CHAPTER V. 



BUILDING UP A DAIRY HERD. 



I. PRINCIPLES INVOLVED. 

 II. STARTING THE HERD. 

 III. BREEDING UP THE HERD. 



I. PRINCIPLES INVOLVED. 



Underlying Law. The success in building up a dairy 

 herd depends to a great extent upon one's ability to select 

 individuals with reference to the points considered in the 

 preceding two chapters; that is, the ability to make a 

 judicious selection of both males and females. To em- 

 phasize more fully the importance of rigid selection it 

 should be remembered that all selection is based upon 

 the law that "like produces like," or that the offspring 

 will be like the parents. The essence of this law is that 

 good milkers will produce good milkers and poor milkers^ 

 will produce poor milkers. 



The uniformity with which this law operates is depend- 

 ent upon three things : ( i ) purity of breeding ; (2) close- 

 ness of blood relationship; and (3) similarity of parents. 



Purity of Breeding. The purer the breeding the 

 greater the certainty with which animals will transmit 

 their own characteristics to their offspring. See p. 14. 



Closeness of Blood Relationship. The characters of 

 parents of the same strain will reappear in the progeny 

 with greater regularity than those of parents of different 

 strains in the same breed. This fact is recognized in 

 in-and-in breeding, which is an attempt to secure and 



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