ANNUAL REPORT, 1932 55 



their average annual egg production was 230 compared with an average production 

 of 208 eggs for the 10 individuals going broody. The broody line was made up 

 of 30 individuals. Three, or 10 per cent, were non-broody the first year. The 

 mean egg production of the 30 birds was 177. 



Deferred broodiness or the failure of the broody instinct to appear until after 

 the first laying year causes considerable difficulty in the selection of breeding 

 stock that is phenotypically broody or non-broody in the two lines. 



The study of the mode of inheritance of degrees of broodiness is being continued 

 as well as a study of the relation of broodiness to other characters affecting fe- 

 cundity. 



Breeding Poultry for Egg Production. (F. A. Hays and Ruby Sanborn.) 

 The mean annual egg production of the last generation of this experiment was 

 221 eggs. The mortality rate in the laying houses was 34 per cent without culling 

 and with all sisters of the families included. This flock was superior for intensity, 

 but there was a greater percentage of broody birds than in the previous flock. 



Egg size is being increased without the loss of high fecundity but more slowly 

 than would be necessary if high intensity were given less consideration. Hatching 

 records for 1932 were unsatisfactory because of a defective incubator. 



Statistical Study of Heredity in Rhode Island Reds. (F. A. Hays and 

 Ruby Sanborn.) Data have been prepared and published as follows: "Early 

 and late feathering in Rhode Island Reds," American Naturalist 66: 286-287, 1932; 

 "Types of intensity- in Rhode Island Reds," Bulletin 286; "The relation of feather 

 pigmentation to intensity of laying in Rhode Island Reds," Bulletin 288; "Heredi- 

 tary and environmental factors affecting variability in egg production," Bulletin 

 289; "Relation between body weight and age at sexual maturity in Rhode Island 

 Reds," Poultry Science 12:23-25, 1933; and "Relation of weight at sexual maturity 

 to annual egg production," Poultry Science 12:2vS-26, 1933. 



A Genetic Study of Rhode Island Red Color. (F. A. Hays.) The third 

 generation of crosses between exhibition and production-bred Rhode Island Reds 

 is now being carried in the laying houses. The Fi generation was intermediate 

 in plumage color, yet showed a rather w^ide range of color. The mean annual 

 egg record of this generation was 191. 



The F2 generation exhibited the extreme range in color of the parent stock. 

 The mean annual egg record of these birds was about 157. 



The ¥ i generation came from mating F? x F2 and from mating F2 to parental 

 stock. There is very definite segregation both of color pattern and of fecundity 

 traits. 



Determination of Genetic Laws Governing Results of Inbreeding. 



(F. A. Hays.) The first generation of daughters hatched in 1929 from sire on 

 daughter matings averaged 180 eggs with a mean age at first egg of 216 days. 

 The second generation from half-brother x sister matings had an average annual 

 egg record of 190 with a mean age at sexual maturity of 192 days. A third genera- 

 tion of 24 birds hatched in 1931 had a mean annual production of 196 eggs and a 

 mean age at first egg of 213 days. None of the third generation daughters in 

 one of the three inbred lines could meet the standard for breeders and this line 

 became extinct with this generation. 



The value of inbred males mated to unrelated females to test prepotency is now 

 being studied. 



Factors Affecting Egg Weight and Shell Character in Domestic Fowl. 



(F. A. Hays.) The fifth generation of birds was hatched in 1932. The criterion 



