MIYA, MARCUS AND PHELPS 



Temperature Treatment Mortality ratios at m days 



(grouped) 



210 C 



Noirmal 

 Immune 

 Zymosan 

 Endotoxin 



10/10 

 0/10 

 9/10 



10/10 



20 C 



Normal 

 Immune 

 Zymosan 

 Endotoxin 



10/10 

 0/10 

 9/10 



10/10 

 0/10 



Table X. Effect of acute cold stress (2^ C) on mortality of mice challenged intra- 

 peritoneally with 10 LD50* oi Staphylococcus aureus , strain Fritchie. Unacclimatized 

 animals immunized or treated and challenged at room temperature, then placed at 

 noted temperatures. *10 LD^q of S. aureus = 50 x 10^ organisms per mouse. 



acutely cold stressed are compared to acclimatized animals, the 

 latter do better than the former following challenge. It appears 

 that zymosan may benefit the challenged host in the animals kept 

 in groups under conditions of chronic cold stress, but not under 

 conditions of acute cold stress. This protective effect of zymosan is 

 not apparent in acclimatized animals caged singly. Again, some re- 

 servation in conclusions is warranted because of the low mortality 

 ratio of the mice kept at 21° C following the one LD^^ challenge dose. 



Effects of acute exposure following larger challenge dose. The 

 specifically or nonspecifically treated animals in this experiment 

 were maintained and challenged at room temperature. Following this, 

 the animals were immediately transferred to 2° Cor kept at 21° C as 

 controls. The challenge dose was increased by several orders of 

 magnitude over that in the previous experiments in order to obtain 

 more definitive results concerningtheefficacy of nonspecific versus 

 specific resistance to disease. The animals were caged in groups of 



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