title: Effect of the holding time at 15 °C prior to cryopreservation, the thawing rate and the post-thaw incubation temperature on the boar sperm quality after cryopreservation.
abstract: The aim of the present study was to evaluate the effect of the holding time at 15 °C prior to cryopreservation (2, 4 and 8h), thawing rate (37 °C for 20s or 70 °C for 8s) and post-thaw incubation temperature (15 °C or 37 °C) on the post-thaw boar sperm quality. These are important time periods in the freezing-thawing process which have been less studied. Sperm-rich ejaculate fractions from three healthy boars were collected once a week for five consecutive weeks and were cryopreserved with the lactose-egg yolk extender (LEY). Sperm quality was determined by assessing the motility, the acrosome status, and the sperm plasma membrane integrity at 30, 150 and 240 min of incubation. The results show that with the holding time at 15 °C prior to cryopreservation there was not a clear effect until at least 24h of holding time. The thawing rate and the post-thaw incubation temperature, however, had a marked effect on sperm quality. When the samples were thawed at 70 °C for 8s, the sperm viability, motility and some kinetic variables (VCL, VSL, VAP and ALH) were greater than with results observed when the samples were thawed at 37 °C for 20s. In addition after thawing the sperm samples incubated at 15 °C had a sustained sperm quality for longer, up to 4h post-thawing.
authors.affiliation: Centro de Investigación y Tecnología Animal - Instituto Valenciano de Investigaciones Agrarias (CITA-IVIA), 12400 Segorbe, Castellón, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Tomás
authors.affiliation: Centro de Pruebas de Porcino, Área de Investigación Ganadera, Subdirección de Investigación y Tecnología, Instituto Tecnológico Agrario, Consejería de Agricultura y Ganadería, Junta de Castilla y León, Ctra Riaza-Toro s/n, 40353 Hontalbilla, Segovia, Spain.
authors.forename: José
authors.initials: J
authors.lastname: Gómez-Fernández
authors.affiliation: Centro de Pruebas de Porcino, Área de Investigación Ganadera, Subdirección de Investigación y Tecnología, Instituto Tecnológico Agrario, Consejería de Agricultura y Ganadería, Junta de Castilla y León, Ctra Riaza-Toro s/n, 40353 Hontalbilla, Segovia, Spain.
authors.forename: Emilio
authors.initials: E
authors.lastname: Gómez-Izquierdo
authors.affiliation: Centro de Pruebas de Porcino, Área de Investigación Ganadera, Subdirección de Investigación y Tecnología, Instituto Tecnológico Agrario, Consejería de Agricultura y Ganadería, Junta de Castilla y León, Ctra Riaza-Toro s/n, 40353 Hontalbilla, Segovia, Spain. Electronic address: ita-merpened@itacyl.es.
authors.forename: Eduardo
authors.initials: E
authors.lastname: de Mercado
mesh_terms: D000818:Animals; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary; D008297:Male; D055101:Semen Analysis / Q000662:veterinary; D012662:Semen Preservation / Q000379:methods* / Q000662:veterinary; D013094:Spermatozoa / Q000166:cytology; D013552:Swine; D013696:Temperature; D013997:Time Factors
keywords: Boar; Holding time; Post-thaw incubation temperature; Spermatozoa; Thawing rate