The Improvement of the Flock 155 



tor, they are likely to hold in common the charac- 

 teristics of that common ancestor. These common 

 characters may be good ones or poor, or they may 

 comprise both. The principle of the matter has been 

 tersely stated in these words: "The injury from 

 line-breeding comes not because of kinship in blood, 

 but because of kinship in defect." The concentra- 

 tion of the blood of a single animal that is the 

 result of line-breeding serves to concentrate and 

 perpetuate the characters of that animal. The 

 result is not from the fact that the parents are 

 related. No new character or qualities are brought 

 about, but simply extra likelihood of resemblance 

 to the animal whose blood is concentrated. Some 

 of the successful breeders who do not favor the 

 practice of concentrating the blood prefer to con- 

 centrate the type. They use a succession of sires 

 that are no blood relation but which are of the same 

 type and individual qualities. When it can be done, 

 concentration of type serves as well to secure the 

 uniformity and prepotency that results from in- 

 breeding or line-breeding. It is doubtful, however, 

 whether the eflfect is quite so pronounced when a num- 

 ber of similar animals are used as when the same indi- 

 vidual appears a number of times in the pedigree. 



Many of the early improvers and founders of the 

 breeds worked under conditions that afforded no 

 field for the selection for similarity of type. To 

 concentrate type, they were forced to concentrate 



