44 



A STUDY OF FARM ANIMALS 



Relative intensity of blood lines and approximately relative influence 

 of different generations and individuals for ten generations backwards. 



The statement set forth by this table shows how little 

 influence is derived from one individual in the ancestry ten 

 generations back. In fact, until recently a number of our 

 live-stock associations promoting and registering pure-bred 

 animals would accept for registry individuals that five gen- 

 erations back showed impure blood. Yet the value of blood 

 lines depends also on the character of the breeding. If the 

 ancestry contains the names of animals of distinction within 

 the same family lines, then it will mean much more to the 

 breeder who understands pedigrees than it will if the inherit- 

 ance shows no family names of value. 



The merit value of a pedigree is shown in the character 

 of the records made by the different animals composing it. 

 This phase of the pedigree receives very careful attention 

 from the thoughtful breeder. Some of the most interesting 

 examples of constructive breeding that have taken place in 

 America in recent years, are clearly brought out in pedigrees 

 where record of performance was ever kept in mind by the 

 breeder. The following pedigree of Sophie's Bertha, one of 

 the great Jersey cows of America, is an interesting illustra- 

 tion of sucli constructive breeding. 



