34 Bulletin 81 



5. relative value of grain feeds and byproducts 



A very pertinent question presents itself as to the relative worth of 

 sundry feeds. This inquiry often takes concrete shapes as follows: Is gluten 

 feed cheaper than bran considering the food it contains ? Are oats too ex- 

 pensive to feed cows ? Can the farmer afford to feed timothy hay to cows 

 when he can get or grow clover hay to replace it at the same price at which 

 the former sells? 



Several attempts have been made to place definite money values on 

 feeds, basing these on their nutrient contents. These attempts have not 

 been so successful as might be wished. Mathematical processes have been 

 used, but untrustworthy results obtained. The value of one feeding stuff 

 as compared with another, calculations being based on the nutrients they 

 contain, cannot be stated with any assurance of accuracy. The value of a 

 pound of digestible dry matter in any feed, however, can be readily found 

 at any time. But the usefulness of this calculation is lessened by the fact 

 that many feeds are bought primarily to furnish digestible protein rather 

 than dry matter ; hence comparisons based on the latter may be misleading. 

 It has been proposed by some to meet this objection in the following man- 

 ner : Some definite price is assumed for a pound of digestible carbohydrates 

 and fat ; the ton price of the feed is lessened by the assumed valuation of 

 the weight of these nutrients present ; and the remainder is as- 

 sumed to be the money value of a pound of the digestible pro- 

 tein, from which the pound values are readily ascertained. This 

 proposition, while open to criticism, has, likewise, some degree of merit. 

 It is felt, however, that the results of such a calculation have at best but 

 a doubtful value. Yet the demand for some numerical expression of rela- 

 tive values is urgent, and, in order to meet this in some measure, two tables 

 are presented. The first shows for the more common feeds the assumed 

 prices for 100 pounds at ton rates, the pounds of total digestible nu- 

 trients ', and the price per pound of the same. The second shows the first 

 two items given in the first table, and, also, the pounds of average digestible 

 protein, the pounds of average digestible carbohydrates and ether extract, 1 

 the latter multiplied by one-half cent (an assumed price for carbohydrates, 

 etc.), the price per pound for digestible protein based on the foregoing as- 

 sumptions ; and, finally, it shows the relative standing of the feeds on the 

 hundred basis as to economy, corn being selected as standard for those 

 feeds low and bran for those feeds high in protein, the reasons for their 

 choice being their large use in cattle feeding. 



Attention is called in particular to the fact that the whole scheme rests 

 on assumptions, some of which have but little foundation. The ton prices 

 used simply represent in a very general way the prices of recent years in 



i Ether extract is multiplied by 2.25. See foot note page 20. 



