Effect of different media additives on capacitation of frozen–thawed ram spermatozoa as a potential replacement for estrous sheep serum

Abstract

Capacitation is a key process through which spermatozoa acquire their fertilizing ability. This event is required for the successful application of assisted reproductive technologies such as IVF. The aim of the present study was to investigate the effect of using a synthetic oviductal fluid medium supplemented with either heparin-hypotaurine alone, in combination with progesterone (P4), 17β-estradiol (E2), or BSA, or just β-cyclodextrin, in replacement for estrous sheep serum (ESS) for ram sperm capacitation. After incubation in the corresponding media for 15 (time 0) or 60 minutes, sperm function was evaluated by computerized sperm motility analysis and flow cytometry (plasma membrane status and fluidity). Treatments rendering the best results in regards to sperm function parameters related to capacitation were used for an IVF test. Herein, neither heparin-hypotaurine (alone), or in combination with P4, or E2, nor β-cyclodextrin induced capacitation-related changes in frozen-thawed ram spermatozoa. Only the medium supplemented with heparin-hypotaurine-BSA was able to induce changes compatible with in vitro capacitation relating to sperm motility pattern and plasma membrane fluidity, comparable to those in ESS-containing medium. Both media yielded sperm parameter values that differed (P < 0.05) from those obtained in the rest of the media tested. However, after the IVF trial, BSA was unable to support cleavage rates (21.80%) comparable to those obtained with ESS (52.60%; P < 0.05). We conclude that heparin-hypotaurine, P4, E2, β-cyclodextrin, or BSA is not suitable for replacing ESS in capacitation and fertilization media for ram spermatozoa.

Oestrous sheep serum balances ROS levels to supply in vitro capacitation of ram spermatozoa

“…Recently, Garcia‐Alvarez et al. () have shown that heparin–hypotaurine, progesterone (P4), oestrogens (E 2 ), β‐cyclodextrin, or BSA are not suitable for replacing OSS in capacitation and fertilization media for ram spermatozoa. However, a cocktail of several substances, including phosphatase inhibitors, has proved highly successful (Colas, Cebrian‐Perez, & Muino‐Blanco, ).…”

Selection of red deer spermatozoa with different cryoresistance using density gradients

“…For that reason, Percoll ® has been a replacement for other products as Puresperm ® in human or Bovipure ™ in bovine species, among others. However, many authors continue to use Percoll ® for carrying out IVF with research purposes in several species (García‐Álvarez et al., , ; Schmaltz‐Panneau et al., ; Souza‐Fabjan et al., ; Van Hoeck et al., ). The main difference between these selection methods is that Puresperm ® and Bovipure ™ contain silane‐coated silica particles instead of PVP‐coated ones.…”

Effect of sexual steroids on boar kinematic sperm subpopulations

“…Effects of distinct concentrations of progesterone (0.1–100 µg/ml) and estradiol (1–100 µg/ml) has been tested on sperm motility. We previously reported the concentrations of progesterone used in this study .…”

“…Distinct approaches have been used to describe the effects of sexual steroids on sperm motility , including the use of CASA. However, until now principally mean values of motility parameters have been reported .…”

“…Distinct approaches have been used to describe the effects of sexual steroids on sperm motility , including the use of CASA. However, until now principally mean values of motility parameters have been reported . The use of only mean values to describe sperm parameters derived from CASA systems is not an appropriate approach and is of limited value .…”