PART FIRST. 



Feeding and rattening Young Steers and Cattle. 



IT has already been pointed out that the value of an animal siderations reja . 

 and the facilities for fattening, depend upon the amount of fat tjve to the for- 

 already stored up. mation of fat. 



Fats in fodders may be reabsorbed and deposited in the body 

 without undergoing any special change; fats that have an en- 

 tirely different composition from that of the body are not reab- 

 sorbed, but must undergo many combinations before being 

 assimilated. It then becomes evident that the fat of fodders is 

 not necessarily stored up at once, notwithstanding that their 

 composition is very much the same as animal fats. 



The problem consequently is to determine which are the 

 nutrients that supply the greater part of the fat deposited. The 

 principal groups to be considered are the albuminoids and carbo- 

 hydrates, as it is mainly from them that the fat is derived. 



From the knowledge at our disposal, we conclude that part of 

 the protein of fodders when it does not undergo a fermentation 

 in the intestines may generate fat, which, as a general thing, is 

 burned during the act of respiration at the same time as the 

 digestible fat furnished with the fodder. It is maintained that 

 the only way of explaining the formation of fat in the body from 

 a given food is to consider the fat in the ration, and then what is 

 formed by the splitting up of the protein of the feed. The in- 

 teresting problem now before us is to determine how domesti- 

 cated ruminating animals store up fat, and how this can be ac- 

 complished to the best advantage, as is necessary in systems 

 of fattening and in meat production. The only solution within 

 our reach is the determining of the efficiency of a ration by the 

 increase of weight after fattening. 



Investigators have frequently been too hasty in declaring 



(9) 



