I. -.8 



TUBERCULOSIS 



intestinal mucosa, 

 primary tubercular 

 ulcers may develop 

 or they may pass 

 into the mesenteric 

 lymphatics or the 

 portal vein. It may 

 happen that the 

 bacteria may be car- 

 ried by means of 

 the lymph or blood 

 stream and lodge in 

 any part of the 

 body, such as the 

 brain, kidneys, 

 spleen, testes, ovar- 

 ies, bones, joints, 

 and subcutaneous 

 and intermuscular 

 glands and serous 

 membranes. The 



Fig. 25. Dorsal aspect of bovine lungs. a-a\^^'^^^^'^^ ^t hand, 

 highland /eft caudal lobes. b-b\ r. and I. ven- however, seems to 

 tral lobes. c-c\ first and second right cephalic show that in a laro-e 

 -lobes. C-, left cephalic lobe, c, trachea, x x, ^ajoritv of cases 

 region most frequently involved in the earliest , . ' . . 



stages of pulmonary tuberculosis. The lesious P^'i^ary lesions 



nre usually at this stage embedded in the lung are (i) in the lungs 

 tissue. (Smith.) or the lymphatic 



glands draining them, (2) in the lymphatic glands about the 

 head, (3) the intestines and mesenteric glands, and (4) in the 

 portal glands or liver substance itself. Primary lesions some- 

 times occur in the generative organs and udder. 



It not infrequently happens that the apparent primary 

 lesions occur on the pleura, peritoneum, meninges or synovial 

 membranes while the organs remain free from disease. In such 

 cases the lesions consist of many tubercles varying from 

 one to ten or more millimeters in diameter or of bunches of 

 closely set tubercles which are more or less flattened or irregular 



