502 Tuberculosis. 



emulsion or homogeneous liquid cultures). Baumgarten had then already shoxvu 

 that a single subcutaneous vaccination with human tuljercle bacilli increased the 

 resistance of cattle to a marked degree. Hutyra had also shown that cattle thus 

 vaccinated would be protected for a time against infection by intravenous injection 

 of 0.04 gm. bovine tubercle bacilli but that such immunity diminished noticeably 

 after six months. According to Arloing's experiences subcutaneous vaccination 

 does not produce as high a degree of resistance as the intravenous administration 

 of vaccine. 



2. Friodmann recommended a strain of tubercle bacilli for vaccination of 

 cattle which he had cultivated from a turtle, and successfully protected rabbits 

 against bovine bacilli. After Libbertz and Riippel and also Orth failed to con- 

 lirm the favoralde results claimed by Friedmanu, "Weber & Titze showed that while 

 the repeated intravenous administration of large masses of bacilli derived from 

 cold-blooded animals, or of acid-fast grass bacilli, no doubt might increase the 

 resistance of cattle to infection with bovine bacilli to a slight extent, the effect 

 is so slight that the practical application of the method is of questionable value. 



.^. According to Behring as well as Calmette & Guerin it is possible to 

 immunize cattle against intestinal infection by the administration of a small 

 (|uantity of bovine bacilli per os. Eoux & Yallee obtained good results by two 

 administrations, per os, to young calves, at intervals of three months, of 0.20 gm. 

 doses of equine tubercle bacilli or of viruient bovine bacilli. Animals thus treated 

 were found, in some cases to possess greater resistance to subsequent infection than 

 those imnuini^ed by the intravenous method. The advantage of this method of 

 immunization is claimed to be that bacilli thus administered are completely absorbed 

 in a period not longer than 7 months. On the other hand, alimentary infection 

 occurring during or immediately preceding the period of preventive treatment will 

 give rise to a progressive tuberculous condition. Even Vallee himself admits that 

 attenuated human tvbercle bacilli, the alimentary administration of which gives 

 similar results, i.Te perhaps more suitable for this purpose. 



4. Arloing uses homogenized cultures of human or bovine bacilli grown on 

 6% glycerin bouillon for the immunization of cattle. These cultures do not 

 produce microscopic tubercules in small experimental animals or in calves but only 

 microscopic changes of the Yersin type. The cultures are administered intraven- 

 ously, subcutaneously or per os. According to the first method young calves receive 

 0..5 cc. for the tirst dose; two months later 1.5 cc. of a culture one month old is 

 injected into the jugular vein (older animals receive 1.0 to 1.5 cc). In the 

 subcutaneous method both the first and second applications are made subcutane- 

 ously (2 cc. of culture being injected each time in the side of the neck or in the 

 flank). According to the third method the first dose consists of 15 cc. and the 

 second dose, two months later, of 20 cc. of culture carefully injected into the 

 mouth so that the animal will swallow the same. In all three methods it is neces- 

 sary to follow up the treatment with annual subcutaneous injections of 2.0 cc. of 

 culture in order to maintain an effective degree of immunity. These treatments 

 always result in tuberculin-hypersensitiveness which, however, gradually leads in 

 about six or eight months to the opposite condition, that is a tolerance. Moderate 

 fever of short duration follows the intravenous as well as the subcutaneous admin- 

 istration of the virus and in the latter method a local tumor with friable cheesy 

 contents develops at the point of injection. This usually disappears in the course 

 of several months. 



Results of the vaccination of 60 cattle ranging in age from 4 to 12 months, 

 with 30 control animals in the experiment, were only partly successful. After 

 exposure to infection only about 50% of the vaccinated animals remained healthy; 

 of the infected animals some were only slightly affected but others were extensively 

 diseased. Nevertheless the results as a whole were in favor of immunization. The 

 fact that the cultures used were harmless for cattle, as well as for monkeys, also, 

 deserves favorable consideration of the method. The intravenous method gave the 

 1 est results, the ingestion method came second and the subcutaneous method last in 

 efficacy. 



5. Vallee immunized horses by intravenous injections of successively increas- 

 ing doses of, first, equine bacilli avirulent for guinea pigs, which then were followed 

 liy human tubercle bacilli slightly virulent for guinea pigs. The injections pro- 

 iluced no tuberculous processes whatever. After treatment for one or two years the 

 serum of these horses, though possessing only slight agglutinating power, con- 

 tained protective substances that could be demonstrated by the complement fixation 

 method, and which in doses of 100 to 200 cc. protected young cattle against experi- 



