CHAPTER XVII. 



Tuberculosis Microscopic appearance of miliary tubercles Diffuse 

 caseation Cavity-formation Encapsulation of tuberculous foci 

 Primary infection Modes of infection Location of the bacilli in 

 the tissues Staining-peculiarities Organisms with which bac- 

 terium tuberculosis may be confounded: bacterium leprte ; bacterium 

 smegmatis Points of differentiation Acid-proof bacteria Actino- 

 myces Actinomyces bovis, Actinomyces Israeli, Actinomyces madurte, 

 Actinomyces farcinicus, Actinomyces Eppingeri, Actinomyces pseudo- 

 tuberculosis. 



BACTERIUM TUBERCULOSIS (KOCH), MIGULA, 1900. 

 Synonym : Bacillus tuberculosis, Koch, 1882. 



LOCAL OR GENERAL TUBERCULOSIS. Should the 

 animal succumb to neither of the septic processes just 

 described, then its death from tuberculosis may reason- 

 ably be expected. 



When this disease is in progress alterations in the 

 lymphatic glands nearest the site of inoculation may 

 be detected by the touch in from two to four weeks. 

 They will then be found enlarged. Though not con- 

 stant, tumefaction and subsequent ulceration at the 

 point of inoculation may be observed. Progressive 

 emaciation, loss of appetite, and difficulty in respiration 

 point to the existence of the general tuberculous process. 

 Death ensues in from four to eight weeks after inocula- 

 tion. At autopsy either general or local tuberculosis 

 may be found. The expressions of tuberculosis are so 

 manifold and in different animals vary so widely the 

 one from the other, that no fixed law as to what will 

 appear at autopsy can ct priori be laid down. 



The guinea-pig, which is best suited for this experi- 

 ment because its susceptibility to tuberculosis is greater 

 and more constant than that of other animals usually 



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