6 Diseases of Poultry 



of heredity, the first selection of birds for the breeding pen 

 should be made on the basis of their general constitutional 

 vigor. No bird which shows signs of weakness in this funda- 

 mental regard should ever be used as a breeder under any 

 circumstances. If such a bird is used the breeder will 

 eventually have to pay the penalty. 



The external, visible evidences of a sound constitution 

 and a possession of abundant vitality and vigor are numerous. 

 In the first place the bird of sound constitution will be in 

 perfect health. Perhaps its most striking characteristic will 

 be an independence of disposition and demeanor. By this 

 is not necessarily meant aggressiveness. The bird, whether 

 male or female, which is forever picking quarrels with its 

 fellows is by no means always the bird of greatest vigor. 

 Strange as it may seem a bird may indeed be very far from 

 a mollycoddle and yet have a peaceable disposition. It 

 may be taken as an unfailing characteristic of birds of high 

 constitutional vigor, however, that they are able to take 

 care of themselves and may not be imposed upon, or bullied 

 by their fellows, with impunity. While they may not pick 

 a quarrel, they are abundantly able to make a forceful 

 presentation of the merits of their end of any debate which 

 another bird may choose to enter upon with them. In 

 other words they have, as has been said, an independence 

 of disposition ; an ability, reaching to the limits of gallina- 

 ceous capacity, to meet all situations which may arise in 

 the day's work of a fowl, whether food getting, fighting, 

 rearing yoimg, or what not. 



The bird of high constitutional vigor will have a thrifty 

 appearance, with a bright eye, and clean, well-kept plumage. 

 The head will be broad and relatively short, giving in its 

 appearance plain indication of strength. It will show 

 nothing of the long-drawn-out, sickly, crow-like appearance 

 of the head which is all too common amongst the inhabitants 



