Response of Boar Sperm to the Treatment with Cholesterol‐Loaded Cyclodextrins Added Prior to Cryopreservation

Abstract

Cryopreserved boar sperm is not used extensively for artificial insemination, owing to the poor fertility rates of the sperm after freezing and thawing. The sperm membrane is damaged as the cells are cooled from body temperature to 5°C (cold shock), as well as during the freeze-thaw process. Increasing the cholesterol content of boar sperm membranes could help them survive cryopreservation, similar to sperm from other species that are cold shock sensitive. The aim of this study was to determine the optimal cholesterol-loaded cyclodextrin (CLC) concentration to use for boar sperm cryopreservation, and the influence of CLCs on the cryosurvival of sperm from boars classified as good or poor freezers. Treating boar sperm with 1 mg of CLC/120 × 10(6) sperm slightly improved (p < 0.05) the percentage of viable sperm after freezing-thawing. On the other hand, sperm, from both good and poor freezers, responded similarly to CLC treatment. Nevertheless, additional studies will be needed to study the effect of this treatment on other parameters of sperm quality.

Egg Yolk and Glycerol Requirements for Freezing Boar Spermatozoa Treated with Methyl β-Cyclodextrin or Cholesterol-loaded Cyclodextrin

“…Methyl-β-cyclodextrin (MBCD) was preloaded with cholesterol, and working solutions of CLC and MBCD were prepared by mixing 50 mg of CLC or MBCD in 1 ml of BTS using a vortex mixer, in accordance with the protocol developed by Purdy and Graham [11], as described elsewhere [17]. …”

“…The ejaculates were split into 3 fractions: one fraction was untreated, and the other two were treated with 1 mg/120 × 10 6 sperm of MBCD or CLC, respectively. The treated samples were incubated with MBCD or CLC for 15 min at 22 C [17]. Thereafter, the three aliquots were cooled to 16 C over the course of 2 h.…”

Sperm cryopreservation update: Cryodamage, markers, and factors affecting the sperm freezability in pigs

“…602 improves survival of frozen-thawed mammalian sperm [193]. In the specific case of 705 pigs, the addition of CLC improves post-thaw sperm quality and in vitro fertilizing 706 ability without affecting capacitation status and DNA integrity (Table 2) [194][195][196]. The 707 main inconvenient is that adding CLC may require increasing of glycerol concentration 708 (from 3% to 5%; [197]) and this may be detrimental for sperm [46,47].…”

Effect of cyclodextrins, cholesterol and vitamin E and their complexation on cryopreserved epididymal ram semen

“…In fact, cholesterol-loaded cyclodextrins increases significantly cryosurvival of epididymal stallion semen (Pamornsakda et al, 2011) and ejaculated sperm of different animal species, including boar, goat, bull and stallion (Blanch et al, 2012;Konyali et al, 2013;Moore et al, 2005;Purdy and Graham, 2004). In Ram particularly, cyclodextrins-cholesterol complex has been reported to improve motility, viability and membrane integrity (Ahmad et al, 2013;Awad, 2011;Mocé et al, 2010;Motamedi-Mojdehi et al, 2014).…”