Sperm subpopulations in ejaculated sperm and spermatozoa recovered from ovine epididymides up to 48 h after death

Abstract

The objectives of this study were threefold: to identify subpopulations of sperm based on the kinetics of frozen/thawed sheep epididymal spermatozoa or semen collected with an artificial vagina; to evaluate the effects on sperm subpopulations in the thawed samples of post mortem storage at room temperature and the addition of 20% of seminal plasma to the freezing extender and to correlate the percentage of subpopulations with gestation rate following artificial intrauterine insemination. The categorization of the subpopulations was based on sperm kinetic data from Computer Assisted Sperm Analysis (CASA). A hundred ewes were inseminated with thawed spermatozoa and gestation rate was correlated with the proportions of each subpopulation using Pearson correlation matrix and linear regression. Three distinct subpopulations were identified in the thawed samples of either ovine ejaculate collected in artificial vaginas (AV) or ovine spermatozoa retrieved from the cauda epididymis. Subpopulation 1 (SP1) was characterized by spermatozoa with slow and non-linear motion, subpopulation 2 (SP2) was classified as hyperactived spermatozoa and subpopulation 3 (SP3) was composed of spermatozoa with fast, linear motion. The largest subpopulation in all groups was SP1. The semen collected in an artificial vagina had a higher (P<0.05) percentage of SP2 and lower (P<0.05) percentage of SP1 when compared to spermatozoa recovered after death. Increasing time of storage after death had a detrimental effect on sperm samples, increasing (P<0.05) the percentage of SP1 and decreasing (P<0.05) SP2. Length of storage after death was the only variable that influenced, with an inversely proportional relationship, SP3. In samples stored for 48h after death no SP3 spermatozoa were present. The addition of seminal plasma to the cryopreservative decreased (P<0.05) the subpopulation of hyperactived spermatozoa (SP2). We conclude that, after thawing there are three sperm subpopulations in the spermatozoa obtained from the cauda epididymides and the semen collected in AVs and that the relative proportions of these subpopulations varies with the time of storage post mortem and the presence of 20% of seminal plasma in the extender. However, we conclude that these subpopulations do not correlate with fertility after intrauterine artificial insemination.

Effect of semen and donor factors on multiple ovulation and embryo transfer (MOET) in sheep

“…The uterine horns were visualized with a 5 mm and 30° angulated laparoscope (Karl Stroz, Tuttlingen, German). The spermatozoa were deposited into the uterine lumen in the middle of the uterine horn using an Robertson pipet (Minitube Brasil, Porto Alegre, Brazil) (Bergstein‐Galan, Weiss, Bertol, et al, ; Bergstein‐Galan, Weiss, Kozicki, & Bicudo, ).…”

Sperm subpopulations influence the pregnancy rates in cattle

“…The computer-assisted sperm analysis (CASA) allows assessing the sperm kinetics and the individual record of their trajectories (Amann & Waberski, 2014;Barbas et al, 2018;Holt & Satake, 2018), based on multivariate statistical analyses to identify and monitor the behaviour of sperm subpopulations within an ejaculate (Souza et al, 2018). The determination of sperm subpopulations based on individual sperm kinetics has been reported in animal species such as domestic cats (Gutiérrez-Reinoso & García-Herreros, 2016;Souza et al, 2018), dogs (Núñez-Martínez et al, 2006;Peña et al, 2012), stallions (Quintero-Moreno et al, 2003), donkeys (Flores et al, 2008), sheep (Barbas et al, 2018;Bergstein-Galan et al, 2017;Dorado et al, 2011;Santolaria et al, 2015), boars (Estrada et al, 2017;Flores et al, 2009), rabbits (Quintero-Moreno et al, 2007) and red deer (Martinez-Pastor et al, 2005). In bulls, studies that evaluated fresh semen and post-thawed samples identified four sperm subpopulations (Ferraz et al, 2014;Ibanescu et al, 2020;Muiño et al, 2009;Muiño, Rivera, et al, 2008;Muiño, Tamargo, et al, 2008).…”

Influência Da Inclusão Do Farelo De Arroz Integral Sobre a Temperatura Corporal De Frangos De Corte De Linhagem Caipira Pedrês

“…Com o uso da análise multivariada é possível estudar variações das subpopulações em diversas etapas do processamento espermático (ABAIGAR et al, 1999;DORADO et al, 2011;GALLEGO et al, 2015)13 for gazelle. Na Figura 4 está demonstrada a porcentagem acumulada das três subpopulações espermáticas identificadas por BERGSTEIN-GALAN et al (2017c) no sêmen coletado em AV e dos epidídimos até 48 horas após a morte.…”

“…Letras diferentes indicam diferenças significativa (P<0,05) entre grupos. Adaptado deBERGSTEIN-GALAN et al (2017c)…”

“…A partir desta hipóteseBERGSTEIN-GALAN et al (2017c) identificaram três subpopulações espermáticas com base na cinética de espermatozoides epididimários recuperados até 48 horas post mortem e no sêmen coletado em vagina artificial.Com base nas velocidades de trajeto (VAP), progressiva (VSL) e curvilinear (…”