16 



BULLETIN 459, U. S. DEPARTMENT OF AGRICULTURE. 



amounts of digestible protein which should be contained in the 

 rations of cattle and sheep at different ages to insure satisfactory 

 growth. These estimates are contained in the following table. They 

 are expressed in pounds per head and include the maintenance require- 

 ment. As a master of convenience, the table also contains the esti- 

 mated net energy values required per head for normal growth, and 

 it thus constitutes a set of approximate feeding standards. In their 

 use the weight rather than the age of the animal should be the con- 

 trolling factor. 



Estimated requirements l per day and head. 

 FOR GROWING CATTLE. 



Months. 



3 



6 



9 



12 



18 



24 



30 



Beef breeds. 



Live 

 weight. 



Pounds. 

 200 

 350 

 450 

 550 

 750 

 900 

 1,000 



Digestible 

 protein. 



Pounds. 

 0.S0 

 1.10 

 1.25 

 1.40 

 1.50 

 1.60 

 1.60 



Net energy 

 value. 



Therms. 

 4.2 

 5.0 

 5.7 

 6.5 

 8.2 

 9.3 

 9.9 



Dairy breeds. 



Live 

 weight. 



Pounds. 

 165 

 275 

 325 

 400 

 550 

 700 

 800 



Digestible 

 protein. 



Pounds. 

 0.65 

 .85 

 .90 

 1.00 

 1.10 

 1.20 

 1.20 



Net energy 

 value. 



Therms. 

 3.6 

 4.1 

 4.4 

 5.1 

 6.4 

 7.6 

 8.2 



FOR GROWING SHEEP. 



Age. 



Mutton breeds. 



Wool breeds. 



Live 



Digestible 



Net energy 



Live 



Digestible 



Net energv 





weight. 



protein. 



value. 



weight. 



protein. 



value. 



Months. 



Pounds. 



Pounds. 



Therms. 



Pounds. 



Pounds. 



Therms. 



6 



72 



0.31 



1.05 



65 



0.28 



0.95 



■ 9 



98 



.27 



1.20 



82 



.23 



1.05 



12 



115 



.24 



1.35 



90 



.20 



1.15 



15 



130 



.24 



1.50 



95 



.18 



1.18 



18 



150 



.23 



1.65 



100 



.15 



1.20 



1 Including the maintenance requirement. 



No satisfactory data for colts are available, while, as noted on page 

 10, our knowledge of the relative values of feeding stuffs for swine is 

 somewhat deficient. 



REQUIREMENTS FOR FATTENING. 



The foregoing data refer to what might be called normal growth, in 

 which the animals are kept in a good thrifty condition, but do not 

 become fat. If any considerable fattening is desirable, somewhat 

 heavier rations must be given in proportion to the amount of gain 

 made, because the increase gain in fattening animals consists to 

 a very large extent of fat and therefore means the storing up by the 

 animal of more reserve energy. For fairly mature fattening ani- 



