THE BREEDING OF CHICKENS 



117 



The actual inlp^o^'cmcnt with regard to unifdriiiity runs 

 ratlier in advance of the percentages sliown in tlie eliart 

 after the first cross, as sliowii liy Lippinccitt' and ilhistraled 

 in iMgures -Id to 4*1. l'"ui-thernj()re, standard-hred males 

 are prejjotent over mongrel females in most characteristics. 

 Prepotency is the breeders term for the superior power 

 which one i)arent has over the other in determining the char- 

 acter of the offspring. It increases with (1) standard breed- 

 ing, (2) line lireeding, and (3) long-continued breeding, 

 because each of these tend auttunatically to produce purity 

 in a given character. 



Fig. 50 



A hen carrying seven-eighths Single Comb Wliifr Lcglicirn ijloo<l wliose 

 egg record is 303 in twelve mouths and 505 fur tncnty-four months. 

 (Courtesy of Oregon Agricultural Experiment Station.) 



If only individuals of the highest constitutional \igor are 

 used, improvement will l)e found still more satisfactory if 

 the pure-bred males used from year to year are members 

 of the same family as well as members of the same breed. 

 The reasons for this are discussed under "line breeding." 



' Kansas Bulletin No. 223. 



