118 



GENETIC STOCKS AND BREEDING METHODS 



way to becoming established strains. The stocks bearing marker genes maintained by 

 Dr. C. Cohen are of considerable value for certain immunogenetic work, and it is likely 

 that more populations of this kind will be developed in the future. There is no doubt 

 that a vast reservoir of genetic material exists in the many stocks maintained by fanciers, 

 but unfortunately they are not readily identifiable at this time. It would be most 

 desirable if genetic material for this species, comparable to the murine material, could 

 be collected in one or more places and properly maintained for mammalian genetic 

 research. 



The standardization of strains and stocks of rabbits has not been done in a manner 

 similar to mice, but the adoption of the same rules for designating and defining strains 

 and substrains and the promulgation of symbols is desirable. However, it may be 

 advisable to amend the rules so that inbred strains can be defined in terms of an 

 inbreeding coefficient (F) in addition to the definition based on matings of brother x 



Table 38f 



Strains of Rabbits in Development 



The amount of inbreeding is expressed either as F generations of brother x sister matings 

 or by the inbreeding coefficient (F). 



Name or 

 Symbol 



Synonym(s) 



Remarks 



A inbr: F 19 . origin: M. Lurie, 1932, from a heterogeneous stock 



obtained from E. L. Stubbs, University of Michigan, b x s matings 

 since the start of inbreeding, charac: resistance to tuberculosis 

 variable (highly resistant up to F 8 ), low fertility, many die of impaction 

 of the large intestine (perhaps faulty peristalsis?), maintained 

 by: Lu. 



AC inbr: F = 36%. origin: P. Sawin from Rockefeller Institute Dutch 



stock, charac: black, recessive white marking, aa or A-E d E d du-, 

 occasionally segregating for y and ac, mature female body weight 

 2200 g. maintained by: Sa. 



ACEP inbr: F = 70%. origin: P. Sawin from Rockefeller Institute Dutch 



stock, charac: aa or A-E d E d du-epep (black, recessive white marking, 

 audiogenic seizures), occasionally segregating for v and agonadia, 

 mature female body weight 2400 g. maintained by : Sa. 



AD inbr: F 8 . origin: M. Lurie from a Strain A x Strain D cross (Strain 



D is now extinct), charac: intermediate resistance to tuberculosis, 

 medium fertility, dutch color, maintained by: Lu. 



AX inbr: F — 36%. origin: P. Sawin from outcross of chinchilla Race V 



to Races III and X. charac: Ach d ww, Axas forced heterozygosis, 

 occasionally segregating for du, ep, bu, ch m , c, mature female body 

 weight 3500 g. maintained by: Sa. 



B inbr: F 10 . origin: C. Cohen from Rockefeller Institute Dutch stock, 



separated from Strain Y and Strain R at F 2 , to C. K. Chai at F 7 . 

 charac: segregating for yellow fat y, and angora (1), albino, mature 

 body weight 2000 g. maintained by: Ci. 



f A list of abbreviations follows table 39. 



