THE COMPUTATION OF RATIONS 693 



tensively, but here he encounters the law of diminishing re- 

 turns. The dairy cow affords, perhaps, the most striking il- 

 lustration of this. An increase in the quantity of her feed above 

 a moderate ration may be expected to cause an increase in milk 

 secretion but at the same time an increasing proportion of the 

 extra feed will be diverted to fattening (606-610). Similarly, 

 a rather small protein supply appears adequate to support mod- 

 erate milk production but larger amounts seem to act as a stim- 

 ulus to the activity of the milk glands and to increase the yield 

 of milk (603), but presumably at a diminishing rate. The dairy- 

 man's problem is to utilize these stimulating effects up to the 

 point at which the increase in yield is offset by the added cost 

 of the ration, and the solution of this problem requires ex- 

 perience and good judgment and is one in which little aid can 

 be afforded by feeding standards. 



What is so emphatically true of dairy feeding applies in 

 greater or less degree to all forms of animal production. Even 

 though there may be no decrease in the utilization of the 

 feed in the strict physiological sense, diminished digestibility, 

 stimulation of incidental bodily activity, or changing com- 

 position of increase tend to make heavy rations or high 

 protein rations relatively less effective than more moderate 

 ones. 



What the feeder needs in order to meet this situation intel- 

 ligently is not so much a fixed standard, or group of standards, as 

 a knowledge of the amount and kind of feed required under 

 various conditions for the manufacture of a unit of product 

 a pound of increase in live weight, for example, or a pound of 

 milk of a given quality. To the extent to which this infor- 

 mation is available he can, knowing his animals, proportion 

 the feed to the capacity of each and thus go far toward securing 

 the most efficient production. It appears desirable, therefore, 

 to assume a somewhat different point of view from that which 

 has largely prevailed in the past and to substitute for the con- 

 ception of feeding standards the modified conception of feed 

 requirements. 



796. Feed requirements. Haecker l appears to have been 

 the first to apply this idea to milk production and to formulate 

 the feed requirements for the production of a pound of milk 

 / l Minn. Expt. Sta., Bui. 79 (1903), pp. 104-107. 



