FEEDING STANDARDS— CALCULATING RATIONS 



91 



gaining nor losing in weight. Since mature animals can be main- 

 tained largely on roughages, let us see how nearly field-cured com 

 stover and oat straw will meet the requirements. As the standard calls 

 for 18 lbs. of dry matter, we will first try quantities of these feeds 

 which supply slightly less than this amount. 



If for the trial ration it is decided to feed 10 lbs. of com stover and 

 10 lbs. of oat straw for roughage, then, using the values for digestible 

 nutrients given in Appendix Table III, the calculations for dry matter 

 and digestible nutrients would be as given below: 



Corn stover, field-cured 

 In 100 In 10 



pounds pounds 



Dry matter 59.0 -f- 100 X 10 = 5.90 



Crude protein 1.4 ^ 100 X 10 = O.U 



Carbohydrates 31.1 -^ 100 X 10 = 3.11 



Fat 0.6 H- 100 X 10 = 0.06 



Oat straw 

 In 100 In 10 



pounds pounds 



88.5 -^ 100 X 10 = 8.85 

 1.0 -^ 100 X 10 = 0.10 



42.6 -f- 100 X 10 = 4.20 

 0.9-^ 100 X 10 = 0.09 



Arranging these results in tabular form, we have : 



First trial ration for maintaining IfiOO-lb. ox at rest 



This trial ration contains only about one-third the digestible crude 

 protein called for and also falls below the standard in dry matter and 

 carbohydrates. To improve it let us substitute 5 lbs. of clover hay, 

 which is high in protein, for the same weight of com stover, and add 

 0.5 lb. of protein-rich linseed meal. We then have : 



Second trial ration for maintaining 1,000-lh. ox at rest 



