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ORGANIC AGRICULTURAL CHEMISTRY 



TABLE XIV 

 Fuel Values of Food Constituents for Cattle (Kellner) 



FOOD REQUIREMENT 



Energy Requirement 



Maintenance Requirement. — The energy represented by 

 these figures is the amount per gram or pound of actually 

 digested nutrient which cattle are able to utilize in metabolism. 

 This energy is either liberated in the form of body heat or 

 muscular work, the latter being both the involuntary work of 

 the body and the voluntary work of labor ; or, the equivalent 

 nutrient is stored as body substance (mostly fat), in case it is 

 in excess of the energy demands of the body. 



The energy which it is necessary to supply in food for the 

 purpose of maintaining the life of the animal (body heat + in- 

 voluntary muscular work) is known as the maintenance require- 

 ment and a ration which supplies this only is termed a main- 

 tenance ration. 



The energy of this maintenance requirement is expended in 

 performing the essential operations of the body and keeping 



