TRANSPLANTATION AND INDIVIDUALITY DIFFERENTIALS IN INBRED STRAINS OF RATS

Abstract

In the course of > 100 consecutive brother-sister matings in family A. and of somewhat < 100 brother-sister matings in family B of King''s inbred albino rats, a gradual increase in the homozygous condition of the inbred families has taken place, as indicated by the lessened severity of the reactions of the hosts against the individuality differentials of various members of these families. However, the advance was slight in the course of the first 67 generations of brother-sister matings; it was greater between the 67th and 102d generations; but even at the latter point a completely homozygous condition in the inbred family A had not yet been attained. These results were obtained in testing the interaction of the individuality differentials by transplantation of litter mates, of members of different litters, as well as of hybrids of these inbred strains.