58 Milk and Its Products 



mal, carefully kept, should retain his breeding powers 

 up to eight or nine years of age, or even beyond. 



Grading .up the herd. The successful and pro- 

 gressive dairyman will not only give his best efforts 

 toward securing a herd that will make a satisfactory 

 production, but will look to the future, and secure 

 still further improvement by breeding from his herd 

 succeeding generations that shall be even larger pro- 

 ducers than their ancestors. Such a dairyman may, 

 if he chooses, secure as the foundation herd pure-bred 

 animals that may be depended upon to transmit their 

 qualities to their descendants. But with even the 

 highest-bred animals there will be the necessity for 

 selection, if the original standards of production are 

 to be maintained, to. say nothing of being increased. 

 On the other hand, the large majority of dairymen 

 seeking to improve their herds must depend, more or 

 less, upon the individual animals they have already 

 on hand as the basis from which to start the im- 

 provement. In either case, careful selection must be 

 practiced, and a knowledge of at least the elementary 

 principles of selection is 'necessary for progress along 

 this line. It is proposed, then, briefly to indicate the 

 lines along which an attempt to breed up, or improve, 

 a herd of common, native or mixed cattle is most 

 likely to prove successful. 



In the improvement of a herd of cows it has been 

 very common to recommend that the practice should 

 be to use a pure-bred bull, and to raise the heifer 

 calves from the best cows in the herd. Whether or 

 not this practice is correct will depend, to a great 



