Different concentrations of cysteamine and ergothioneine improve microscopic and oxidative parameters in ram semen frozen with a soybean lecithin extender.

The aim of this study was to evaluate the effects of ergothioneine and cysteamine as antioxidant supplements in a soybean lecithin extender for freezing ram semen. Twenty-four ejaculates were collected from four rams and diluted with extenders (1.5% soybean lecithin, 7% glycerol) containing no supplements (control) and cysteamine or ergothioneine (2, 4, 6 or 8mM). Motility by CASA, viability, plasma membrane functionality (HOS test), total abnormality, lipid peroxidation, glutathione peroxidase (GPx) activity and capacitation status (CTC staining) were assessed after thawing. Using 6mM of either antioxidant improved total motility. Cysteamine at 6mM and ergothioneine at 4 and 6mM improved viability and reduced lipid peroxidation (malondialdehyde concentration). Both antioxidants improved membrane functionality significantly, except at 8mM. Progressive motility, kinematic parameters, GPx activity, capacitation status and sperm abnormalities were not influenced by the antioxidant supplements. In conclusion, cysteamine at 6mM and ergothioneine at 4 or 6mM seem to improve the post-thawing quality of ram semen cryopreserved in a soybean lecithin extender.

Effect of quercetin loaded liposomes or nanostructured lipid carrier (NLC) on post-thawed sperm quality and fertility of rooster sperm.

The aim of this study was to investigate the effects of 10, 15 and 20 µM quercetin, alone or loaded in nanoliposomes or in nanostructured lipid carrier (NLC) on sperm rooster cryopreservation and fertility performance. Sperm motility, viability, abnormalities, membrane integrity, mitochondrial activity, apoptosis status, lipid peroxidation (LP), GPX, SOD, TAC and fertility and hatchability rate were investigated after freeze-thawing. A significantly higher percentage (P < 0.05) of sperm total motility was obtained in sperm cryopreserved with 15 µM quercetin loaded NLC compared to diluent with 10 and 20 µM quercetin and to 10, 15 and 20 µM quercetin loaded nanoliposomes, 20 µM quercetin loaded NLC and control group. Also, 15 µM quercetin loaded NLC was significantly higher in progressive motility, VSL, VAP and VCL parameters compared to control group. The percentage of viability, membrane integrity, mitochondria activity, TAC, and GPx increased in semen exposed to 15 µM quercetin loaded NLC group. Likewise, the lowest level (P < 0.05) of malondialdehyde (MDA) was acquired in samples treated with 15 µM quercetin and quercetin loaded NLC group in comparison to the control group. Abnormal form, SOD, and early apoptosis were not (P > 0.05) affected by different levels of quercetin. Fertility and hatchability rate showed higher levels in 15 µM quercetin and quercetin loaded NLC group compared with control group. In conclusion, it seems that quercetin loaded NLC enhanced the antioxidant effect of quercetin by improving post-thawed sperm quality and fertility of rooster sperm.

Effects of adding different levels of Glutamine to modified Beltsville extender on the survival of frozen rooster semen.

The aim of the present study was to investigate the effects of l-glutamine on the quality of frozen-thawed rooster semen. Semen samples were collected from eight mature roosters (Ross 308). After initial semen assessments, samples of adequate quality were mixed together and diluted with modified Beltsville extender without l-glutamine (control) and supplemented with 2.5, 5, and 7.5mM l-glutamine. Semen straws were subjected to cryopreservation and evaluated twice at 15-day intervals. After thawing, sperm viability, total and progressive sperm motilities were measured by Eosin-Nigrosine and Computer-Aided Sperm Analysis (CASA), respectively. The results showed that sperm functions decreased on day 30 compared to day 15. The extender supplemented with 5mM glutamine improved (p<0.05) sperm viability, total and progressive sperm motilities compared to other treatments and the control group. The best level of glutamine appeared to be 2.5mM, as it provided the highest sperm membrane integrity and the lowest level of abnormalities. The results of this study suggest that the addition of glutamine to the diluent improves semen quality and using glutamine allows rooster sperm to be frozen for longer.