oct. is, 1925 Calcium Phosphate as Supplement to Dairy Raiion 
789 
Relatively, each group has produced about the same proportion of 
vigorous and good calves. The mineral group has had a somewhat 
higher proportion of fair calves, while the nonmineral group has had 
relatively almost twice as many delicate ones. The deaths at birth 
and the abortions probably have no bearing on the experiment, but 
are presented in order that the statistics may. be complete. It is 
perhaps significant that there have been a relatively large number of 
delicate calves from the nonmineral group. The weakness of con¬ 
stitution has manifested itself for the most part in a very delicate 
and sensitive digestive system. All of these delicate calves had to 
be pampered along, not even making satisfactory progress on a whole 
milk-skim milk diet, and in the end every one of them died or had to 
be killed. Post-mortem examination revealed in every instance more 
or less inflammation of the digestive tract, amounting in at least one 
case to a chronic gastrointestinal* catarrh. 
It would be unwise, however, to attach too much weight to this 
evidence, for other factors, such as the individuality and breed of 
the dams, has no doubt had considerable to do with the condition of 
the calves. All the vigorous-and good calves have been from Holstein 
cows. All the fair ana delicate ones, with four exceptions, have been 
from Jersey cows. Three of the four exceptions were heifer’s calves, 
and were mot sired bv a Holstein bull. . . 
SUMMARY 
The object of this experiment has been to test the efficacy of 
adding supplemental inorganic salts of calcium to the rations of clairy 
cows. 
The whole station herd has been fed for two and a half years on a 
ration decidedly low in calcium, too low, from the standpoint of our 
E resent knowledge, for the needs of the animals. One-half of the 
erd has had the deficiency made good theoretically by supplementing 
the ration with calcium phosphate in the form of special steamed 
bone meal. 
The following are the outstanding facts revealed by the investiga¬ 
tion thus far: 
(1) Irrespective of the group to which they belong, the experimental 
procedure has had no prolonged ill effects on the general condition 
of the aged cows, of the young Holstein cows, or of the heifers, but 
has apparently seriously disturbed the metabolism of the young 
Jersey cows. 
(2) Changes in body weight of the aged cows have been insigni¬ 
ficant. Obviously, the young cows and heifers can not be considered 
under this heading. 
(3) Milk production has not been significantly affected either by 
the low-calcium ration or by the mineral supplement, except in the 
case of the young Jersey cows. They have not milked as freely or 
as persistently as it was expected they would. Too much stress, 
however, should not be placed upon this latter statement, because 
of the small number of cows studied. 
(4) With the possible exception of calcium, the composition of the 
milk has not been appreciably effected. 
(5) The reproductive function has been more seriously disturbed 
than any other, considerable difficulty being experienced in getting 
