Oct. is, 1925 Calcium Phosphite as Supplement to Dairy Ration 
787 
Table V.— Composition of milk 
Period 
Total 
solids 
Fat 
Total 
ash 
Amount 
of ash in 
total 
solids 
Calcium 
Phos¬ 
phorus 
Preexperimental period, Jan., 1920, to 
Per cent 
Per cent 
Per cent 
Per cent 
Per cent 
Per cent 
Nov., 1921, whole herd--_. 
13.44 
4.83 
(•) 
C) 
(•) 
(*) 
Experimental period, Dec., 1921, to Apr., 
1924, whole herd. ___ 
13.23 
4.52 
0.722 
5.38 
0.119 
0.099 
Mineral group... 
13.40 
4.62 
.721 
5.28 
.122 
.099 
Nonmineral group. __ 
13.06 
4.42 
.723 
5.48 
.117 
.099 
« Not determined. 
The average content of total solids and fat has been slightly lower 
since the commencement of the experiment than it was during the 
two years previous, but this can be accounted for by the fact that 
since the experiment commenced the number of analyses of Jersey 
milk has been 6.94 per cent less than in the preexperimental period, 
while the analyses of Holstein milk have been 4.80 per cent greater. 
Due allowance having been made for this difference, it is seen that, 
taking the herd as a whole, the percentages of total solids and fat in 
the milk have not been materially affected by the conditions of the 
experiment. 
The average for the mineral group is slightly higher than for the 
nonmineral group, but a similar reason to that given above accounts 
for the difference. While the number of Jersey milks tested was 
identical for each group, there were 14.6 per cent more Holstein milks 
from the nonmineral group than from the mineral group, which 
explains the somewhat lower fat and solid test of the former. 
Respecting total ash and calcium and phosphorus, it is seen that 
with possibly one exception variations between the two groups are 
so slight as to be of no significance. The exception is calcium, which 
is slightly higher in the milks from the mineral group. It is possible 
that this may be due to the larger amount of calcium wmch the 
mineral group has received, but it is also possible that it may be due 
to inherited tendencies of the individual animals. As the figures 
are averages of 106 calcium determinations on milks from 18 different 
cows, it is unlikely that the difference is due to experimental or analyt¬ 
ical error. 
Effect on Reproduction 
Under this heading have been observed: 
(1) Recurrence of oestrum with respect to regularity and to the 
interval elapsing after calving before reappearance of oestrum. 
Regarding regularity, there are 19 individuals for which data are 
available. Scrutiny of their records reveals the following: 
Regularity 
Total 
Mineral 
group 
Non¬ 
mineral 
group 
13 
6 
7 
5 
3 
2 
1 
1 
0 
