lOO MAINE AGRICULTURAL EXPERIMENT STATION. I9IO. 



WINTER EGG PRODUCTION IN THE HYBRID AND PURE BRED 



PULLETS. 



The egg production of these hybrid birds in comparison with 

 the pure bred stock is a matter of a great deal of interest. The 

 two breeds crossed differ very markedly in their innate pro- 

 ductive capacities. One has good egg production and the other 

 poor egg production as definite and fixed breed characters. In 

 the hybrids is afforded an opportunity to test the question of 

 whether egg production is inherited as a definitely segregable 

 character. To settle this question is a very important matter 

 in connection with the whole problem of breeding for egg pro- 

 duction. 



In order to get results which shall be in any way reliable in 

 a study of this kind certain conditions have been found in the 

 long experience at this Station in the study of egg production 

 to be of fundamental significance. The most important of these 

 are: 



(i) A relatively large number of birds must be trap nested 

 to secure reliable results. Comparisons of egg production based 

 on returns from 5 to 10 birds can only lead to indefinite and 

 uncertain results. Egg production is a character which shows 

 wide fluctuating variability. This condition demands reason- 

 ably large numbers of birds, in order to determine the variation 

 constants. 



(2) The material must be biologically homogeneous. Lump- 

 ing together the egg production of several small flocks may give 

 entirely fallacious results. 



(3) Environmental conditions must be the same for all birds 

 and average age must be the same. 



(4) To get reliable results regarding the inheritance of pro- 

 ductivity, experience here has shown most clearly that the envi- 

 ronmental conditions (housing, feed, management, etc.) must 

 be favorable to good egg production. In other words, some- 

 thing more than simple uniformity of environment is demanded 

 to get reliable results. Only under favorable conditions can 

 the birds bring to full expression their innate laying capacities, 

 whatever they may be. Under unfavorable conditions the inter- 

 pretation of results must always be uncertain, because it is im- 

 possible to say how far an observed result is due to innate and 

 how far to environmental factors. In this same connection it 



