Studies in Forage Poisoning V. 71 



antitoxic serum. Kempner, Forssinan, Wasserman 25 and 

 Leiichs-' 1 have reported 011 the specific antitoxic quality of serum 

 from small and large animals with various strains of B. bot- 

 uliniis. Kempner succeeded in producing an efficacious anti- 

 toxic serum from rabbits, and Wasserman obtained an anti- 

 toxic goat serum which protected guinea pigs against many 

 times the lethal dose of toxin. Leuchs mentions, in one instance, 

 the non-protective quality of an antitoxic serum against a toxin 

 of different strain, suggesting that antitoxic serum might prove 

 more efficient in its general application if produced from toxin 

 of polyvalent origin. Many other strains, however, proved ca- 

 pable of producing an efficient antitoxic serum against hetero- 

 geneous strains of remote origin. 



In the preparation of antitoxic serum at this laboratory 

 rabbits and guinea pigs were not employed, but for preliminary 

 trials, a goat, a sheep and a cow were selected. After repeated 

 subcutaneous injections of toxin (unfiltered broth cultures), it 

 was found that these animals yielded an antitoxic serum which 

 would protect guinea pigs and horses against many times the 

 fatal dose of homologous toxin. In several instances horses were 

 apparently protected by the subcutaneous administration of the 

 antitoxic serum against 2 to 5 cc. unfiltered broth culture of 

 B. botulinus administered by the mouth and subcutaneously. 



In arriving at a suitable test for potency the fatal dose of 

 toxin for guinea pigs was used as a basis. Death consistently 

 followed the administration of 0.05 cc. toxin by the mouth, 

 without reference to size (avoiding pregnant pigs), in 24 to 

 50 hours, and in preliminary tests 0.05 cc: of toxin was employed 

 against varying amounts of serum. Later the amount of toxin 

 was increased to 0.1 cc. and in some instances to 0.25 cc., in 

 coiijiinction with varying amounts of serum. The amount of 

 serum employed varied from 0.5 to 2 cc. ; in some instances pigs 

 received 2.5 cc., 3 cc. and 3.5 cc. of serum respectively. In 

 preliminary trials 2 cc. of antitoxin administered intraperitone- 

 ally afforded protection, while pigs receiving 0.5 cc. seemed 

 equally well protected. The following charts illustrate the effi- 



25 Handb. d. path. Mikroogr., IV, p. 934 (cited by van Ermengem). 

 26 Handb. d. path. Mikroog., IV, pp. 939-945. 



