1916.] PUBLIC DOCUMENT — No. 31. 49a 



Third. — The prime factor in securing a high annual egg pro- 

 duction, besides early maturity, is nonbroodiness. The addition 

 of early maturity and nonbroodiness to the station strain should 

 result in a big increase in egg production. 



Work along our main lines has proceeded as usual. The 

 accumulation and handling of the necessary data require a large 

 amount of tedious routine work. In all probability it will be 

 necessary to continue this work for several years, although it is 

 hoped that certain phases can be brought to a close sooner. 



A considerable number of nonbroody Rhode Island Red hens 

 is now on hand. There is also a large number of pullets bred 

 for nonbroodiness in the laying houses. A study of the data on 

 broodiness shows that whenever a hen goes broody her egg pro- 

 duction falls off about 40 per cent. As each hen, on an average, 

 goes broody about five times in her pullet year, it means that if 

 broodiness can be eliminated an increase in annual egg pro- 

 duction of about 33f per cent, can be secured. On a flock 

 average of 120 eggs per annum it means 40 eggs, or from 80 to 

 100 cents, since these additional eggs are produced during the 

 summer and fall. 



The number of nonbroody hens on hand enables us to proceed 

 to the next phase of the work, viz., the testing of males belong- 

 ing to this line. As many males as possible will be tested the 

 coming season. The results of the test will not be completely 

 known until the fall of 1917, since the pullets must make at 

 least a year's record before they can be considered nonbroody. 



An examination of the data on the age of pullets when the 

 first egg is laid shows a surprising amount of variability. A 

 number of pullets hatched the same day and kept in one flock 

 throughout the test may range from 195 days of age to over 

 300 when the first egg is dropped. On the other hand, the 

 correlation between the length of time the bird has been laying 

 and the number of eggs produced prior to March 1 is fairly 

 high, r = -1- .8612 + .0132. 



The studies on broodiness emphasize the need for one or two 

 pens where the environment can be controlled. The height of 

 the broody season comes during the warm raonths, but it is not 

 clear whether the large amount of broodiness is due to the tem- 

 perature alone or to cyclic changes in the birds. If the former, 



