BACTERIUM TUBERCULOSIS AVIUM 429 



countered. The smegma bacillus and the butter bacillus 

 are especially liable to lead one into error of diagnosis. 

 This is less apt to be the case with the comparatively rare 

 lepra bacillus. 



BACTERIUM TUBERCULOSIS AVIUM (MAFFUCCI), 

 MIGULA, 1900. 



Synonyms: Bacillus tuber/culosia avium, Maffucci, 1891; Mycobacter- 

 ium tuberculosis avium, Lehmann and Neumann, 1896. 



From time to time fowls are known to suffer from a form 

 of tuberculosis that in a number of ways suggests human 

 or mammalian tuberculosis. The bacillus causing the disease, 

 the so-called bacillus of fowl tuberculosis, bacillus tuber- 

 culosis avium, while simulating the genuine bacillus tuber- 

 culosis morphologically, differs from it both in cultural 

 and pathogenic peculiarities. Thus, for instance, it develops 

 into much longer and somewhat thinner threads; grows 

 rapidly on media without glycerin or glucose; does not 

 grow on potato; develops as well at from 42° to 43° C. as 

 at 37° to 38° C.;^ its virulence is not diminished by cul- 

 tivation at 43° C; development on artificial media begins 

 in from six to eight days after inoculation; young cultures 

 on solid media are whitish, soft, and moist, becoming yel- 

 lowish and slimy with age; it is somewhat more resistant 

 to drying and high temperatures than the bacillus of mam- 

 malian tuberculosis; the results of its pathogenic activities 

 are almost always chronic, are rarely located in the lungs 

 or intestines, but are especially frequent in the liver and 

 spleen; the lesions are conspicuously rich in bacteria, do 



1 The normal body-temperature of fowls ranges between 41.5° and 

 42.5° C. 



