THE VALUATION OF FEEDINGSTUFFS 333 



pended in digestion, and thus are more accurate in compar- 

 ing feeds differing greatly in the amount of energy expended 

 in their digestion. For example, 100 pounds of corn and 100 

 pounds of alfalfa hay contain 84.3 and 53.0 pounds of total 

 nutriment respectively. In other words, alfalfa hay con- 

 tains nearly two-thirds as much total nutriment as the same 

 amount of corn. However, 100 pounds of corn contain 

 88.8 therms of net energy, while the same amount of alfalfa 

 hay contains 34.4 therms, or only about one-third as much 

 as the corn. The difference, as previously stated, is due to 

 the larger amount of energy expended in digestion of the hay. 



It should be remembered that the comparisons between 

 concentrates and roughages may not always be as accurate 

 by any means as when one compares similar feeds. How- 

 ever, by using his practical knowledge and common sense 

 the feeder can usually determine the most economical com- 

 binations of feed to use. 



In general, whenever there is doubt as to which feed is 

 most economical, the stock-feeder should calculate the cost 

 of several rations, using his home-grown feeds as their 

 basis and trying the effect of different supplements upon the 

 cost of the rations. However, it is not exactly fair to use 

 the current market prices as the values of the farm-grown 

 feeds, unless it costs nothing in time and labor to market 

 them. One should deduct from their value at the market 

 a reasonable allowance for hauling them to market. On 

 the other hand, one also should make some allowance for 

 the time and labor expended in hauling purchased feed to 

 the feed lots. 



