CHAPTER IV 



FEEDING FOR MILK 



IN feeding cows for milk the most essential fact to grasp is that 

 the composition of milk cannot be altered to any extent by feed- 

 ing. The solids may be increased slightly by a food very rich 

 in protein, or, on the other hand, the solids may be lessened, if 

 the diet is very watery, but the percentage of fat, sugar and pro- 

 teids in the milk is not affected to any degree by different kinds of 

 foodstuffs. One often reads of the marked influence of a change 

 of food in increasing, or otherwise, the percentage of fat in the 

 milk. But, while a sudden change in the ration may produce a 

 corresponding alteration in the percentage of fat in the milk, it will 

 be found only a temporary matter. The single exception to the 

 rule that the composition of milk is not changed by feeding is when 

 the animals are not in a normal condition. If an animal has not 

 enough food to be maintained in a normal condition, there may be 

 a disturbance of the functions of the udder, as of any other function 

 in the body, and therefore alteration in the composition of the milk. 

 The theory adopted by many physiologists teaches that milk 

 is formed by the constant breaking down of the substance of the 

 cells of the udder into the proteids, fat, and perhaps to some 

 extent the sugar, of milk. This process is followed by a rapid re- 

 building of the udder cells. But, while it was formerly thought 

 that the entire udder cells were being continually destroyed in the 



* Consult also page 351 for recent advances in the science of feeding animals. 



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