220 



TUBERCULOSIS. 



ioid cells and in leucocytes ; but these are by no means 

 frequent sites. 



The above statements, however, apply, only to tuber- 

 culosis in the human subject, and even in this case there 

 are exceptions. In the ox, on the other hand, the presence 

 of tubercle bacilli within giant cells is a very common 



FIG. 60. Tubercle bacilli in giant-cells, showing the radiate arrange- 

 ment at the periphery of the cells. Section of tubercular udder of cow. 

 Stained with carbol-fuchsin and Bismarck-brown. x 1000. 



occurrence ; and it is also common to find them in con- 

 siderable numbers scattered irregularly throughout the 

 cellular connective tissue of the lesions, even when there is 

 little or no caseation present (Fig. 60). 



In tuberculosis in the horse and in avian tuberculosis 

 the numbers of bacilli may be enormous, even in lesions 

 which are not specially acute ; and considerable variation 



