Vle CONG. INTERN. REPROD. ANIM. INSEM. ARTIF., PARIS, 1968, VOL. I

Investigations Concerning the Occurrence of Early
Embryonic Death (E.e.d.) in the Mare.

R. Moberg, Dept. Obst. & Gynec., Coll. Vet. Med.,
Haut jdrvi, Finland & L. Rauvala, State Horse Breed-
ing Inst., Ypdajd, Finland.

Although E.e.d. has long been considered a major
cause of infertility in the mare (among others, Williams,
Caslick, Day, Berthelon, Miller, Nishikawa), there is
surprisingly little exact information on this subject.
Since 1963, the authors have been conducting regular
examinations of the sexual health of the breeding stock
at the S.H.B. Inst., with special regard to the occur-
rence of E.e.d.

Material. The breeding stock of the S.H.B. Inst. as well
as privately-owned mares brought there for breeding pur-
poses. The horses were exclusively of the Finnish draught
horse breed. They were fed ample rations of hay and oats
during the stabling period and kept on good pasture to
graze in the summer and given adequate supplements of
mineral-mixture, of Iodine per evaporation, and of wvita-
mins A,D, and E. They were also tested for endo-para-
sites three times a year and, if necessary, treated.

Methods. The mares were examined weekly throughout the
breeding season, starting in late March-early April and
ending in November. Pregnancy was diagnosed rectally,
starting 3 weeks, usually 4 to 5 weeks, after service.
A confirmative examination was performed 10 weeks after
service.

Results. Table 1.

The occurrence of early embryonic death during six
breeding seaspons at the State Horse Breeding Insitute.
The figures for the years 1963-64 concern only the ma-
res considered risks regarding E.e.d.

 

Year Number Pregnant E.e.d. E.e.d.? % % of est.
of mares cases

1963 7 3 2 1

1964 9 7 3 1

1965 48 26 4L 2 23l 154
1966 L1 26 L 1 1952 15.4
1967 39 24 L 1 18%5 14.8
1968 37 25 2 L 24,0 8.0

 

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