title: Effect of different cryo-protectants on the viability of frozen/thawed semen from boars of the Piau breed.
abstract: The objective of this study was to evaluate the effect of different cryo-protectants (glycerol, dimethylacetamide and dimethylformamide alone or combined and added to lactose-egg yolk extender) on the viability of frozen/thawed semen from the Piau breed as assessed by in vitro testing. Frozen semen samples (n=20) were used from five male swine. Five different freezing extenders, including 2% glycerol (Group 1 - G), 2% glycerol and 3% dimethylacetamide (Group 2 - GA), 2% glycerol and 3% dimethylformamide (Group 3 - GF), 5% dimethylacetamide (Group 4 - A) and 5% dimethylformamide (group 5 - F), were evaluated. To assess post-thawing sperm quality, sperm motility and morphology were evaluated. Sperm viability was determined using the hypoosmotic swelling test, supravital staining, and a fluorescent assay (carboxyfluorescein diacetate and propidium iodide). The mean total sperm motility of semen immediately after thawing was 46.2±1.3, 57.7±1.5, 53.2±2.1, 51.7±1.2, and 46.5±1.6% for groups 1-5, respectively. Groups 2 (GA) and 3 (GF) had greater motility values (P<0.05). Fluorescent assay values of 22.3±2.3%, 35.2±3.7%, 30.8±3.4%, 36.6±3.7%, and 26.5±3.8% were obtained for Groups 1-5, respectively, showing that Group 4 (A) sperm had greater viability than those from Group 1 (G), although there was no differences between the other treatments (P>0.05). The other complementary tests (hypoosmotic swelling test and supra-vital staining) demonstrated that sperm in Groups 2 (GA), 3 (GF) and 4 (A) had the greatest viability and there were no significant differences among these three groups (P>0.05). The most effective cryo-protectant combinations likely minimized and controlled the deleterious processes that occur in the sperm cell during freezing/thawing, thus improving post-thawing sperm viability. In conclusion, the combination of amides (3%) and glycerol (2%) or dimethylacetamide (5%) alone were more efficient at cryo-protection than glycerol alone for semen freezing in the Piau swine breed.
authors.affiliation: Animal Science Department of Federal University of Viçosa (UFV), Brazil. Electronic address: rogerio_op@yahoo.com.br.
authors.forename: R O
authors.initials: RO
authors.lastname: Pinho
authors.affiliation: Veterinary Medicine Department of Federal University of Espírito Santo (UFES), Brazil.
authors.forename: D M A
authors.initials: DM
authors.lastname: Lima
authors.affiliation: Veterinary Medicine Department of Federal University of Viçosa (UFV), Brazil.
authors.forename: H H
authors.initials: HH
authors.lastname: Shiomi
authors.affiliation: Veterinary Medicine Department of Federal University of Espírito Santo (UFES), Brazil.
authors.forename: J B
authors.initials: JB
authors.lastname: Siqueira
authors.affiliation: Animal Science Department of Federal University of Viçosa (UFV), Brazil.
authors.forename: H T
authors.initials: HT
authors.lastname: Silva
authors.affiliation: Animal Science Department of Federal University of Viçosa (UFV), Brazil.
authors.forename: P S
authors.initials: PS
authors.lastname: Lopes
authors.affiliation: Animal Science Department of Federal University of Viçosa (UFV), Brazil.
authors.forename: S E F
authors.initials: SE
authors.lastname: Guimarães
authors.affiliation: Veterinary Medicine Department of Federal University of Viçosa (UFV), Brazil.
authors.forename: J D
authors.initials: JD
authors.lastname: Guimarães
mesh_terms: D000081:Acetamides / Q000494:pharmacology; D000818:Animals; D002470:Cell Survival; D003451:Cryoprotective Agents / Q000494:pharmacology*; D004126:Dimethylformamide / Q000494:pharmacology; D005615:Freezing; D005990:Glycerol / Q000494:pharmacology; D008297:Male; D012661:Semen / Q000187:drug effects* / Q000502:physiology; D012662:Semen Preservation / Q000379:methods / Q000662:veterinary*; D013094:Spermatozoa / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D013552:Swine / Q000502:physiology*
chemical_list: D000081:Acetamides; D003451:Cryoprotective Agents; D004126:Dimethylformamide; C013959:dimethylacetamide; D005990:Glycerol
keywords: Amides; Boars; Complementary tests; Semen