Retrospective study on the efficacy of hCG in an equine artificial insemination programme using frozen semen

摘要

In the last few years, European horse breeders have used frozen semen more intensively. The per cycle pregnancy rate obtained with equine frozen semen is generally lower(40% vs. 60-70%) than that achieved with fresh or cooled semen (Jasko 1992). For most stallions, this reduced fertility with frozen semen is true in spite of the more intense reproductive management applied to mares inseminated with frozen/thawed spermatozoa(Pace and Sullivan 1975; Pickett et al.1987; Brinsko and Varner 1992; Jasko 1992).