Sire-Foal Relationships Between Harem Stallions and Foals in Misaki Horses

Abstract

1. The present investigation was conducted to determine sire-foal relationships between harem stallions and foals in Misaki horses living under conditions similar to the wild. This was done by blood typing and analyses of group formation during the breeding seasons from 1979 to 1981. 2. Almost all mares became associated with their particular stallions and these consort relationships showed a high degree of stability during the breeding season. Most mares showed a tendency to associate with the same stallions every year. 3. Paternity tests between 22 foals and 8 harem stallions by blood typings and analyses of group formation revealed that the possible sire was confined to one stallion in 15 of 22 cases, to 2 stallions in 4 cases and to 2 stallions in 3 cases, 4. The harem stallions coincided with the possible sires in 12 of 22 cases, and could be considered as possible sires in 6 cases. They could not be included among possible sires in 3 cases, and in the other case it could not be determined which stallion had associated with the dam in the previous breeding season. 5. It is generally suggested that the harem stallions are highly likely to be the foals' true sires in the groups. However, there may be cases where the true sires are not always the harem stallions with whom the dams associated during the breeding season.