Chemically defined caseinate extenders and their effect on the cooled semen collected from stallions with long sexual rest

The ability of three milk-based extenders to preserve the motility and viability cooled shipped semen produced by stallions after a long sexual rest was evaluated. In total, 21 ejaculates from 11 were collected 5–6 months inactivity diluted with Kenney, INRA 96, EquiPlus. Seven parameters evaluated – spermatozoa (VIT, %), total (MOT, progressive (PMOT, number per ml (prog M/ml, million/ml), average path velocity (VAP, μm/s), curvilinear (VCL, μm/s) straight-line (VSP, μm/s). These determined CASA 2 hours processing then in 24, 48 72-hour intervals storage at 5 °C. effect time highly significant (P<0,001) for all parameters. extender (P<0.05) VIT, MOT, PMOT, VCL, VSL VAP. extended 96 reached significantly (P<0.01) higher values compared Kenney extender. increased VCL VAP EquiPlus (P<0.05). observed extenders, MOT VIT decreased linearly whereas PMOT exponentially. fastest decrease within 24 storage. results obtained using showed that quality period can be sufficiently maintained during least