APPENDIX 245 



This mixture, containing slightly more protein, would cost 16.6 

 cents for the day's feeding or $41 . 50 per ton. 



Of course this method is too complicated for regular use. The 

 methods for putting together rations we have discussed in Chapter 

 II are more practical. However, the question frequently comes 

 up as to whether a given ration contains enough protein, or as to 

 whether a cow is getting the right amount of nutrients for her 

 production. Her ration can be easily checked up against the 

 feeding standard. Finding whether a ration corresponds to the 

 standard is much simpler than trying to make one fit it. For 

 example, is 10 pounds of mixed hay, 25 pounds of silage and 8 

 pounds of equal parts of wheat bran and gluten feed a satis- 

 factory ration for a 1200-pound Holstein cow producing 25 pounds 

 of milk? Such a question came to us recently. The nutrient con- 

 tent of the ration works out as follows: 



-,-, j Dry Digestible 



Feeds Matter Protein T.D.N. 



10 lbs. mixed hay 8.72 .430 5.13 



25 lbs. corn silage 6.58 .275 4.43 



4 lbs. wheat bran 3.60 .500 2.44 



4 lbs. gluten feed 3.65 .864 3.23 



Totals 22.55 2.069 15.23 



The cow's requirements are as follows, assuming 3.5 per cent 

 milk: 



Digestible 

 Protein T.D.N. 



For maintenance . 840 9 . 51 



For 25 lbs. of 3.5% milk 1.375 7.5 



Totals 2.215 17.01 



Thus, the ration is adequate as regards protein but low in total 

 digestible nutrients and dry matter. It could be corrected by 

 increasing the roughage. This would probably also add more 

 protein than necessary, making it possible to substitute at least 

 one pound of a lower protein concentrate which would cheapen the 

 grain ration, or perhaps one pound of the concentrates could be 

 omitted without further addition. However, the grain ration lacks 

 variety as it stands. 



