The Effect of Environmental Temperature on the Reaction of Mice to Tetanus Toxin

Abstract

In two consecutive summer weeks, pronounced differences in survival time were noted for mice subjected to identical doses of tetanus toxin. Room temperatures at the time of the two observations were 25 C and 35 C, respectively (Experiments 2 and 3, Table IV). Survival times are ordinarily reproducible when the same dose is used. One possible explanation of the observed differences was the environmental temperature. Variation in inherent susceptibility between two lots of mice rarely causes such differences, as judged by experience with mice from the same laboratory stock (4), or from different laboratories in various parts of the world (6). The effect of environmental temperature on resistance to infection has been studied experimentally through temporary chilling (2) of animals subjected to fixed doses of a pathogenic agent (5). Momentary exposure of infected animals to extreme variations in temperature is seemingly less comparable to natural conditions than where experimental animals are maintained at uniform raised or lowered temperatures that are consistent with the survival of normal animals.