title: Effect of different freezing velocities on the quality and fertilising ability of cryopreserved rabbit spermatozoa.
abstract: The freezing step of the cryopreservation protocol negatively influences the quality and fertilising ability of rabbit spermatozoa. This study determines the effect of different rates of freezing on the quality and fertilising ability of rabbit spermatozoa cryopreserved with dimethylsulfoxide (DMSO) (1.75M) and sucrose (0.05M). Ejaculates from meat rabbit line males (n=12) were pooled and each pool (n=7) was split into four aliquots. One group of straws (control, C) was frozen in static liquid nitrogen vapour (5cm above the liquid nitrogen, 10min) and the other groups were frozen at different freezing rates (°Cmin(-1)) from -6°C to -100°C using a programmable freezer: slow (-15°Cmin(-1), S), medium (-40°Cmin(-1), M) or fast (-60°Cmin(-1), F). After thawing (50°C, 12s), the quality was highest (P<0.05) in C and M samples and lowest in S and F samples. F samples presented the lowest litter sizes (P≤0.05) and fertility whilst M samples exhibited the highest values. In conclusion, the freezing rate affects both the quality and the fertilising ability of frozen-thawed rabbit spermatozoa, with both slow (-15°Cmin(-1)) and fast (-60°Cmin(-1)) freezing rates being detrimental for the quality and fertilising ability.
authors.affiliation: Centro de Tecnología Animal - Instituto Valenciano de Investigaciones Agrarias (CITA-IVIA), Polígono La Esperanza, 100. Apdo. 187. 12400 - Segorbe (Castellón), Spain.
authors.forename: E
authors.initials: E
authors.lastname: Mocé
authors.affiliation: Centro de Tecnología Animal - Instituto Valenciano de Investigaciones Agrarias (CITA-IVIA), Polígono La Esperanza, 100. Apdo. 187. 12400 - Segorbe (Castellón), Spain.
authors.forename: E
authors.initials: E
authors.lastname: Blanch
authors.affiliation: Centro de Tecnología Animal - Instituto Valenciano de Investigaciones Agrarias (CITA-IVIA), Polígono La Esperanza, 100. Apdo. 187. 12400 - Segorbe (Castellón), Spain.
authors.forename: A
authors.initials: A
authors.lastname: Talaván
authors.affiliation: Centro de Tecnología Animal - Instituto Valenciano de Investigaciones Agrarias (CITA-IVIA), Polígono La Esperanza, 100. Apdo. 187. 12400 - Segorbe (Castellón), Spain.
authors.forename: M P
authors.initials: MP
authors.lastname: Viudes de Castro
mesh_terms: D000818:Animals; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents / Q000494:pharmacology*; D005298:Fertility / Q000187:drug effects*; D008297:Male; D011817:Rabbits; D012662:Semen Preservation / Q000379:methods*; D013081:Sperm Motility / Q000187:drug effects; D013094:Spermatozoa / Q000187:drug effects*
chemical_list: D003451:Cryoprotective Agents