CONTENTS. 



Introduction ...... 



The working hypothesis .... 



Plan of procedure ..... 



The foundation stocks . . . 



Basis of selection of breeding females 



Basis of selection of breeding males 



Continued use of breeders on the basis of the performance of 

 offspring ........ 



Points in management that affect the results 



Seasons at which increased production is most desirable 

 Results secured ..... 



Changes in mean winter egg production 



Changes in mean annual production . 



Changes in daily winter production . 



Changes in age at which first egg is laid 



Changes in length of the initial cycle and its complement, the winter 



Changes in amount of broodiness 



Changes in date of last egg 



Changes in rate (intensity) of production 



Changes in seasonal distribution of production 



Changes in variability 



Influence of changes in sanitary methods 

 Recommendations ..... 



Summary ...... 



Literature cited ..... 



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