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.

Improvement of Boar Semen Quality by Sperm Selection Using Magnetic Nano-particles

“…than those collected from low fertile males [9,14]. In many agricultural and clinical laboratories, routine practices of semen quality analyses for artificial insemination purpose are often limited to the evaluation of sperm concentration and proportion of motile spermatozoa due to the rapidity of the tests, but these parameters are still relatively poor predictors of semen fertility [5,9].…”

“…In many agricultural and clinical laboratories, routine practices of semen quality analyses for artificial insemination purpose are often limited to the evaluation of sperm concentration and proportion of motile spermatozoa due to the rapidity of the tests, but these parameters are still relatively poor predictors of semen fertility [5,9]. The aforementioned viability factors have tremendous impact on the fertility of spermatozoa during their progression within the female genital tract and their interactions with eggs at the site of fertilization [6,11,14], but their evaluation can be laborious and results are often available after the preparation of insemination doses. Although current available tests can be effective at quantifying the proportions of viable spermatozoa within semen ejaculates or doses for artificial insemination [8], the removal of damaged spermatozoa would be of great add-on.…”

Effect of seasonal infertility period on boar sperm proteins and quality characteristics

“…These results can influence the seasonal reproductive differences in a farm, since VSL is correlated with the total number of live born piglets (Broekhuijse et al, 2012). Lee et al (2014) proposed that VSL should be considered to select semen for AI. Although LIN is not a sensitive indicator of sperm motion, Hirai et al (2001) found a higher non-return to estrus rate in boars with significantly higher LIN.…”

Lectin-Functionalized Magnetic Iron Oxide Nanoparticles for Reproductive Improvement

“…Most importantly, semen normally contains a heterogeneous population of spermatozoa with attributes that have a significant impact on male fertility potential [6,7]. For example, semen collected from normal fertile males usually results in significantly low proportions of abnormal spermatozoa and higher proportions of motile spermatozoa, with better viability (i.e., intact acrosome, plasma and mitochondrial membranes, low DNA fragmentation index) than those collected from low fertile males [8,9]. In many agricultural and clinical laboratories, routine practices of semen quality analyses for artificial insemination purpose are often limited to the evaluation of sperm concentration, motility, and morphology due to the rapidity of the tests.…”

“…Yet, these parameters are relatively poor predictors of semen fertility [1,10]. In contrast, the aforementioned viability factors are strong predictors of semen fertility due to their tremendous impacts on sperm progression within the female genital tract and interaction with the oocyte at the site of fertilization [9,11,12]; however, their evaluation can be laborious and results are often only available after the preparation of insemination doses. Although current available tests can be effective at quantifying the proportions of viable spermatozoa within semen ejaculates or doses for artificial insemination [13], the removal of damaged spermatozoa would be of great benefit.…”