CALCIUM AND PHOSPHORUS IN THE FEED OF DAIRY COWS. 11 



The manner in which the cows were fed and treated subsequent to 

 the birth of their first calves has already been discussed at some length 

 (pp. 1 to 3). It is only necessary to add a word about the actual 

 amounts of grain, hay, and silage given. The manner in which the 

 mature dry cows were fed has already been given (p. 2) . The mature 

 milking cows were generally fed 1 pound of grain mixture B or C 

 to each 3 pounds of milk given, 6 to 8 pounds of legume hay, and 

 as much corn silage as they would clean up. They usually gave 

 about 25 pounds of milk a day when they were fresh and at this 

 period they commonly got 8 pounds of grain mixture B, 8 pounds of 

 legume hay, and 30 pounds of corn silage. They usually got a little 

 thin with the progress of their lactation and were then fed somewhat 

 more grain in proportion to the milk yield. In the course of the year, 

 as has already been stated, they got a little more protein and total 

 nutriment than is required by the Eckles or Savage feeding standards. 



The bone-building elements can probably be supplied in sufficient 

 quantity in two different ways — either by feeding the ordinary ma- 

 terials much more liberally than the feeding standards require or by 

 adding calcium and phosphorus in the form of inorganic salts di- 

 rectly to the rations. We are confident that the latter method will 

 finally be adopted and will effect a great saving in the cost of pro- 

 ducing milk. 



But so radical a change in feeding practice ought, perhaps, to be 

 introduced slowly and with caution; the more conservative dairy- 

 man will probably prefer to keep to the ordinary farm feeds until 

 the effects of feeding inorganic salts of calcium and phosphorus have 

 been more fully worked out by the experiment stations. 



Our experience at Beltsville indicates that with many cows a 

 liberal ration fed for 4 to 6 weeks before calving easily pays for 

 itself through the increased flow of milk in the subsequent lactation 

 period, and we think that there are many cows throughout the country 

 which are far more valuable than their owners suppose them to be. 

 Those dairymen who have been feeding their animals according to 

 the standards or less should try giving each cow a period of two 

 months dry and feeding her during that period three or four times 

 the protein and two or three times the total nutriment required for 

 maintenance. The feeds used should contain plenty of calcium and 

 phosphorus — legume hay and a liberal proportion of bran and cotton- 

 seed or linseed meal. If dairymen find that the milk yield of any 

 of their cows is doubled by this process, they will run no risk of 

 reducing their profits by feeding those cows even 50 per cent more 



