THE DEVELOPMENT OF THE DAIRY HEIFER 205 



relation to reproduction, is a dominant function, and will 

 not be materially checked to allow growth to continue. 

 For this reason it can hardly be expected that a heifer 

 calving young and immature in size will develop into a cow 

 of normal size if she calves regularly each year afterwards. 



The cow that has calved early as a rule shows a more 

 pronounced feminine characteristic, and is finer in the bone, 

 than the one that has calved at a later age. 



The Development of the Dairy Heifer. As already 

 pointed out, one of the most important factors influencing 

 economical milk production is the individuality of the cows 

 used. It has been suggested that this probably is depend- 

 ent mostly upon inheritance. Still the question arises, and 

 is one of great importance as to the effect of the manner of 

 raising the heifer upon the dairy characteristic when mature. 

 In other words, is a superior or inferior cow born or made? 



In 1906, with the view of getting data upon which to plan 

 an investigation along this line, the Missouri Experiment 

 Station sent a list of questions to the leading breeders of 

 dairy cattle in the United States, to learn their opinion upon 

 these factors that may influence the development of dairy 

 heifers. Replies were received from 301 breeders, repre- 

 senting an experience of breeding 150,000 animals. The 

 widest possible divergence of opinion was found respecting 

 some of the points covered. A series of investigations was 

 then undertaken to gather more accurate data under ex- 

 perimental conditions. According to the plan, one group, 

 numbering 20 animals, was to be fed on whole milk, and to 

 receive all the grain they would consume from birth until 

 they came in milk. Another 20 were to be raised on skim 

 milk and alfalfa or clover hay without receiving any grain 



