on the other hand, to calculate the amount of potential energy 

 which would have been lost by the animal had the ration been 

 reduced to zero. 



Thus in the case of the pure-bred steer in the experiments 

 of 1907 for example, the metabolizable energy of the hay consumed 

 daily in Period III was 6234.5 Calories and on this ration the body 

 lost daily 1679.4 Calories, while a comparison with Period IV 

 showed an availability of the metabolizable energy of 57.05 per cent. 

 Evidently, then, to prevent the loss from the body of 1679.4 Calor- 

 ies it would have been necessary to add to the daily ration suffi- 

 cient hay to supply. 



1679.4-^0.5705=2943.7 Calories 



of metabolizable energy, making the total metabolizable energy of 

 the daily ration 



2943.7+6234.5=9178.2 Calories. 



If, on the other hand, the ration has been reduced to zero, 

 the loss of energy per day by the animal would have been increased 

 by 



1634.5X0.5705=3556.8 Calories. 



and 'the total loss would have been 



1679.4+3556.8=5236.2 Calories. 



A ration, therefore, supplying 5236.2 Calories of available en- 

 ergy would have been a maintenance ration for this animal. 



Computed in the manner shown in the foregoing example, 

 the maintenance requirements of the two animals in the three 



Table 5. Computed Maintenance Requirements in Terms of 

 Available Energy. 



