HOW TO CALCULATE A RATION 285 



feed is an important matter, and should be carefully con- 

 sidered. Some feeding stuffs, like cotton-seed meal, oil 

 meal, or tankage, that are not common in some localities, 

 are easily purchased and shipped in by freight, and may often 

 be used with much advantage and profit. These are high- 

 class concentrates, and are extensively purchased by feeders 

 of stock in countries where but a comparatively small amount 

 of feed is grown, as in England and Holland, for example. 



The regulation of the ration to the animal's weight is 

 not difficult. If this cow had weighed 750 pounds instead 

 of 1000, then the total amount of dry matter and of each 

 nutrient would need to be decreased about one fourth, 

 or 25 per cent. If the ration was for a cow weighing 1250 

 pounds, then this would require an increase in the ration of 

 about one fourth. One does not change the proportions in 

 the feeding combination. It is simply a proportionate 

 increase or decrease in amount fed, to meet the needs of the 

 animal. 



Are the Wolff standards reliable? is a question quite 

 likely to be asked. Years ago, when the German tables 

 were first introduced to America, they were criticised by some 

 of our students of feeding. Several persons showed by 

 experiments that where animals were fed the maintenance 

 rations proposed by Wolff, that they would gain in weight. 

 Of course an animal should neither lose nor gain on such a 

 ration. Professor Haecker of Minnesota, and other experi- 

 menters, showed that Wolff proposed to feed more dry matter 

 and protein than was needed by the dairy cow, under certain 

 conditions. Haecker also considered that dairy cows should 

 be fed according to both the amount and quality of the milk. 

 In general, investigations in America have shown that less 

 protein is required for dairy animals than is given in the Ger- 

 man standards. Probably two pounds of protein, or very 



