272 



MASS. EXPERIMENT STATION BULLETIN 258 



A comparison of Table 8 with Table 5 at once emphasizes the superior char- 

 acter of the 1924 dams in egg size. In 1923 only two dams laid a standard weight 

 egg of 56.7 grams, while in 1924 four of the five check dams laid standard weight 

 eggs and four of the seven inbred dams laid eggs of standard weight. 



Hatchability ran higher in the inbred groups than in the checks. In fact, 

 only one check hen reached medium hatchability. Egg weight and chick weight 

 were again closely correlated. Chick mortality rates to September first were 

 very sUghtly higher in the inbred groups than in the checks. These data do not 

 indicate an important relationship between the percentage of fertile eggs hatched 

 and the percentage of range mortaUty. 



The mean number of offspring per mother did not differ greatly in the check 

 group and the inbred group for the mothers actually producing chicks, but there 

 were more unsuccessful matings among the checks than among the inbreds. 



A comparison of the weight records of offspring for one year shows that the 

 check birds were decidedly heavier than the inbreds from hatching time on. A 

 significant difference in the weight of males and females did not appear until four 

 weeks of age. Table 8 also shows that the mean weight of pullets was greater at 

 first egg than at the age of one year. This difference was not due to a loss of 

 weight during the year but to the fact that the mortahty rate in the laying houses 

 was greater among the heavy birds both in the check and in the inbred groups. 



Mortality rates for pullets in the laying houses were decidedly high. Several 

 of the families were completely obhterated. The gross mortaUty rate for the 

 inbreds was significantly greater than for the checks. These losses were aug- 

 mented by a severe epidemic of pox and roup attacking all the flock. 



Table 9. — Record of All Surviving Daughters from the 1924 Matings 



C 7957 . 



C 7718 



C 6127 



C 6192 . 



Check Group 1 



I E 208 1 186 I 6.45 | 56 



Check Croup 3 



IE 220 1 321 I 6.90 | 



Inbred Group 4 



I 1-4 1 



E 654 

 E 2132 



315 

 192 



5.85 

 5.12 



1.8 



2.4 



I 





 30 



306 



131 

 171 



Inbred Group 5 



168 



239 



170 

 134 



225 

 203 

 213 



Check Group 2 and Inbred Group 6 had no complete records. 



Table 9 shows that the three check groups of 1924 were practical failures from 

 the standpoint of reproduction. Only two davighters from the three check groups 

 aurvived to complete the laying year. The character of the parents used in 1924 



