22 
BULLETIN 945, U. S. DEPARTMENT OF AGRICULTURE. 
It would, perhaps, be fair to compare cow 59 with cows 67 and 
TO ; cow 64 with cow 21 ; and cow 213 with cow 214. The figures for 
cow 59 represent approximately the average performance for the 
heifers of the general herd with their first calves. Cow 67 is a 
half sister of cow 59. The two animals have the same sire; the 
dam of 67 has a somewhat better record than that of 59. Cow 70 
was selected in order to try the effects of phosphate feeding in an 
unfavorable case. Her mother had the poorest record of all the cows 
in the herd except two, and she herself was of unpromising appear- 
ance. Cow 64 was milked only twice a day ; and cow 21 three times. 
The difference in the milk yields is, however, larger than is generally 
produced by this difference in treatment. Cows 213 and 214 were 
half sisters, both being daughters of the same sire. The dam of 
cow 213 had a decidedly better record than the dam of cow 214. 
Cow 213 was milked only twice a day, and cow 214 three times, but 
the difference in milk yields is very much greater than could be ac- 
counted for by this difference in treatment. 
Table 3. — Animals ichich had ~been on test during the year preceding the periods 
of control and phosphate feeding. 
CONTROLS. 
Date of birth. 
Breed. 
Date of calving. 1 Days dry. 
Milk yield.i 
Fat yield. 1 
g 
03 
d 
Test period. 
After control 
or phosphate 
feeding. 
Before 
test 
period. 
9 
ft <D 
O 
"S-2o 
U 03 Tj 
■d 
# o 
© 
ft 
I 
_03.2 
o _, C 
aft^ 
< 
o 
I 
1 
EH 
o 
tail 
ill 
< 
227 
232 
9 40 
Aug. 2,1915 
Mar. 31,1916 
Nov. 10, 1914 
Holstein 
do 
...do 
Apr. 18,1918 
Nov. 29,1918 
Sept. 27, 1918 
Jan. 11,1920 
Mar. 15,1920 
Feb. 9, 1920 
Days. 
First 
calf. 
...do.. 
59 
Days. 
137 
58 
112 
Lbs. 
1,674 
1,591 
1,876 
Lbs. 
2,019 
2,046 
1,881 
Lbs. 
61.8 
45.5 
64.2 
Lbs. 
83.8 
67.5 
80.9 
EXPERIMENT ANIMALS. 
228 
Sept. 2,1915 
Nov. 8, 1915 
Mar. 15,1916 
Holstein. 
....do... 
...do... 
Apr. 4, 1918 
May 28,1918 
Jan. 22,1919 
Dec. 30,1919 
Jan. 31,1920 
June 17,1920 
First 
calf. 
...do.. 
...do.. 
79 
1,429 
1,817 
1,594 
2,016 
2,078 
1,611 
44.7 
53. S 
51.0 
64 ! 
71.7 
45.1 
i The figures in these columns represent the milk and fat yields from the tenth to the fortieth day after 
calving, except in the case of cow 229. In her case they represent the milk and fat yields from the twentieth 
to the thirty-fifth day after calving multiplied bv 2. It was necessary to take these figures i nstead of the 
usual ones, as she was sick for some days after caiving in 1920, and suffered a severe cut in her rations, and 
she became sick again on the thirty-sixth day after calving. 
It is not necessary to make any detailed comment on the results 
given in Table 3. 
The differences in milk yield as between the cows fed phosphate and 
those fed the basal ration alone are so small as to be insignificant. It 
follows that the favorable influence of the phosphate feeding is 
