MAKUAL OF CATTLE-FEEDIKa 427 



simple alteration of fodder. At tlie same time tlie fodder 

 can affect tlie quality of the milk to some extent 



Influence of Fodder on Percentage of Dry Matter. 

 — As already noted, the percentage of total dry matter in 

 milk may be considerably increased by rich feeding. This 

 is shown both in Wolft's and Kuhn's experiments (pp. 421 

 and 423), and has been fully conlirmed in many other inves- 

 tigations. In Wolft's experiments the addition to the fod- 

 der was solely protein. In Ivulm's experiments both protein 

 and non-niti'ogenous nutrients were added, but since other 

 experiments have shown that the addition of non-nitrogen- 

 ous nutrients to a ration does not affect essentially either the 

 quantity or quality of the milk, we must conclude that in 

 this case also it was the additional jprotem which caused 

 the gain. 



The increase in the proportion of dry matter in the milk 

 probably explains the common observation that it is possi- 

 ble to increase the yield of butter, e, g,^ from a given 

 amount of milk by means of proper feeding, although, as 

 we shall see, the ladder does not usually alter the propor- 

 tion of fat in the dry matter of the milk. 



Influence of Fodder on Composition of Dry Matter. 

 — In considering the influence of the fodder on the com- 

 position of the dry matter of milk there are certahi facts 

 that must be taken account of. 



It is a well-ascertained fact that the quality of milk, par- 

 ticularly its proportion of fat varies considerably from day 

 to day, and even from one milking to another. Moreover, 

 such variations are particularly liable to take place after a 

 change of fodder. As a consequence, any conclusions 

 based on a^^ingle or on a few analyses of milk, especially 

 if executed shortly after a change of fodder, have abso- 

 lutely no value. 



