Density gradient centrifugation of frozen-thawed equine semen with low motility and fertility.

none6Stallions are not selected for fertility, and breeders can demand the use of frozen semen of high valuable stallions despite a poor quality after thawing.The aim of this study was to verify if density gradient centrifugation of low quality frozenthawed semencanimprove sperm quality and fertility rates after deep horn uterine insemination. Low quality frozen-thawed semen, recovered from one stallion with a breeding report of no pregnancy, was centrifuged on a discontinuous density gradient. Sperm recovery rate, motility and membrane integrity were assessed.Four mares were inseminated for two consecutive cycles with low dose-low volume deep horn technique. Sperm quality and viability was improved after gradient centrifugation, but any of the mares became pregnant after insemination.mixedMari G; Mislei B; Rizzato G; Dardi M; Iacono E; Merlo BMari G; Mislei B; Rizzato G; Dardi M; Iacono E; Merlo