388 Tuberculosis 



(c) Cattle. Cows and heifers receiving intrapleural 

 and intra-abdominal injections of the human bacilli usually 

 gain in weight and show no symptoms. When examined 

 post mortem, circumscribed chronic lesions were found. 

 Those inoculated with the bovine bacillus lose weight, suffer 

 from constitutional symptoms, and show extensive lesions 

 at the necropsy. Two- thirds of the cattle inoculated experi- 

 mentally with the bovine bacillus die. 



Lesions. In general the lesions produced by the bovine 

 bacillus were rapid, extensive, and necrotic. Many bacilli 

 are present. Those produced by the human bacillus are 

 more apt to be productive, chronic, and unaccompanied by 

 large numbers of bacilli. The bacilli of human tuberculosis 

 produce lesions with many giant-cells; those of bovine 

 tuberculosis, lesions with rapid coagulation-necrosis. The 

 lesions resulting from the intravenous injection of human 

 bacilli into rabbits resembled those observed by Prudden and 

 Hodenpyl* after the intravenous injection of boiled, washed 

 tubercle bacilli. 



From these data it is evident that the bovine bacillus 

 is by far the more virulent and dangerous organism. While 

 the human bacillus infects cattle with difficulty, the bovine 

 bacillus infects animals with great readiness. 



At the International Congress on Tuberculosis, held in 

 London, 1901, Koch expressed the opinion that bovine 

 tuberculosis was not communicable to man. The matter 

 is of the utmost importance to the medical profession and 

 of far-reaching influence upon many important sanitary 

 measures that bear directly upon the public health. 



Koch's opinion, being opposed to all that had been believed 

 before, received almost universal disapproval. The papers 

 by Arloing,f Ravenel,J and Salmon contain evidence show- 

 ing that under certain conditions bovine tuberculosis can 

 be communicated to man. 



Ravenel || has reported three cases of accidental cutaneous 

 inoculation of bovine tuberculosis in man. All were veter- 



* "New York Med. Jour.," June 6-20, 1891. 



f " Lyon Med.," Dec. i, 1901. 



t "Univ. of Pa. Bulletin," xiv, p. 238, 1901; "Lancet," Aug. 17 

 and 19, 1901; "Medicine," July and Aug., 1902, vol. vm. 



Bull. No. 33, Bureau of Animal Industry, U. S. Dept. of Agricul- 

 ture, 1901. 



|| " Phila. Med. Jour," July 21, 1900. 



