204 DAIRY CATTLE AND MILK PRODUCTION 



or with a ration of grain that supplies ample material for 

 growth, such as wheat, bran, or oats. 



Age to Breed. The age at which cows should come into 

 milk depends somewhat on the breed and the maturity of 

 the animal. The larger breeds, as the Holstein and Brown 

 Swiss, as a rule should not calve much before thirty months. 

 The more rapidly developing Jersey is, as a rule, sufficiently 

 mature at two years. Other breeds rank in between these 

 extremes. The proper age to breed depends somewhat on 

 the size and development of the heifer. Heavy feeding of 

 grain results in an animal large for its age and early sexual 

 maturity. 



Some breeders prefer to have the first calf dropped at 

 rather a young age, claiming in this way to fix a habit of 

 milk production in the young animal, and at the same time 

 securing financial returns as early as possible. A common 

 practice among these breeders is to allow about eighteen or 

 twenty months between the first and second calves. In 

 this way a long milking period is developed, and the cow 

 has time to grow before the birth of the second calf. 



It is a severe strain on the heifer to develop the fetus. 

 Our investigations show that during the last three months 

 of pregnancy a heifer, even when fed a liberal ration, does 

 not add to her own body. The increase in weight shown is 

 all found to be in the fetus. After the calf is born, the 

 heifer weighs, as a rule, no more than she did three months 

 previously. 



Breeding too young undoubtedly results in small cows. 

 It is impossible for a young cow to digest and assimilate a 

 sufficient amount of feed to produce milk and growth at 

 the same time. The production of milk, on account of its 



