CALCIUM AND PHOSPHORUS IN THE PEED OF DAIRY COWS. 19 



corn silage. March 11 to 28, 3 pounds grain mixture C, 4 pounds alfalfa hay, 

 24 pounds corn silage ; rations not alternated. March 29 to April 25, same as 

 for February 3 to March 10. 



Cow 6-'f, 1918-19. — December 19, 1918, to January 5, 1919, 5 pounds grain mix- 

 ture C, 4 pounds alfalfa hay, 30 pounds corn silage. January 6 to February 6, 

 1919, 6 pounds grain mixture O, 5 pounds alfalfa hay, 30 pounds corn silage. 



Cow 67, 1918. — April 1 to 20, alternated rations with daily average of 3 pounds 

 grain mixture CP 2 , 4 pounds alfalfa hay, 30 pounds corn silage. 



Cow 70, 1918-19.— October 19, 1918, to January 27, 1919, alternated rations 

 with daily average of 3 pounds grain mixture CPi, 4 pounds alfalfa hay, 30 

 pounds corn silage. 



Cow 71, 1918. — September 25 to December 1, 3 pounds grain mixture C, 4 

 pounds alfalfa hay, 30 pounds corn silage. December 2 to 11, 5 pounds grain 

 mixture C, 4 pounds alfalfa hay, 30 pounds corn silage. 



Cow 71, 1919-20— December 20", 1919, to February 20, 1920, alternated rations 

 with daily average of 3J pounds grain mixture CP, 4 pounds alfalfa hay, 30 

 pounds corn silage. February 20 to March 1, 1920, alternated rations with daily 

 average of 5| pounds grain mixture CP, 4 pounds alfalfa hay, 30 pounds corn 

 silage. 



Cow 81, 1919. — February 24 to April 24, 1919, 3 pounds grain mixture E, 3 

 pounds alfalfa hay, 30 pounds corn silage, 5.7 grams calcium as calcium chlorid 

 daily. 



Cow 81, 1920. — February 13 to April 6, alternated rations with daily average 

 of 31 pounds grain mixture CP, 3 pounds alfalfa hay, 30 pounds corn silage. 



Cow 213, 1918. — January 1 to February 6, 5.6 pounds grain mixture C, 3 pounds 

 soy-bean hay, 8 pounds corn stover, 25 pounds corn silage. 



Cow 214, 1918. — March 28 to May 6, alternated rations with daily average of 



3 pounds grain mixture CP 2 , 4 pounds alfalfa hay, 30 pounds corn silage. May 

 7 to 15, alternated rations with daily average of 5 pounds grain mixture CP 2 , 



4 pounds alfalfa hay, 30 pounds corn silage. May 16 to 27, alternated rations 

 with daily average of 5 pounds grain mixture CPi, 4 pounds alfalfa hay, 30 

 pounds corn silage. 



ANIMALS WHICH HAD BEEN ON TEST DURING THE YEAR PRECEDING THE EXPESRI- 



MENTS. 



For a month or so before they calved previous to the test lactation period 

 these animals were fed daily rations of from 8 to 18 pounds of grain mixture F, 

 10 to 16 pounds alfalfa hay, and 24 to 30 pounds corn silage. The grain mix- 

 tures fed contained more protein and ash than either grain mixture C or D. 

 The rations supplied a great excess of both protein and total nutriment above 

 the maintenance requirements. 



After they had finished their tests, these animals were dried off about two 

 months before they were due to calve. Cows 227, 232, and 240 were selected as 

 controls and were fed 3 pounds grain mixture D, 5 pounds alfalfa hay, and 30 

 pounds corn silage for 60 days before calving. Cows 228, 229, and 248 served 

 as experimental animals. For 60 days before calving they were fed alter- 

 nated rations with a daily average of 31 pounds grain mixture DP, 5 pounds 

 alfalfa hay, and 30 pounds corn silage. 



