A preliminary study on using autologous and heterologous boar sperm supernatant from freezing processes as post-thawing solution: its effect on sperm motility

Abstract

The aim of this study was to evaluate the effect of post-thawing dilution with autologous and heterologous sperm supernatant on motility of frozen-thawed boar spermatozoa. During the cryopreservation, sperm supernatant (a combination of seminal plasma and semen extender, 50% v/v) or seminal plasma from nine boars (Duroc, Large White, and Landrace; three in each) was collected by centrifugation and stored frozen until use as post-thawing solution. Sperm pellets were further processed and cryopreserved using control-rate freezer and was thawed at 50°C for 12 s. After thawing, frozen thawed semen samples were diluted with seminal plasma (group A), supernatant from Landrace (group B), supernatant from Large White (group C), supernatant from Duroc (group D), and Modena™ semen extender (group E). Post-thawing motility was evaluated using a phase-contrast microscope after thawing at 1, 10, 20, and 30 min. The present results show that at 1 min, a significantly higher percentage (P ≤ 0.001) of progressive motility was found in groups B (53.3%) and C (53.9%) than the other groups. At 10 min, the highest (P ≤ 0.001) progressive motility was found in groups B (65%) and C (61%). At 20 and 30 min, a significantly higher percentage (P ≤ 0.001) of progressive motility was found in groups B (58.9%), C (53.5%), and D (45.6%) than groups A (3.9%) and E (20.6%). It can be stated that supernatant from the freezing processes (consisting of seminal plasma and Modena™, 50% v/v) had a beneficial effect on post-thawing progressive motility of frozen boar semen.

Antioxidant Effects of Seminal Plasma on Cellular Morphological Viability of Swine Semen Post-Cryopreservation

“…In the present study, we found that treatment with either autologous or homologous SP resulted in higher viability rates as compared with control and, no detrimental effects when using the homologous kind. Further, our results are in agreement with those of Kaeoket et al [14] where addition of autologous or heterologous SP 50% (v/v) to extender yielded better viability as well as motility rates than in controls.…”

“…The protective effects of SP may be attributed to critical components such as antioxidant enzymes and other stabilizing proteins capable of modulating sperm function [12][13][14]. However, SP is removed prior cryopreservation to dilute the semen at a specific concentration in the extender.…”

“…Altogether, these enzymes are considered the main barrier as per sperm antioxidant protection [14] and their concentrations may not only have an effect at cryopreservation but on the overall boar fertilizing ability [3,29]. Despite some discouraging results of SP as an additive for cryopreservation, literature supporting its beneficial effects is outweighing e.g., protection against cold shock, reduction of cryocapacitation [5,6,14,15] and, improvement on the percentage of viability, motility and integrity of both plasma and acrosome membrane [23,30,31]. Recently, a seasonal variation of antioxidant activity in fluids from the vesicular glands has been reported and intriguingly, this effect is independent from the antioxidant enzyme activity of epididymal fluids [32].…”

The Fertility of Frozen Boar Sperm When used for Artificial Insemination

“…) and in the optimal ranges will have the most beneficial effect on sperm fertility at extended time intervals after thawing (Kaeoket et al. ).…”

“…It has been shown that addition of the seminal plasma from the good freezer boars to the thawing extender improves in vitro sperm fertility (Hernandez et al 2007a). The type of seminal plasma and the concentration appears important as concentrations that are too high (>50%) could damage sperm whereas when too low (<15%) may have limited to no effect (Kirkwood et al 2008) and in the optimal ranges will have the most beneficial effect on sperm fertility at extended time intervals after thawing (Kaeoket et al 2011).…”