title: Pig Spermatozoa Defect in Acrosome Formation Caused Poor Motion Parameters and Fertilization Failure through Artificial Insemination and In vitro Fertilization.
abstract: The selection of morphologically normal spermatozoa is critical to obtain high breeding performances in boar breeding farms and artificial insemination (AI) centers. Parameters for the selection of semen mainly include total sperm motility, concentration, and morphology. However, these primary parameters are often not reliable for discriminating between normal and abnormal, non-fertilizable spermatozoa. The present study was designed to compare the motion characteristics, fertilization ability using in vitro fertilization (IVF), and acrosome formation of the semen from boars having low (boar number 2012) and normal (boar number 2004 and 2023) breeding performances. The ultimate goal was to identify additional simple and easy criteria for the selection of normal sperm. There was no significant difference between boar 2004 and boar 2023 sperm total motility in computer assisted sperm analysis. However, boar number 2012 semen presented a significantly reduced population of rapid moving spermatozoa and an increased population of slow moving spermatozoa compared to boar numbers 2004 and 2023. Analysis of detailed motion characteristics revealed that sperm from boar number 2012 had significantly reduced motility in progressiveness, average path velocity, straight-line velocity (VSL), curvilinear velocity (VCL), straightness, and linearity. The assessment of the fertilizing ability by IVF also showed that sperm from boar number 2012 showed a fertility rate of 3.4%, whereas sperm from boar number 2023 had a fertility rate of 75.45%. Interestingly, most of the sperm nuclei were found on the peripheral area of the oocytes, suggesting that the sperm from boar number 2012 lacked penetration ability into the oocyte zonapellucida. The acrosome formation analysis using Pisum sativum agglutinin staining demonstrated that the sperm from boar number 2012 had a defect in acrosome formation. Consequently, primary parameters for selecting semen before AI such as motility are not sufficient to select normal and fertilizable spermatozoa. In conclusion, the present study suggests that the acrosome staining and detailed motion characteristics such as progressiveness, VCL, and VSL should be included in determining semen quality together with primary parameters for successful AI and high breeding performance in the swine industry.
authors.affiliation: Department of Animal Science, College of Agriculture, Chungbuk National University, Choung-ju 361-763, Korea .
authors.forename: Won Young
authors.initials: WY
authors.lastname: Lee
authors.affiliation: Department of Animal Science, College of Agriculture, Chungbuk National University, Choung-ju 361-763, Korea .
authors.forename: Ran
authors.initials: R
authors.lastname: Lee
authors.affiliation: Department of Animal Science, College of Agriculture, Chungbuk National University, Choung-ju 361-763, Korea .
authors.forename: Hee Chan
authors.initials: HC
authors.lastname: Kim
authors.affiliation: Department of Animal Science, College of Agriculture, Chungbuk National University, Choung-ju 361-763, Korea .
authors.forename: Kyung Hoon
authors.initials: KH
authors.lastname: Lee
authors.affiliation: Department of Animal Science, College of Agriculture, Chungbuk National University, Choung-ju 361-763, Korea .
authors.forename: Xiang Shun
authors.initials: XS
authors.lastname: Cui
authors.affiliation: Department of Animal Science, College of Agriculture, Chungbuk National University, Choung-ju 361-763, Korea .
authors.forename: Nam Hyung
authors.initials: NH
authors.lastname: Kim
authors.affiliation: R&D Team, Darby Genetics Inc. Anseong 456-915, Korea .
authors.forename: Sang Hyun
authors.initials: SH
authors.lastname: Kim
authors.affiliation: R&D Team, Darby Genetics Inc. Anseong 456-915, Korea .
authors.forename: Il Joo
authors.initials: IJ
authors.lastname: Lee
authors.affiliation: Department of Animal Science and Biotechnology, Sangji Youngseo College, Wonju 220-713, Korea .
authors.forename: Sang Jun
authors.initials: SJ
authors.lastname: Uhm
authors.affiliation: Department of Horse, Companion and Wild Animal Science, College of Animal Science, Kyungpook National University, Sangju 742-711, Korea .
authors.forename: Min Jung
authors.initials: MJ
authors.lastname: Yoon
authors.affiliation: Department of Animal Science, College of Agriculture, Chungbuk National University, Choung-ju 361-763, Korea .
authors.forename: Hyuk
authors.initials: H
authors.lastname: Song
keywords: Acrosome Defect; Boar; In vitro Fertilization; Motion Parameters; Sperm