BULLETi:^ IsTo. 211 



DEPARTMENT OF POULTRY HUSBANDRY. 



CHANGES IN EGG PRODUCTION IN THE 

 STATION FLOCK. 



BY H. D. GOODALE AND RUBY SANBORN. 



Introduction. 



For the past eight years the work of the Massachusetts Agricultural 

 Experiment Station with poultry has centered about the problem of 

 breeding better layers. A certain measure of success has been reached. 

 The present paper is a descriptive history of the work. The theory that 

 is under test, the plan of procedure, the results secured to date, with 

 such comment as seems to be required to prevent misinterpretation of 

 the data, with such suggestions as can be offered to the breeder, are 

 presented. 



The Working Hypothesis. 



The studies were begun in December, 1912. It was then supposed 

 that the inheritance of fecundity was a simple two-factor Mendelian 

 matter, but it was not long before it gradually became clear that, with 

 Rhode Island Reds, the egg record made by a bird was the result of the 

 combined action of a number of inheritable characteristics. 



Simplifjdng matters as much as possible, five main characteristics may 

 be recognized, namelj^: — • 



1. Maturity. 



2. Rate (intensity). 



3. Broodiness. 



4. Point at which production ceases (persistency). 



5. Winter pause. 



Each component is very variable. Resulting egg records from combina- 

 tions of these five variable characteristics are illustrated in Figs. 1 and 2. 

 In Fig. 1 are used the two extremes only of each of the five components, 

 which make 32 possible combinations, each illustrated by an actual 



