in the 



Fig. 6i. — Tetanus bacillus 

 stab culture in glucose-gelatin 6 

 days old. — (McFarland, after 

 Praenkel and Peiffer.) 



