Effects of limb disability on lousiness in mice. IV Evidence of genetic factors in susceptibility of Polyplax serrata

When amputee mice were infested with lice (Polyplax serrata) Burm. and kept individually, most of them rapidly developed comparable louse populations. However, certain mice appeared to resist development of louse populations.
Several strains of mice were tested and a wide range in susceptibility to infestation with lice was found. The greatest number of lice developed on C57BL/6JN mice and the smallest number on mice of the CFW strain. Those strains of mice that supported the largest number of lice had the greatest mortality.

The cross breeding of resistant and susceptible strains of mice revealed evidence of a genetic mechanism. From these crosses it was established that the sex of the resistant parent may be a genetic factor influencing the reaction of the offspring to louse infestation. Coat color of the mice appeared to influence louse infestations, but these studies were inconclusive.

Attempts by selective breeding to enhance the natural resistance exhibited by certain mice were not successful. Nevertheless, progeny of resistant parents were as resistant as the parents.