CALCIUM AND PHOSPHORUS IN THE FEED OF DAIRY COWS. 2f 
aborted after a period on the phosphate feeding might give more 
milk than they ever had before. We have no knowledge of the 
amount of her milk yield after the abortion. 
Besides the cases so far reported, there are only seven animals 
which received any sodium phosphate at all. One of these received 
small daily doses (6.9 grams phosphorus as sodium phosphate) from 
the time she was born to when she dropped her first calf. She 
aborted with this calf, and gave a rather small quantity of milk sub- 
sequently. On account of the abortion and of the fact that the doses 
of phosphate were small, we do not think that this experiment throws 
any light at all on the question of the effects of phosphate feeding on 
the subsequent milk yield. 
The six other animals received basal rations alone and then the 
same rations with phosphate added for short alternated periods, the 
main purpose of the experiments being to determine the effects of 
feeding phosphate on the concentration of phosphorus in the blood. 
Three of these happened to abort after periods of a week or more on 
rations without phosphate. They gave about the quantities of milk 
which would have been expected on the supposition that they had 
never had phosphate. 
The other three dropped their calves while on the phosphate feed- 
ing. Two of them aborted after 7 and 10 days of phosphate feeding 
respectively. Both gave more milk than they ever had before, and 
decidedly more than would have been expected on the supposition that 
they had* never had phosphate. The third was a heifer carrying her 
first calf. She calved normally at term after 26 days of phosphate 
feeding and gave much more milk than the general average for the 
herd with their first calves. These last three results suggest that even 
a short period of phosphate feeding may have a markedly favorable 
effect -on milk yield if it occurs during the few days immediately 
before calving, during which the udder is rapidly enlarging in prep- 
aration for the coming lactation period. 
LITERATURE CITED. 
(1) Beetbam, J. 1878. Ueber die Ausscheidung der Phosphorsaure bei den 
Pflanzenfressern. In Ztschr. Biol., v. 14, pt. 3, p. 335-382. 
(2) Eckles, C. H. and Palmee, L. S. 1916. The influence of the plane of 
nutrition of the cow upon the composition and properties of milk and 
butterfat. Mo. Agr. Exp. Sta. Research bul. 25. 
(3) Eckles, C. H. 1916. The nutrients required to develop the bovine fetus. 
Mo. Agr. Exp. Sta. Research bul. 26. 
(4) Foebes, E. B., with collaborators. 1914. The metabolism of organic and 
inorganic compounds of phosphorus. Ohio Agr. Exp. Sta., Tech. ser. 
bul. 6, p. 66. 
(5) Foebes, E. B., with collaborators. 1916-1918. The mineral metabolism of 
the milch cow. Ohio Agr. Exp. Sta. Buls. 295, 308, and 330. 
