The Reaction of Standard Breeds of Rabbits To

For several years a colony of standard bred rabbits has been maintained by this laboratory as the basis for the study of problems in constitution. The foundation stock for the colony was built up from pedigreed and registered animals purchased in this country and abroad. The breeds represented were chosen mainly on the basis of physical conformation, and the stock includes a full range of contrasting types from the small Polish to the Giant Flemish, and the cobby Dutch to the racy Belgian. Representative color varieties and coat characters are also included? One of the purposes for which this colony was organized was to provide material of known quality for the study of relations between constitution and susceptibility to disease (1). As an approach to these problems, experiments were carried out with pure bred rabbits of various lines to determine, on the one hand, whether such differences as are represented by breed characters may be associated with distinctive differences in the reaction to disease-producing agents, and on the other, for the purpose of selecting the most suitable material for a more detailed study of any relations which might be found. The present report is concerned with observations on the response of different breeds of rabbits to one of the agents employed, namely, Tr. pallidum.