Constitutional Vigor ijsr Poultry Breeding. 



615 



(9) Brooding and rearing chickens under crowded conditions with a 

 general violation of the principles of sanitation. However important it 

 may be that mature fowls be kept in healthful environment, it is 

 equally important that the chickens be raised naturally and rapidly 

 on the best rations and under free-range conditions. Too rapid forcing 

 on rich, easily assimilated food, with lack of exercise, results in leg weak- 

 ness and faulty digestion. Feeding too large a proportion of coarse 

 feed containing much fibre, making it slow of assimilation, results in 

 stunted growth and the trouble known as " long wings." 



Fig. 8. — An extreme case of low vitality resulting in slow feathering and irregular 

 development. Notice also the "crow-head." 



(10) Failure to select breeding stock of recognized superior physical 

 vigor. The most vigorous breeding stock is necessary if we are to main- 

 tain or increase the physical vigor of our fowls. This selection is possible 

 if the breeder has a clear understanding of the physical differences be- 

 tween constitutionally strong and constitutionally weak fowls. Such 

 differences exist and can be quickly recognized by any one who will 

 take the trouble to study the various types of fowls. 



