32 FORM, FUNCTION, AND CAPACITY 



food products to the finished product is vitally connected 

 with the circulatory system, as the blood carries the elements 

 of milk elaboration. The stimulation received, therefore, 

 from the blood supply measures quite accurately the capacity 

 of an animal and the profits which will be obtained therefrom. 

 Although the evidence of a strong blood supply is especially 

 significant in the dairy animal, it is of no less importance in 

 the animal which is used for draft, light harness or saddle 

 work, or in those animals which are used directly for food- 

 producing purposes. The blood supply and the energy which 

 it carries in the way of assimilated food materials is all 

 manifested in some specific way no matter what the character 

 of work to be performed. The amount and continuity of 

 work is thus measured by the circulatory system which 

 carries the elements or products of energy to the specific 

 place of use. 



Mammary Organs. The mammary organs or the mam- 

 mary glands are of special significance in the dairy cow 

 wherein stimulation of milk-giving capacity has been in- 

 creased by breeding, selection, and by the administration 

 of proper food materials. Although it is in the dairy animal 

 that the most vital consideration is usually given to the 

 mammary organs, they must, of necessity, become a con- 

 sideration, either in the meat-giving or work-producing 

 animals. The difference in the degree of development in 

 these three broad classes of animals is not as great as might 

 be first suspected. The dairy cow is measured by her milk- 

 giving capacity, the meat-producing animals by the amount 

 and quality of the meat products which they elaborate, and 

 the work-producing animals by the quality of the offspring 

 as suited to the production of energy or work in their various 

 phases of development. The mammary system should be 

 considered, therefore, as an important part of animal attain- 

 ments regardless of the specific use of the product obtained 

 from the individual or future generations. 



Reproductive System or Breeding Capacity. The measure 

 of value in a breeding animal is largely centered in its capacity 

 to reproduce like attainments of the individual in question. 

 The reproductive system, therefore, becomes an important 



