title: Reduction of centrifugation force in discontinuous percoll gradients increases in vitro fertilization rates without reducing bovine sperm recovery.
abstract: The objective of this study was to determine the effect of different centrifugation forces in bovine sperm separation by discontinuous Percoll gradients for in vitro fertilization IVF. The semen samples from each bull were pooled or each bull were centrifuged separately and centrifuged in discontinuous Percoll gradients (30, 60 and 90%) at different forces: F1 (9000×g), F2 (6500×g), F3 (4500×g) and F4 (2200×g), according experiment. The sperm samples were evaluated to determine the concentration, motility, vigor, morphology, reactive oxygen species (ROS), integrity of the plasma membrane, lipid peroxidation, antioxidants and embryo development were also evaluated. No difference was observed in the concentration of sperm submitted to different centrifugation forces. The total percentage of motile sperm was increased after centrifugation at F3 and F4, and the ROS production at F1 was greater than the other forces. When the bulls semen were processed individually, no significant differences were observed for the sperm quality parameters between F1 and F4, including lipid peroxidation, antioxidants, cleavage rate and average time to the first cleavage. This work demonstrated for the first time that centrifugation at 2200×g enhanced the sperm penetration and fertilization rates without reducing sperm recovery compared to the typical centrifugation force (9000×g) currently used by the commercial bovine IVF industry.
authors.affiliation: Federal University of Pampa (UNIPAMPA), BIOTECH, Lab Biotechnology of Reproduction, 97.500-970, Uruguaiana, RS, Brazil.
authors.forename: A C G
authors.initials: AC
authors.lastname: Guimarães
authors.affiliation: Federal University of Pampa (UNIPAMPA), BIOTECH, Lab Biotechnology of Reproduction, 97.500-970, Uruguaiana, RS, Brazil.
authors.forename: F G
authors.initials: FG
authors.lastname: Leivas
authors.affiliation: Federal University of Pampa (UNIPAMPA), BIOTECH, Lab Biotechnology of Reproduction, 97.500-970, Uruguaiana, RS, Brazil.
authors.forename: F W
authors.initials: FW
authors.lastname: Santos
authors.affiliation: Federal University of Pampa (UNIPAMPA), BIOTECH, Lab Biotechnology of Reproduction, 97.500-970, Uruguaiana, RS, Brazil.
authors.forename: E B
authors.initials: EB
authors.lastname: Schwengber
authors.affiliation: Federal University of Pampa (UNIPAMPA), BIOTECH, Lab Biotechnology of Reproduction, 97.500-970, Uruguaiana, RS, Brazil.
authors.forename: A B
authors.initials: AB
authors.lastname: Giotto
authors.affiliation: Federal University of Pampa (UNIPAMPA), BIOTECH, Lab Biotechnology of Reproduction, 97.500-970, Uruguaiana, RS, Brazil.
authors.forename: C I U
authors.initials: CI
authors.lastname: Machado
authors.affiliation: Federal University of Pampa (UNIPAMPA), BIOTECH, Lab Biotechnology of Reproduction, 97.500-970, Uruguaiana, RS, Brazil.
authors.forename: C G M
authors.initials: CG
authors.lastname: Gonçalves
authors.affiliation: Federal University of Pampa (UNIPAMPA), BIOTECH, Lab Biotechnology of Reproduction, 97.500-970, Uruguaiana, RS, Brazil.
authors.forename: N P
authors.initials: NP
authors.lastname: Folchini
authors.affiliation: Federal University of Pampa (UNIPAMPA), BIOTECH, Lab Biotechnology of Reproduction, 97.500-970, Uruguaiana, RS, Brazil. Electronic address: danisbrum@unipampa.edu.br.
authors.forename: D S
authors.initials: DS
authors.lastname: Brum
mesh_terms: D000818:Animals; D002417:Cattle / Q000196:embryology / Q000502:physiology*; D002499:Centrifugation, Density Gradient / Q000379:methods / Q000662:veterinary*; D005260:Female; D005307:Fertilization in Vitro / Q000662:veterinary*; D008297:Male; D018384:Oxidative Stress; D011205:Povidone; D017382:Reactive Oxygen Species / Q000378:metabolism; D055101:Semen Analysis / Q000662:veterinary; D012822:Silicon Dioxide; D013094:Spermatozoa / Q000166:cytology / Q000502:physiology*
chemical_list: D017382:Reactive Oxygen Species; C016039:Percoll; D012822:Silicon Dioxide; D011205:Povidone
keywords: Density-gradient centrifugation, Bovine, IVF; Sperm selection