V. R.
RAJAGOPALAN
419
introduced into the stud farm. Therefore, the parentage of the various brood
mares was examined as well as that of the stallions used for covering. It
was found that there was no definitely constant factor which appeared to be
responsible for these abortions. But of twelve mares that had aborted, seven
had been covered by Ragazzo. The records of service show that this
stallion was most frequently used during the previous season (40 per cent. of
the services), and the incidence of abortions with the increased use of ' Ra-
gazzo ' introduces a factor of some importance which is dealt with later.
There are reports in literature [Magnusson, 1935] that abortion may be due
to deficiency of minerals particularly calcium. The normal rate of abortion in
the farm prior to 1929 was from four to seven per year. In 1929 the autho-
rities introduced the " churn " brand of mineral flour with a view to improve
the bone of their young stock. This product is issued by the Imperial
Chemical Industries Ltd., and is said to contain iron, calcium, sodium chloride,
phosphorus, sulphur, potassium and iodine. During 1930, the abortions
were reduced to two. During 1931, 1932 and 1933 there were no abortions and
in 1934 there was one abortion. This mineral supplement was stopped in
March 1934. In 1935 there were two abortions and in 1936 twelve abortions
up to the month of May. The introduction and withdrawal of mineral
supplement in this stud coincided exactly with the disappearance and reap-
pearance of abortions in this herd. Citrated blood and blood sera were
therefore collected for mineral estimation, and a calcium deficiency was detect-
ed. Whereas the normal calcium content of the serum of mares should be
from 11 to 13 mgm. per 100 c. c., the calcium content of the serum of the mares
at Ahmednagar ranged from 7.7 to 8.7 mgm. per 100 c. c.
There is recorded experimental evidence to show that a total deficiency
in vitamin E may lead to sterility. Recently, Moussu [1935] has claimed to
have demonstrated that deficiency in vitamin E predisposes animals to abor-
tion due to infection with Brucella abortus, although Gillain [1937] has failed
to substantiate this claim. This dietetic factor is said to be available in
abundance in the green plants of the graminaciae. As these animals were
getting oats, which is also rich in vitamin E, deficiency in this vitamin can
presumably be ruled out in this case and as the animals were given fifteen
pounds of lucerne daily there could be no deficiency in vitamin A.
DISCUSSION
From the above record, it is evident that S. abortus equi, the common
cause of contagious abortion in mares, has not been involved in this outbreak
of abortion. On the other hand, Str. pyogenes and Esch. coli were recoverable
from a certain percentage of cases. Although some strains of these have been
found to be virulent in the laboratory for small animals, it has not been possible
to assign to them a role of primary significance as they were not met with
in the majority of cases [Miessner and Koser 1934, Dimock and Edwards
1932]. It is, however, possible that in those cases in which they occurred
they may have had a secondary pathological significance. A strong case,
M