150 Farm Poultry 



bation is one that always gives breeders more or 

 less concern. Some breeders are more successful 

 than others in securing, fertile eggs, and, appar- 

 ently, all breeders are more successful during some 

 seasons than others. Some breeds of fowls are 

 noted for producing fertile eggs, while others are 

 generally recognized as inferior in this respect. 

 The freedom given the fowls of a flock, the vigor 

 of the individuals, and the number of males, very 

 largely ^determine the fertility. Pullets' eggs are 

 generally not selected for hatching. It is thought 

 that they are not so likely to be fertile, and will 

 not produce so strong and vigorous chickens as 

 hens' eggs. 



Those who have had experience in operating 

 incubators know that not all fertile eggs will hatch. 

 There seem to be all grades of fertility, from the egg 

 having a vigorous germ that will produce a strong, 

 healthy chicken, to that having a weak germ and 

 is practically an infertile egg. As the two extremes 

 are united by various intermediate grades, it is 

 impossible to draw a definite line of separation 

 which shall divide the fertile from the infertile ones. 



Fresh eggs are to be preferred for hatching, 

 although good hatches from eggs that were kept 

 several weeks are reported. Eggs are sometimes 

 sent long distances and still retain their vitality 

 sufficiently to produce a good number of strong 

 chicks. The following is quoted from an experi- 



