Live Stock Breeders' Association. 197 



sented by the line d to e is the amount required to maintain the 

 animal's body, which is the same quantity as in the first case. How- 

 ever, the cut of one-fourth in the ration will be seen to come en- 

 tirely on that available for milk production and reduces that amount 

 one-half. 



Suppose that the ration of such a cow be still further reduced 

 to one-half of the full ration, or that required for maintenance 

 alone, as represented by the third line. In this case the cutting 

 down of the ration one-half would remove all available feed for 

 milk production. However, the animal would not cease producing 

 milk at once. This is a point of great importance in. feeding cows, 

 and a lack of such knowledge leads to serious errors in feeding. 

 The milk producing function is so strong that the cow will con- 

 tinue to produce milk for sometime, even when the feed is insuffi- 

 cient, utilizing the reserve material which has been accumulated in 

 the body in the past. This always happens in the case of a heavy 

 milking cow during the first few weeks after the birth of the calf. 

 At this time, it is not generally possible and not desirable on ac- 

 count of the condition of the animal to feed her a sufficient quantity 

 of feed to supply the nutrients necessary to produce the milk, and 

 even if the feed was offered, the appetite is not usually strong 

 enough to cause the necessary amount of feed to be taken to pre- 

 vent this loss in weight. As a rule, all heavy milking cows decline 

 in weight for the first two or three weeks, and occasionally for ten 

 weeks, after calving, which means that milk production has been 

 in excess of the feed supplied for that purpose. The same thing 

 happens in the case of the cow that is not fed a sufficient ration 

 for the amount of milk that she is producing. She may continue to 

 produce considerable milk for a while by drawing on the reserve 

 material of the body, but as soon as this is exhausted the produc- 

 tion of milk must come down to the amount available for this pur- 

 pose above the ration of maintenance. When the feed is in ex- 

 cess, the cow begins to store reserve material on her body. If the 

 amount of milk produced by a cow varied directly with the feed, 

 and she did not store up nutrients at one time and draw on reserve 

 material at another, it would simplify the problem of feeding very 

 much and result in more economical feeding at all times. 



How to Avoid Over-Feeding — While the statement and illus- 

 tration given apply to one class of dairy cows, there is another class 

 to which it does not apply, and with which it would lead to a ser- 

 ious mistake in feeding from an economical standpoint. This group 

 includes those of lower productive capacity which are liable to be 



