title: Improved cryopreservation protocol for Blanca-Celtibérica buck semen collected by electroejaculation.
abstract: The collection of sperm samples by electroejaculation (EE) leads to an increase of the production of seminal plasma which could modify the tolerance of spermatozoa to the cryopreservation procedure. This study aims to compare a standard sperm cryopreservation protocol for samples collected by artificial vagina (AV) with the same protocol and modifications to this for samples obtained by EE. Semen from six males of Blanca-Celtibérica goat breed was collected by AV (control) and EE, and three experiments were conducted. In Experiment 1, it was examined the effects of egg yolk concentration contained in freezing extender (0%, 1.5%, 10% and 20% of egg yolk); in Experiment 2, it was evaluated the cooling rate from 30 to 5 °C (fast: 10 min and slow: 90 min) and the temperature of glycerol addition (30 and 5 °C); and in Experiment 3, it was examined the time of equilibration at 5 °C (0, 1, 2 or 3h). A heterologous in vitro fertilization test was carried out in order to compare the fertility of control samples with that resulting from the EE protocol which showed the highest sperm quality. Results showed greater sperm motility parameters after thawing for control samples cryopreserved in standard conditions in the three experiments. For samples collected by EE, extender with 20% egg yolk, a slow cooling rate and a longer equilibration time (3h) provided higher sperm quality, and no differences were observed between temperatures of glycerol addition. Samples collected by EE and cryopreserved with the protocol which yielded the best sperm quality after thawing showed higher fertility compared to AV.
authors: Regional Center of Animal Selection and Reproduction (CERSYRA) JCCM, 13300 Valdepeñas, Spain.
authors: Pilar
authors: P
authors: Jiménez-Rabadán
authors: Manuel
authors: M
authors: Ramón
authors: Olga
authors: O
authors: García-Álvarez
authors: Alejandro
authors: A
authors: Maroto-Morales
authors: Pablo J
authors: PJ
authors: Alvaro-García
authors: Enrique
authors: E
authors: Del Olmo
authors: M Dolores
authors: MD
authors: Pérez-Guzmán
authors: M Rocio
authors: MR
authors: Fernández-Santos
authors: J
authors: J
authors: Julián Garde
authors: Ana J
authors: AJ
authors: Soler
mesh_terms: D000818:Animals; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary*; D003451:Cryoprotective Agents / Q000378:metabolism; D004530:Egg Yolk / Q000378:metabolism; D005260:Female; D005307:Fertilization in Vitro; D005990:Glycerol / Q000378:metabolism; D006041:Goats / Q000502:physiology*; D008297:Male; D012661:Semen / Q000166:cytology / Q000187:drug effects; D012662:Semen Preservation / Q000379:methods / Q000662:veterinary*; D013048:Specimen Handling / Q000379:methods / Q000662:veterinary*; D013081:Sperm Motility / Q000187:drug effects; D013094:Spermatozoa / Q000166:cytology / Q000187:drug effects
chemical_list: D003451:Cryoprotective Agents; D005990:Glycerol
keywords: Blanca-Celtibérica buck; Cooling rate; Egg yolk; Electroejaculation; Equilibration; Glycerol