148 ILLINOIS DAIRYMEN'S ASSOCIATION. 



However, all good dairy cows do not have large milk veins, 

 for the reason that some arteries may be large and receive the 

 larger portion of the blood from the udder. A large and well 

 developed circulation necessitates a large respiratory action to 

 purify the blood used in the skin. Not only that, but the heart, 

 which is the pump which circulates the blood, must be supplied 

 with energy by a well developed nervous system to keep up its 

 function. 



The blood is made from the food which the cow consumes. 

 In order to keep a steady supply of blood, there must necessarily 

 be a large digestion, and these are the important factors which 

 are closely connected for the production of milk, as also large 

 nose which must admit a large supply of air to the system, a 

 large mouth and large mastication to supply the digestive organs. 



According to the theory of evolution, we find mere traces 

 of these glands in the lower types of animals and animal life, 

 until they gradually develop from the various stages until these 

 particular glands reach their highest development in the dairy 

 cow. We find a thousand little milk tubes opening on the surface 

 of the skin. The secretion when liberated is licked off by the 

 young and supplies the food for their nourishment. These glands 

 assume a more compact form and a number of milk ducts empty 

 before opening on the outside of the skin. As we come up the 

 scale of life we find the development is more pronounced. Since 

 these conditions are natural facts, it indicates that there must be 

 a somewhat parallel development with the glands as well as 

 with the udder. 



Cows with large nervous systems are probably the most 

 efficient milk producers if kept in a good condition. A cow of 

 this nature reduces her flow of milk when ill-treated, and she 

 responds to good treatment. A strong or nervous temperament- 

 although not a large milk producer, is the best cow for the aver- 

 age farmer. Discomforts or ill-treatment do not affect the milk 

 supply as much as in the higher nervous animals. 



A dairyman should not alone rely on confirmation, for the 

 Babcock test and the scale with the milk pail and accurate meth- 



