206 THE CHEMISTRY OF CATTLE -FEEDING 



which to base an estimate. In these trials the animals were 

 fed on wheat middlings, and the quantities of food were 

 adjusted so as to keep them as nearly as possible without 

 gain or loss of weight. The author has calculated the thermic 

 energy of the food consumed and included the results with the 

 other data given in the table below. 



SANBORN'S EXPERIMENTS. 



The required amounts of thermic energy calculated by the 

 formula (p. 128) according to the size of the animals, are 4' 19, 

 10*23, 10*26, and 10*35 kt. in the four cases respectively. 

 The last case is probably the most reliable by reason of the 

 larger size of the animals, the larger number under experiment, 

 and the longer duration of the trial. It will be seen that the 

 calculated requirements correspond fairly closely with the food 

 actually consumed. In the first trial, the calculated amount 

 is 25 per cent, higher than that observed; but it should be 

 kept in view that pigs of that age would, under ordinary 

 circumstances, be growing rapidly, and as they did not gain 

 appreciably in weight they must have been losing in condition. 

 On the whole, it appears that the maintenance requirements 

 of pigs in terms of thermic energy differ from those of oxen 

 only in proportion to the size of the animals, and that the 

 formula previously given is applicable. 



The results of numerous trials at the various experiment 

 stations in America have been collated by Henry. 1 These 

 may be used to investigate the requirements for growth and 



1 " Feeds and Feeding." 



