MAINTENANCE RATION AND BATTENINGS 



443 



COMPONENTS OF A FAT AND A LEAN SHEEP, SHOWING THE 

 COMPOSITION OF THE GAIN IN FATTENING. 



The average increase in body substance on fattening, exclusive 

 of offal, from the experiments on oxen, sheep, and swine at the 

 Rothamsted Experiment Station is as follows: 



Proteids 7.5 



Fat 66.6 



Mineral matter 1.5 



Water 24.4 



IOO.O 



It is seen that the increase is mostly fat, only a small part being 

 proteids. The nutritive ratio of this gain is 1 : 20. These 

 animals were not entirely grown. Grown animals, if in fair con- 

 dition, gain very little flesh (proteids) when fattened. 



Factors which Influence the Fattening Ration. A number of 

 factors influence the fattening ration: 



Requirements for Maintenance. Since only the excess of the 

 productive value of the food over the maintenance requirements 

 may be used for fattening, anything which affects the mainten- 

 ance requirements will affect the fattening ration. An increase 

 in the maintenance requirements will decrease the gain in fat. 



Stall Temperature. On account of the heavy ration fed, the 

 animal has a large excess of thermal energy, and the temperature 

 of the stall may fall lower than when fed on a maintenance ration 

 without affecting the amount of fat gained. But if the stall be- 

 comes too cold, maintenance requirements are increased and the 

 animal gains less fat. If the animal has to warm the water con- 

 sumed in cold weather to the body temperature, the maintenance 

 requirements may be considerably raised. A large proportion of 

 the material otherwise available for fat might be so used. It has 



