The Possible Rôle of Inheritance in the Quantitative Character of a Coccidian Infection of the Rat

Abstract

The writers (1932) have previously reported on the surprisingly great individual variability in susceptibility to infection with Eimeria miyairii which they encountered among white rats taken at random. It was learned in the study that young rats of from 65 to 149 g. in weight would eliminate from 14 to 169 million oocysts during immunisation produced by inoculation per os with 1500 sporulated oocysts daily over a period of 5 days. The question naturally arises whether different strains of the host exhibit differences in susceptibility similar to those noted in individuals.