VIe CONG. INTERN. REPROD. ANIM. INSEM. ARTIF., PARIS, 1968, VOL. Il

d. occurred in the first 4-10 weeks of pregnancy, before
implantation. This is not in accordance with the find-
ings of Nishikawa (1959) who found a peak of early abor-
tions at about 5 months of pregnancy.

Late service, when ovulation has already taken place,
might lead to fertilization of aged ova, with resulting
E.e.d. before any pregnancy diagnosis is possible. The
incidence of very early E.e.d. is impossible to estima-
te but ought to be at least as high as that of the ca-
ses where pregnancy can be established by examination.

Stowe (1967) found that combined vitamin A and E
supplement significantly improved reproductive perfor-
mance in general in the marej; this should also include
E.e.d.

Furthermore, it is our impression that E.e.d. might
be more common in certain families. However, the mate-
rial is still too small to allow us to draw any conclu-
sions.

References

Amoroso, E.C. (1953). Pers. comm.

Amoroso, E.C., Hancock, J.L. & Rowlands, I.W. (1948).
Nature, 161, 355.

Day, F.T..(1940). J. Agric.Seci., 30, 24k,

Nishikawa, Y. (1959) Studies on Reproduction in Horses.
Japan Racing Ass.

Stowe, H.D. (1967). Pers. comm.

Trum, B.,P. (1950). Corn. Vet. 40, 17.

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