Effect of fortification of extender with α‐terpineol and rosemary essential oil on post‐thaw ovine semsen quality

Abstract

The goal of the present study was to assess the viability of the cryopreserved ovine (Ovis aries) semen, upon supplementation with α-terpineol and rosemary essential oil (Rosmarinus officinalis). The collection of the semen from six rams formed the pool, collected once a week during 7 weeks. The diluted semen was packed into straws (0.25 ml) and frozen in a TK 3000® device. Both α-terpineol and rosemary essential oil were added in the concentrations of 6.25, 12.5 and 25 μg/ml to the TRIS-yolk extender forming six experimental groups; the control group received only the TRIS-yolk extender. The samples were analyzed after thawing regarding motility and vigor, integrity of the plasmatic membrane, thermoresistance test (TT), mitochondrial membrane potential, acrosomal integrity and computer-assisted semen analysis (CASA). The levels of the thiobarbituric acid reactive substances were also analyzed. According to the results obtained with the addition of the concentrations of 6.25, 12.5 and 25 μg/ ml of α-terpineol, significantly reduced the parameters assessed through CASA (VSL, LIN and WOB) and TT. Rosemary essential oil did not have deleterious effects on the spermatozoa and did not reduce the oxidative stress in the concentrations studied, although it presented absolute values higher than those of the control in several parameters. Alpha-terpineol in the concentrations studied was not able to reduce the oxidative stress and had toxic effect over the ovine spermatozoa.

Recent approaches in the use of antioxidants and proteomic modifications in ram semen preservation

“…Motlagh et al (2014) found that a 2% rosemary extract in the ram semen extender improved sperm parameters and reduced MDA levels. Bezerra et al (2022) discovered that a 12.5 μg/mL concentration of rosemary extract increased sperm motility, improved membrane integrity at 25 μg/mL, and enhanced acrosome integrity at 6.25 μg/mL after thawing. Moreover, Diab et al (2021) demonstrated that the use of 20 mg of rosemary extract in the ram semen extender at 37 and 5°C improved motility, live sperm count, and reduced abnormality rates.…”