242 PRODUCTIVE FEEDING OF FARM ANIMALS 



Composition of Ration for Dairy CowSj in Pounds 



According to the Armsby standard modified by Eckles, this cow, if pro- 

 ducing, say, 30 pounds of milk testing 4.03 per cent, should receive : 



Digestible Energy 



protein, value, 



pounds therms 



For maintenance 5 6.0 



For production 1.62 8.6 



Total 2.12 



14.6 



The cow did not, therefore, receive as much protein or as many therms 

 of energy values in the ratio given as called for by the standard; but the 

 difference is very likely apparent rather than real, since it. will be found, on 

 examination, that the digestible true protein in alfalfa hay, according to the 

 table, is very low, and probably lower than the actual content in average 

 alfalfa hay, which contains 11.0 per cent digestible crude protein. 



By the use of the table (p. 241) we find that the cow should receive 26 

 pounds dry matter, 2.4 pounds digestible protein, and 15.2 pounds digestible 

 non-nitrogenous components. These amounts agree closely with the cal- 

 culated composition of the ration, showing that this would furnish an ample 

 supply of nutrients for a 1000-pound cow producing about 1.3 pounds butter 

 fat a day. According to the Haecker standard,™ the cow would be entitled 

 to the following amounts of nutrients: 



Digestible 



Protein, 

 pounds 



For maintenance 70 



For production 1.62 



Total . 



2.32 



Carbohy- 

 drates and 

 fat, pounds 



7.3 



8.7 



16.0 



Also, in this case, there is a close agreement between the standard and 

 the composition of the ration calculated accordng to the average composition 

 of the various feeding stuffs. 



Feeding the Dairy Heifer. — The practice of good dairy farmers 

 as to the time of breeding heifers differs considerably. The best 

 results may, however, be expected by breeding so that the heifer 



10 Minnesota Bulletin 130. 



