





INOCULATION OF BIRDS 305 



Intra-venous inoculation of the avian bacillus leads to the death of the 

 fowl in a fortnight to three weeks with a disease of the Yersin type (vide also 

 p. 301). [In the experience of the English Commission it was generally longer 

 5 to 6 weeks.] 



(6) Those who believe that the human and avian tubercle bacilli belong to 

 different species hold that the fowl cannot be infected with the human tubercle 

 bacillus : but this conclusion [in the opinion of many] can no longer be 

 maintained in view of the experiments carried out by Koch, Nocard and 

 Cadiot, and Gilbert and Roger. These observers [appear to] have shown 

 that the fowl becomes infected with tuberculosis as the result of the ingestion 

 of human tuberculous material and of pure cultures of human tubercle bacilli. 

 It is [by some considered as] certain that the fowl may become infected by 

 the ingestion of the sputum of phthisical persons. 



It has to be remembered that fowls often resist infection with bacilli of 

 human origin and that when infection does occur the disease is chronic and 

 leads to the formation of tubercles in the internal organs. [Fowls are resistant 

 to mammalian tubercle bacilli of whatever source when inoculated intra- 

 peritoneally, sub-cutaneously and by feeding, but frequently succumb to intra- 

 venous inoculations. Tubercle bacilli killed by exposure to steam at 100 C., 

 whether avian or mammalian, may produce however similar effects when 

 inoculated intra-venously into the fowl ; these effects are therefore not a true 

 tuberculosis but are to be attributed to the toxic action of the bacilli (F. 

 Griffith, for the English Commission).] 



F. Cold-blooded animals. 



Frogs and fish do not appear capable of infection with bacilli of human and 

 avian origin. But there is an observation to the effect that true tubercles 

 have been produced by inoculating bacilli of human origin into the peritoneal 

 cavity of frogs and carp (Moret). 



Bertarelli [is stated to have] succeeded in infecting snakes (Varanus varius) 

 by inoculating them under the skin with human tuberculous sputum but 

 failed with cultures of bacilli of avian origin. 



Moeller infected the blind worm [Anguis fragilis] with bacilli of human 

 origin (p. 334). 



Sorgo and Suess produced tuberculous lesions (caseating masses [at the 

 site of inoculation] and occasionally generalization) in two blind worms and 

 four snakes with bacilli of human origin, though many of their experiments 

 were negative. In blind worms the bacilli retain all the characteristics associ- 

 ated with the human tubercle bacillus but in snakes they [are said to ] undergo 

 a partial change and to develop some of the characteristics of bacilli of ichthic 

 origin. 



SECTION II. MORPHOLOGY. 

 1. Microscopical appearance. 



Human, avian and ichthic tubercle bacilli all have, in the main, the same 

 characteristics. In cultures they are small, very slender, generally non- 

 motile, rods. 



Ferran says that the tubercle bacillus is motile, but the conclusions arrived at 

 in his paper cannot all be accepted unreservedly. Arloing confirms Ferran's opinion. 

 By sub -cultivating a glycerin-potato culture on to glycerin- broth this observer 

 obtained motile bacilli. Schumowsky, in a similar experiment, also found motile 

 bacilli. Auclair [is said to have] succeeded in converting the tubercle bacillus into 

 a motile saprophyte, etc. 



In cultures on solid media the bacilli are arranged in long wavy coils some- 



u 



