126 BACTERIOLOGY OF MEAT AND MEAT PRODUCTS 



present I 10 per grm. in one, present 100 500 in one, present 

 5000 10,000 in one, while in the remaining sample these 

 organisms were about 50,000 per grm. In several instances the 

 brawn samples were taken from open shelves, etc., in places 

 obviously markedly exposed to dust and possibly other forms 

 of contamination. 



In regard to other made foods very little data seem to be 

 available as to their bacterial content under ordinary conditions. 



In ordinary brines used for salting meat B. coli group 

 organisms are frequently present in large numbers. 



II. The bacteriological examination of meat and meat products. 



Such an examination may be required for the following 

 purposes : 



(A) Examination for pathogenic bacteria. 



(B) To study the general bacterial content, degree of 

 bacterial contamination, etc. 



A. Examination for pathogenic bacteria. 



The examination of meat for pathogenic bacteria can ob- 

 viously only be profitably undertaken in cases in which the 

 animals have shown symptoms of disease during life or which 

 post-mortem show definite pathological lesions. It is beyond 

 the scope of the present work to describe these lesions or even 

 enumerate the diseases in animals which give rise to them. For 

 this purpose and for a description of the bacteria which may 

 have to be looked for text books on veterinary bacteriology and 

 on meat inspection and examination must be consulted. For 

 practical convenience these bacteria may be classed together 

 into three groups : 



(1) The bacteria found in septic conditions in animals. 



(2) The bacteria associated with food poisoning. 



(3) The bacteria found in special diseases such as tuber- 

 culosis, actinomycosis, glanders, anthrax, quarter-evil, etc., etc. 



The bacteria associated with food poisoning are of great 

 importance from the Public Health point of view and their 

 examination and isolation are considered in detail below. As 



