488 Journal of Agricultural Research voi in. no. e 



if less fundamental methods. Kellner's scheme recognizes this fact and 

 his deduction for crude fiber and his factors for relative values (Wertig- 

 keit) are at bottom simply a method of applying the aggregate net 

 results on typical feeding stuffs to other materials. The method here 

 proposed seeks to do exactly the same thing more directly and simply, 

 relating the energy content and the necessary deductions to the total 

 dry matter or total digestible matter of the feeding stuff, independently 

 of its chemical composition. It is true that the data for so doing are 

 somewhat meager, but, except as Kellner has utilized unpublished data 

 in the fonnulation of his tables, they are just as abundant in the one 

 case as in the other. It is greatly to be regretted that Kellner's results 

 have not yet been published in full. When they become available they 

 will doubtless greatly broaden the basis for such computations. 



SUMMARY 



There are reported the results of 76 experiments with the respiration 

 calorimeter upon nine steers in which the balance of matter and of 

 energy was determined. 



The losses of feed energy from the animal are of two classes: (i) 

 Losses of unused chemical energy in the feces, urine, and methane; and 

 (2) losses in the form of heat due to the increased metabolism consequent 

 upon the ingestion of feed. 



(i) Losses of chemical energy. — The losses of energy in methane 

 and urine were relatively greater on light than on moderately heavy 

 rations. 



Neither the losses of energy in the feces nor the total losses showed a 

 distinct relation to the amount of feed consumed. 



Individual differences between animals had no very material influence 

 on the losses of chemical energy. 



The losses of energy in methane may be computed approximately 

 from the amount of total carbohydrates digested. 



The metabolizable energy per kilogram of digested organic matter 

 showed but slight variations within the same class of feeding stuffs. 



(2) Losses of heat consequent upon feed consumption. — The 

 heat production is notably greater during standing than during lying, 

 and the difference is greater on heavy than on light rations. 



The increment of heat production during standing is affected by the 

 individuality of the animal and by the kind of feed consumed. 



An approximate partial analysis of the heat production of the animal 

 into its principal factors is attempted. 



The average energy expenditure consequent upon the consumption of 

 I kg. of dry matter is reported for 1 1 different feeding stuffs. 



The expenditure of energy arising from the consumption of the coarse 

 feeds is not on the whole materially greater than in the case of the con- 

 centrates. 



The increased muscular work of the digestive organs appears to be a 

 relatively small factor of the increased heat production. 



A scrub steer showed a somewhat greater increment of metabolism 

 consequent upon feed consumption than did a pure-bred beef animal. 



