title: Conventional slow freezing cryopreserves mouflon spermatozoa better than vitrification.
abstract: This work examines the effectiveness of a TCG (Tris, citric acid, glucose, 6% egg yolk and 5% glycerol) and a TEST (TES, Tris, glucose, 6% egg yolk and 5% glycerol) sperm extender in the freezing of mouflon spermatozoa at slow cooling rates, using different pre-freezing equilibration times (2-3 hr). It also examines the tolerance of mouflon spermatozoa to different concentrations of cryoprotectants (5, 10, 20% glycerol; 5%, 10%, 20% dimethyl sulfoxide; 6% polyvinylpyrrolidone) and/or sucrose (100, 300, 500 mm). The highest quality (p < .01) thawed spermatozoa were obtained when using the TEST extender and an equilibration time of 3 hr. Sperm motility and membrane integrity were strongly reduced when using rapid freezing rates (60-85°C min-1), independent of the concentration of cryoprotectants. The lowest sucrose concentration (100 mm) provided the highest (p < .05) percentage of motile spermatozoa and live spermatozoa with an intact acrosome. Vitrified-warmed sperm variables were at their best when the spermatozoa was diluted in TCG-6% egg yolk + 100 mm sucrose and warmed at 60°C. Slow warming at 37°C strongly reduced (p < .05) sperm motility and viability. However, sperm vitrification returned lower fertility, sperm motility and sperm viability values than conventional sperm freezing.
authors.affiliation: Departamento de Reproducción Animal, INIA, Madrid, Spain.|Conselho Nacional de Desenvolvimento Cientifico e Tecnológico - Cnpq, Brasilia, Brasil.
authors.forename: J
authors.initials: J
authors.lastname: Pradiee
authors.affiliation: Departamento de Reproducción Animal, INIA, Madrid, Spain.
authors.forename: M C
authors.initials: MC
authors.lastname: Esteso
authors.affiliation: Departamento de Reproducción Animal, INIA, Madrid, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Castaño
authors.affiliation: Departamento de Reproducción Animal, INIA, Madrid, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Toledano-Díaz
authors.affiliation: Departamento de Reproducción Animal, INIA, Madrid, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Lopez-Sebastián
authors.affiliation: Zoológico de Córdoba, Ayuntamiento de Córdoba, Córdoba, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Guerra
authors.affiliation: Departamento de Reproducción Animal, INIA, Madrid, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Santiago-Moreno
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D019343:Citric Acid / Q000494:pharmacology; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary*; D003451:Cryoprotective Agents / Q000494:pharmacology*; D005615:Freezing; D005947:Glucose / Q000494:pharmacology; D005990:Glycerol / Q000494:pharmacology; D008297:Male; D011407:Propane / Q000031:analogs & derivatives / Q000494:pharmacology; D012662:Semen Preservation / Q000662:veterinary*; D034561:Sheep, Domestic; D013081:Sperm Motility / Q000187:drug effects*; D013094:Spermatozoa / Q000187:drug effects*; D013395:Sucrose / Q000494:pharmacology; D013451:Sulfonic Acids / Q000494:pharmacology; D013997:Time Factors; D014325:Tromethamine / Q000494:pharmacology; D058989:Vitrification
chemical_list: C586115:2-((1,3-dihydroxy-2-(hydroxymethyl)propan-2-yl)amino)ethanesulfonic acid; D003451:Cryoprotective Agents; D013451:Sulfonic Acids; D014325:Tromethamine; D019343:Citric Acid; D013395:Sucrose; D005947:Glucose; D005990:Glycerol; D011407:Propane
keywords: conventional freezing; cryopreservation; spermatozoa; ultra-rapid freezing; vitrification