Sept. 17, 1917 Energy Values of Hominy Feed and Maize Meal 



607 



ENERGY EXPENDITURE CONSEQUENT ON FEED CONSUMPTION 



It is a familiar fact that the consumption of feed tends to stimulate 

 the metabolism of an animal, as is manifested by the increased amount 

 of heat produced. The energy thus expended, as well as the chemical 

 energy escaping in the excreta, must be deducted from the gross energy 

 of a feeding stuff to obtain its net energy value. In this experiment 

 the losses of energy in heat production per kilogram of dry matter, 

 computed as in previous papers, are recorded in Table XII. 



Tabi,^ XII. — Increment of heat production per kilogram of dry matter 



Feedstuff. 



Mixed hay. 

 Do 



Average 



Mixed hay and hominy feed . 

 Mixed hay and maize meal . . 



Computed for hominy 

 feed 



Computed for maize 

 meal 



Ani- 

 mal, 



No. 



Periods 

 compared. 



Total in- 

 crement 

 per kilo- 

 gram. 



I and 5 

 I and 5 



Calories. 



928 



1,031 



Analysis of increment. 



Stand- 

 ing 12 

 hours. 



Calories. 



94 



Calories. 



5 

 4 



2 and 3 

 2 and 7, 



2 and 3 

 2 and 3 



1,147 

 1,297 



1,434 



67 



36 



287 



30 

 386 



Rising 



and 



lying 



down. 



Calories. 

 118 



137 



Meth- 

 ane fer- 

 menta- 

 tion. 



123 

 132 

 140 



146 

 146 



Re- 

 main- 

 der. 



Calories. 

 764 

 806 



972 



871 



I, 180 

 906 



One kgm. of maize dry matter appears to have caused a somewhat 

 greater increase (about 5 per cent) in heat production than the same 

 amount of hominy feed. A marked difference is manifested in the 

 proportion of the increase due to standing, while the heat evolved by 

 fermentation is substantially equal, and the direct stimulus to the 

 metabolism ("remainder") is less with maize. The total difference is 

 probably not very significant. 



NET ENERGY VALUES 



By subtracting from the gross energy of the hominy feed and maize meal, 

 respectively, the losses of chemical energy in the feces, urine, and methane, 

 as shown in Table IX, and the energy expenditure consequent upon its 

 consumption as measured by the increment of heat production shown 

 in Table XII, the following net energy values for the two feeding stuffs 

 may be computed. Later investigations on maize meal (3), however, 

 led to the conclusion that the figure obtained in this experiment for the 

 heat expenditure in feed consumption was too high, and that 1,289 

 Calories per kilogram of dry matter was more nearly correct. The 

 results in Table XIII are computed, using both factors. 



