VETERINARY SCIENCE AND PRACTICE. 395 



mental cages are carefully described. The number of experiments conducted was 

 sufficient to justifj' the drawing of quite comprehensive conclusions. The author's 

 general conclusions may be summarized as follows: 



The tu])ercle bacillus of bovine origin exhibits quite constant and persistent jiecul- 

 iarities of growth and morphology, by means of which it may be differentiated from 

 the form of tubercle bacillus commoidy found in man. Pure cultures ol bacilli 

 from the 2 sources differ dei'idedly in pathogenic power, and this proi)erty affords 

 another means of differentiating the 2 forms. The bovine tubercle bacillus is much 

 more pathogenic than that of human origin for all species of experimental animals 

 which were tested, with the possible exception of hogs, which appeared to be very 

 susceptible to both forms of the bacillus. Tuberculous material from cattle and from 

 man corresponds closely to pure cultures of tubercle bacillus from the 2 sources in 

 regard to its comparative i)athogenic power for all animals which were tested. The 

 author believes that he is justified from evidence at hand in assuming that the bovine 

 tubercle bacillus possesses a higher degree of pathogenic power than the human 

 bacillus for man as well as the domesticated animals which have been tested. 



Detailed notes on the numerous experimental cases are presented in tabular form. 

 From these tables it is seen that in general the infection of experimental animals 

 from tubercle bacillus of human origin was only slight or took place after a longer 

 incubation period than in the case of infection from the bovine tubercle bacillus. 

 In many cases, it should also be observed, no infection whatever took place. 



The average life of guinea pigs inoculated with human tubercle liacillus was more 

 than twice that of those which wei-e infected with bovine bacilli. The rabbits which 

 were inoculated with human tubercle bacilli gained in weight and had to be killed 

 in order to conduct the post-mortem examination, while extensive infection was pro- 

 duced in other rabbits from inoculation of bovine tubercle material. 



Influence of the toxons of tuberculin upon the development of experi- 

 mental tuberculosis, S. Arloing and Descos {C'ompt. Reiid. Sue. Biai. Paris, 54 

 {1903), A^o. 3, pp. 52, 53). — The authors had already demonstrated that it was pos- 

 sible to destroy a considerable part of the toxon of tuberculin by the addition of a 

 definite quantity of antituberculin serum and that the persistent toxicity was due tc- 

 the presence of toxon. Further experiments were conducted on rabbits and guinea 

 pigs. The experimental animals were divided into 3 lots, and all were inoculated 

 with tuberculosis at the same time. The first lot had received preventive inocula- 

 tions of tuberculin and serum previous to the inoculation of tuberculosis; the third 

 lot received curative inoculations of the same mixture, after inoculation with 

 tuberculosis; while the second lot was simply inoculated with the tubercle bacilli, 

 and served as a check upon the other lots. As the result of these experiments the 

 authors conclude that tuberculin neutralized by serum and reduced in its content of 

 toxons does not give better results in combating tuberculosis than tuberculin or anti- 

 tuberculin serum used separately. Inoculation for the purpose of prevention or cure 

 appeared to favor the development of tubercular lesions and to augment their 

 extension. When employed for curative purposes the method seemed to hasten 

 death, if the tuberculin was not sufficiently neutralized. It was concluded, there- 

 fore, that the toxons of tuberculin pos.sess a certain amount of toxicity, and also the 

 property of favoring the development of experimental tuberculosis. 



Chemotactic properties of various tuberculous sera, F. Arloing {C'ompt. 

 Bend. Soc. Biol. Paris, 54 {1902), No. 17, j)p. 556-558) .—The author studied the serum 

 of normal cows, of cows inoculated hypodermically with tuberculous cultures, cows 

 affected with spontaneous tuberculosis of a generalized form, and goats inoculated 

 with a fluid obtained by filtering tuberculous material. It was found as a result of 

 these experiments that antituberculous serum is endowed with a jiositive chemotactic 

 action which is not possessed by the serum of healthy cows or that of cows in 

 advanced stages of tuberculosis. In experiments on goats it was found that repeated 



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