320 A MANUAL OF BACTERIOLOGY 



admitting that the bovine bacillus does infect man, it by 

 no means follows that all such cases of infection are derived 

 from a bovine source, for humans might infect one another 

 with the bovine bacillus ; this possibility never seems to 

 be considered. 



The occurrence of tuberculosis in the domestic animals raises 

 points of practical importance, especially the occurrence of infection 

 from the consumption of meat and milk from diseased animals. 

 There can be no doubt that the carcase of an animal extensively 

 affected with tuberculosis, especially if wasting has occurred, should 

 be condemned as unfit for food, and likewise all parts in which 

 there are tuberculous deposits. But it becomes an important 

 question for the community, financially as well as from a hygienic 

 point of view, as to the method of procedure with the meat from a 

 beast comparatively slightly affected with tuberculosis an enlarged 

 gland or two, and a few nodules on the pleura. No doubt the ideal 

 method in such a case is the condemnation and destruction of 

 the whole carcase, be the amount of tubercle ever so little ; but 

 from financial considerations this procedure is hardly practicable 

 on account of the large amount that would have to be paid in 

 compensation. Experiment has demonstrated that the tubercle 

 bacilli are practically confined to the tuberculous areas and are 

 extremely rarely met with in the muscular tissue, and these portions, 

 therefore, it might seem, could be eaten with impunity, especially 

 as they would be cooked before consumption. As regards swine, 

 however, it is generally held that tuberculosis anywhere condemns 

 the whole carcase. 



The report of the first Royal Commission on Tuberculosis, how- 

 ever, indicated two dangers. Firstly, in cutting up a carcase the 

 butcher will most likely use the same knife throughout, and in 

 this way may infect the meat with tuberculous matter by smearing 

 with the knife. Secondly, cooking cannot be depended upon to 

 destroy the bacilli unless the joints are under 6 Ib. in weight ; when 

 the weight is above this the temperature in the interior may not 

 rise sufficiently high. Evidently one of the first measures to be 

 taken is the abolition of private slaughter-houses and the establish- 

 ment of municipal abattoirs where the meat would have to be 

 passed by competent inspectors. In this way all badly affected 

 carcases would be condemned, and those only slightly affected could 

 be separately dealt with and special precautions taken to eliminate 

 tuberculous pieces, etc. 



