48 



MAINTENANCE RATIONS OF FARM ANIMALS. 



SHEEP. 



Data regarding the maintenance rations of sheep are less com- 

 plete than for those of cattle. No experiments are on record in 

 which the requirement of available energy has been directly deter- 

 mined, and but few respiration experiments have been made. Most 

 of the recorded data are based upon live-weight experiments. 



In 1S67-GS Henneberg and liis associates 1 conducted a series of respiration 

 experiments upon two mature sheep receiving approximately a maintenance 

 ration of meadow hay. Two digestion experiments, including determinations of 

 the nitrogen balance, were made with each of the animals. During each of 

 these digestion experiments three respiration experiments were made upon the 

 two animals together. The results of these determinations vary so little that 

 their average is sufficient for our present purpose. Estimating, as in some of the 

 experiments on cattle, that each kilogram of digestible organic matter contains 

 approximately 3.5 therms of metabolizable energy, and further, that, as in the 

 case of Kellner's steers, 43 per cent of the metabolizable energy of the feed 

 could be stored up in the form of gain of flesh and fat, the following computa- 

 tion per day and head may be made : 



Maintenance ration of sheep — Henneberg and Stohmann. 



Live weight, exclusive of wool kilograms 45. 4 



Digestible organic matter per day grams 539. 1 



Gain by animal : 



Protein do 7. 95 



Fat do 13. 75 



« 



Therms. 



Metabolizable energy of ration 0.5391X3.5 1.887 



Metabolizable energy equivalent to gain : 



Therm. 



Protein, 0.00795 kilo. X 5.7 0.0453 



Fat, 0.01375 kilo. X 9.5 . 1306 



. 1759 -K>. 43 . 409 



Metabolizable energy for maintenance 1. 478 



The foregoing ration is equivalent to 1.574 therms per 50 kilograms, or 

 1.475 therms per 100 pounds, computed in proportion to the two-thirds power of 

 the live weight. 



In 1872 Henneberg, Fleischer, and Miiller 2 began a series of respiration 

 experiments upon sheep in which wheat gluten was added to a basal ration of 

 hay and ground barley. The basal ration of the first period proved to be but 

 slightly greater than the maintenance ration. Making the same calculations as 

 before, but assuming that 50 per cent of the metabolizable energy of the ration 

 might serve for the production of gain, since a portion of the ration consisted 

 of grain, we have the following: 



1 Neue Beirrage, etc., pp. 68-286. 



2 Jahresbericht der Agriculturchemie, vol. 16-17, II, 145. 



