oct. 15,1925 Calcium Phosphate as Supplement to Dairy Ration 
777 
Grain. —For the first 10 months of the experiment the grain ration 
consisted of— 
Pounds 
Ground oats__ 39 
Gluten meal_ 20 
Corn meal_ 20 
Wheat bran_ 20 
Salt_ 1 
Total_ 100 
This combination contained about 15 per cent digestible protein, 
55 per cent digestible carbohydrates and fat, 0.035 per cent calcium, 
and 0.40 per cent phosphorus. 
In October, 1922, as already noted, chopped oat straw and starch 
were substituted for a portion of the hay. As a consequence of this 
change it became necessary, in order to balance the ration, to increase 
the protein content of the grain mixture. This was done by increasing 
the gluten meal to 30 pounds per hundred, and reducing the corn 
meal to 10 pounds. The resulting grain mixture contained about 
18 per cent digestible protein, 52 per cent digestible carbohydrates 
ana fat, 0.035 per cent calcium, and 0.42 per cent phosphorus. 
The ration was again modified in September) 19%3, dried apple 
S omace being substituted for the starch, the oat straw having been 
iscontinued when the feeding of green fodder commenced in June. 
It occurred to the writers at this time (September, 1923) that possibly 
such a high percentage of gluten meal in the ration was not desirable, 
so the amount was reduced to 20 pounds, and in order to keep up the 
protein content 20 pounds of red-dog flour were substituted for the 
corn meal, so that the ration now being fed consists of: 
Pounds. 
Ground oats_ 3934 
Gluten meal_ 20 
Red-dog flour_ 20 
Wheat bran_ 20 
Salt___ % 
Total___100 
This combination contains about 17 per cent digestible protein, 53 
per cent digestible carbohydrates and fat, 0. 06 per cent calcium, and 
0.44 per cent phosphorus. 
The foregoing variations in grain and roughage have not Materially 
changed the general character of the ration, which, as already noted, 
has been formulated so as to be low in its content of calciuih and 
phosphorus. Judged according to Kellner’s {20, p . 618) standard for 
these elements, the rations have averaged throughout the experiment 
about 33 per cent deficient in calcium but have supplied a 62 per 
cent excess of phosphorus, thus showing that ordinary rations are 
much more likely to be lacking in calcium than in phosphorus, due 
to the relatively high percentages of phosphorus in all grains. 
All the cows in the herd have received this ration, and, in addition, 
one-half of the herd, known as the “mineral” group, have received 
supplemental calcium and phorphorus in the form of a steamed bone 
meal, especially prepared for animal feeding. The bone meal has 
been added to each cow’s daily grain ration at the time of weighing, 
being thoroughly mixed with the grain before feeding. The amount 
