TUBERCULOSIS IN THE CAT. 247 



of the testicle having been met with in the cat. Tuberculosis of the 

 peritoneum is even less common than that of the pleura. The parietal 

 layer is usually free ; the lesions are limited to the epiploon and 

 mesentery, which appear thickened and dotted over with fine granules. 

 The peritoneal sac may contain more or less abundant, clear or 

 purulent serosity, either poor or moderately rich in bacilli. 



External tuberculous lesions, with and without ulceration, have 

 several times been noted. I described two cases in a preceding 

 lecture. 



The paths of infection are multiple, but the two principal are the 

 digestive and respiratory mucous membranes. 



In most cases the bacilli enter the organism through the intestinal 

 mucous membrane. In this way cats which ingest offal, milk, or other 

 material derived from tuberculous animals, food infected by a tuber- 

 culous patient, or purulent sputum, may become infected. Nevertheless 

 cats may also contract tuberculosis by living in rooms in which the 

 atmosphere is charged with tuberculous dust. We know that in all 

 species infection occurs readily through the respiratory mucous mem- 

 brane. Passage of bacilli through other mucous membranes, and 

 through the skin, is exceptional. 



Contrary to the most widely held opinion, and to what one would be 

 led to believe from the conditions of life and habits of the cat, tuber- 

 culosis in this animal is most frequently of human origin. In more 

 than three fourths of the cases where the probable method of contagion 

 could be traced, infection from man appeared indicated. The animals 

 belonged to tuberculous subjects or lived in intimacy with them. In 

 this connection the following interesting observation was made to me 

 by my colleague, M. Darras, a veterinary surgeon in Paris : 



" Mme. X — , concierge, had for four years owned a family of six 

 cats, all of them superb, vigorous animals, in very good health. 

 Towards the end of 1894 these animals began to grow thin and cough. 

 The oldest one soon died. The post-morteui examination, made at 

 Alfort, showed that death had resulted from tuberculosis. Both the 

 thoracic and abdominal organs were affected. Shortly afterwards a 

 female kitten, which had become very thin, showed multiple disease 

 of lymphatic glands ; the glands in the neck were especially large. It 

 died at the end of a month. Post-vwrtem examination showed no 

 intestinal or pulmonary lesion, but the mesenteric glands were enlarged, 

 and the spleen (which \vas of great size) displayed very numerous 

 granulations. No bacteriological examination was made. At the end 

 of six months two other cats which had fallen away in condition. 



