Effects of skim-milk supplementation on the quality and penetrating ability of boar semen after long-term preservation at 15 °C

Abstract

This study investigated the effects of skim-milk supplementation on the quality and penetrating ability of boar semen preserved at 15 °C. When boar semen samples were preserved in Modified Modena extender supplemented with various concentrations (0, 7.5, 15, 30 and 50 mg/mL) of skim milk powder at 15 °C for 4 weeks, higher sperm motility and viability were observed in the case of 7.5 mg/mL skim-milk supplementation compared with the control group (0 mg/mL) during the preservation (P < 0.05). When in vitro matured oocytes were co-incubated with boar sperm that had been preserved in Modified Modena extender with three different concentrations (0, 7.5 or 15 mg/mL) of skim milk powder at 15 °C for two weeks, there were no apparent effects of skim-milk supplementation on the rates of fertilisation and development to blastocysts of oocytes after co-incubation. However, the monospermic fertilisation rate of sperm preserved with 15 mg/mL skim milk powder was higher (P < 0.05) than that of fresh non-preserved sperm, but did not differ among the preservation groups. The results indicate that the supplementation of Modified Modena extender with 7.5 mg/mL skim milk powder improves the motility and viability, but not the penetrating ability, of sperm after liquid preservation for at least two weeks.

Effects of chlorogenic acid and caffeic acid on the quality of frozen‐thawed boar sperm

“…Semen collection and cryopreservation were performed according to the method described by Namula et al () and Karja et al () with minor modifications, respectively. In brief, semen samples were collected once from five fertile Large White boars (2–3 years old) by the gloved‐hand technique in November 2017.…”

“…Semen collection and cryopreservation were performed according to the method described by Namula et al (2014)…”

A mechanism by which Astragalus polysaccharide protects against ROS toxicity through inhibiting the protein dephosphorylation of boar sperm preserved at 4 °C

“…In addition, because of the limited ability of sperm to establish a powerful defense system of antioxidants, a great deal of effort has been invested to search for exogenous antioxidants to prevent oxidative damage (Zhang et al, 2017). In general, enzymatic antioxidants (such as superoxide dismutase, catalase, and glutathione peroxidase) and non-enzymatic antioxidants (such as ascorbic acid, α-tocopherol, taurine, and cysteine) provide effective defense mechanisms for sperm (Namula et al, 2014). Indeed, previous studies have indicated that adding antioxidant agents to bull (Tvrda et al, 2016), ram (Zhao et al, 2017), goat (Shafiei, Forouzanfar, Hosseini, & Esfahani, 2015), boar (Gadani, Bucci, Spinaci, Tamanini, & Galeati, 2017), canine (Setyawan et al, 2016), and human (Azadi, Tavalaee, Deemeh, Arbabian, & Nasr-Esfahani, 2017) semen can protect sperm from ROS attack and improve sperm quality parameters (Bansal & Bilaspuri, 2010).…”

Effects of Tris (hydroxymethyl) aminomethane on the quality of frozen-thawed boar spermatozoa

“…During the process of freezing and thawing, the occurrence of lipid peroxidation caused by the accumulation of ROS and the removal of natural antioxidants in the seminal plasma could severely damage the lipid tails in the sperm plasma membrane, leading to undesirable effects on spermatozoa functions and their penetrability (Bansal and Bilaspuri, 2010). In a previous study, we reported that the supplementation of skim milk powder to the semen extender improves the motility and viability of boar sperm after long-term liquid preservation (Namula et al, 2014). Skim milk has been considered to be a non-enzymatic antioxidant that functions by the sulphhydryl groups (Bustamante Filho et al, 2009).…”