CATTLE. 227 



Cows should be kept in clean and sanitary stables. 



.They should be kept in good physical condition. 



They should not suffer from exposure to excessive rains 

 or cold weather. 



The study of individual cows is essential to successful dairy- 

 ing because : 



There is a variation in the needs of different animals. 



The needs of the same animal differ from time to time. 



Feeds must be varied according to the condition of the cow ; 

 according to the quantity and quality of milk. 



NOTE. See table of digestible nutrients required per day by a 1,000 

 pound cow giving different amounts and qualities of milk (p. 230). 



Net energy is what is available for milk production and main- 

 tenance after deducting the losses in labor of mastication, diges- 

 tion, gas, etc. 



Maintenance is the required amount of food to keep a cow 

 alive, without giving milk, growing or gaining in weight. 



Composition of Feeds and Their Influences on the Composi- 

 tion of Milk. 



PROTEIN. 



Protein is a compound that contains nitrogen which is very 

 costly in feeds and so we secure large quantities of it, from the 

 air, for dairy purposes through clover, alfalfa and other legumes. 



Protein in the dairy cow produces or forms blood, muscle, 

 connective tissue, tendons, etc., as well as the casein and albumen 

 in the milk. 



Protein forms nearly one-third of the solid material found 

 in milk. 



The average nutritive ratio of the digestible nutrients re- 

 quired by a dairy cow is about i :6. Protein is therefore about 

 one-sixth of the nutrients in the ration. The dairy cow therefore 

 requires food rich in protein, such as, linseed meal, gluten feed, 

 bran, cotton-seed meal and other concentrates. 



