Myxomatosis - Nongenetic Aspects of Resistance to Myxomatosis in Rabbits, Oryctolagus-Cuniculus

Abstract

Evidence is presented which suggests the transmission by bucks which have recovered from myxomatosis of a factor which confers on their offspring a non-genetic survival advantage against myxomatosis. This factor appears to be transmitted also to the offspring of does which have previously been mated to recovered bucks and then to non-recovered bucks. This advantage was greatest where a buck and his offspring had been exposed to the same virus strain. Fibroma immunization of bucks appears to remove this factor. It is suggested that much of the observed resistance in rabbit populations may be due to this non-genetic factor rather than to genetic resistance, and that resistance, at least in a domestic population selected for resistance, rose quickly initially and then very slowly.