The impact of varying doses of moringa leaf methanolic extract supplementation in the cryopreservation media on sperm quality, oxidants, and antioxidant capacity of frozen-thawed ram sperm.

To increase rams' post-thaw semen quality following cryopreservation, this study used enriched Tris-based diluent with varying amounts of moringa leaf methanolic extract (MLME). The antioxidant activity, total phenolic, and total flavonoid content were all assessed in MLME. The sperm of five healthy Awassi rams were collected, divided into 4 equal aliquots, and diluted [1:5; (v/v)] in Tris-citrate-glucose extender supplemented with 0.48, 0.56, and 0.64 mg MLME/ml or without MLME supplementation (control). The percentages of sperm total motility (STM, %), sperm progressive motility (SPM, %) and viability (V, %), abnormal morphology (AM, %), membrane functional integrity (MFI, %), and acrosome integrity (AI %) were measured. Malondialdehyde (MDA), nitric oxide (NO), ascorbic acid (AA), superoxide dismutase (SOD), glutathione peroxidase (GPx), total cholesterol (TC), low-density lipoproteins (LDL), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), zinc (Zn), and copper (Cu) were measured. The total phenolic gallic acid and flavonoid catechin (equivalent) contents were 19.78 mg/g and 11.94 mg/g, respectively. 2,2-Diphenyl-1-picrylhydrazyl (34.37 mM TE/g) and 2,2'-azino-bis/3-ethylbenzothiazoline-6-sulfonic acid (53.47 mM TE/g) were found in MLME. MLME had a 64.59 mM TE/g ferric-reducing power. In comparison to control, the addition of 0.64 mg/ml MLME to Tris-based extender resulted in the highest (P < 0.001) STM (55.22 ± 0.98), SPM (45.41 ± .70), SV (60.01 ± 1.05), MFI (75.23 ± 0.77), and AI (73.13 ± 0.72) and the lowest (P < 0.001) AM (21.34 ± 0.72) values. In comparison to the control, the addition of 0.56 mg/ml semen extender resulted in lower STM, SPM, SV, MFI, and AI with higher AM percentages. MDA (P = 0.03), NO (P = 0.012), CHO (P = 0.0001), and LDL (P = 0.004) were reduced by 0.64 mg/ml MLME, while AA (P = 0.017) and SOD (P = 0.0001) were elevated. In conclusion, the highest copper (P = 0.006) and lowest zinc concentrations in MLME (0.48 mg/ml extender) deteriorated the post-thaw semen quality, prompting us to suggest the addition of 0.64 mg MLME to rams' Tris-based semen extender.

Supplemental dietary zinc sulphate and folic acid combination improves testicular volume and haemodynamics, testosterone levels and semen quality in rams under heat stress conditions.

This study was aimed to investigate the combined effect of zinc sulphate and folic acid (ZnF) dietary supplementation on testicular haemodynamics (TH), testicular volume (TV), plasma testosterone levels (T) and semen quality of rams under heat stress conditions. Fifteen Ossimi rams were allocated to three groups: (1) G0 (n = 5) received only basic diet; (2) G1 (n = 5) received basic diet +ZnF (Zn, 0.4 mg/kg bw; F, 0.02 mg/kg bw) and (3) G2 (n = 5) received basic diet +ZnF (Zn, 0.8 mg/kg bw; F, 0.04 mg/kg bw) daily for 60 days. TH was evaluated using colour (testicular coloration, TC) and spectral modes [resistive index (RI) and pulsatility index (PI)] Doppler of the supra-testicular arteries (proximal and distal parts, STA). Semen traits including progressive motility (PM), alive sperm % (AS), sperm viability (SV), sperm abnormalities (SA) and acrosome integrity (AI) were also assessed. The examinations were carried out one month before (D-30), the beginning of ZnF inclusion in the diet (D 0) and continued for the successive two months (D 30 and D 60). TH was significantly (p < .05) improved at D 30 and D 60, evidenced by lowering both RI and PI and increasing of TC in G1 compared to G0 and G2. In addition, both TV and serum T levels were elevated (p < .05) at D 30 and D 60 in G1 compared to other groups. Semen quality parameters (PM, AS, SV and AI) were significantly (p < .05) augmented in the same trend as TH, TV and T in G1 versus G0 and G2. A marked decrease (p < .05) in SA % was noticed at Days 30 and 60 after ZnF inclusion in G1 compared to G0 and G2. In conclusion, supplementation of the summer diet with ZnF improved the whole reproductive functions such as testicular haemodynamics and semen quality of rams housed in heat stress conditions.

Melatonin can improve viability and functional integrity of cooled and frozen/thawed rabbit spermatozoa.

Melatonin is known to protect sperm against freezing-inflicted damage in different domestic species. The aim of the study was to evaluate the effect of supplementation of semen extender with melatonin on the quality and DNA integrity of cooled and frozen/thawed rabbit spermatozoa. We also investigated whether the addition of melatonin to the semen extender could improve the fertility of rabbit does artificially inseminated with frozen/thawed semen. Semen samples collected from eight rabbit bucks were pooled and then diluted in INRA-82 supplemented either with (0.5, 1.0 or 1.5 mM) or without (0.0 mM) melatonin. Diluted semen was cooled at 5°C for 24 hr. For cryopreservation and based on the first experiment's best result, semen samples were diluted in INRA-82 in the presence or absence of 1.0 mM melatonin and then frozen in 0.25 ml straws. Following cooling or thawing, sperm quality and DNA integrity were evaluated. Furthermore, the fertility of frozen/thawed semen was investigated after artificial insemination. Supplementation of semen extender with 1.0 mM melatonin improved (p < .05) motility, viability, membrane and acrosome integrities in cooled semen compared with other groups. Sperm quality and DNA integrity were higher (p < .05) in frozen/thawed semen diluted in 1.0 mM melatonin-supplemented extender than in the control group. Conception and birth rates were higher in does inseminated with 1.0 mM melatonin treated semen compared with the controls. In conclusion, supplementation of semen extender with 1.0 mM melatonin improved the quality of cooled and frozen/thawed rabbit spermatozoa. Melatonin can preserve DNA integrity and enhance the fertility of frozen/thawed rabbit spermatozoa.

Impact of supplementation of semen extender with antioxidants on the quality of chilled or cryopreserved Arabian stallion spermatozoa.

The aim of the present study was to evaluate the effects of supplementation of semen extender with various non-enzymatic antioxidants on the quality of cooled or cryopreserved Arabian stallion spermatozoa. Semen collected from four pure Arabian stallions was centrifuged at 600g for 15 min. Spermatozoa were then diluted in INRA-82 extender supplemented with bovine serum albumin (BSA; 0, 10, 15 and 20 mg/mL) or trehalose (0, 75, 100 and 150 mM) or zinc sulphate (0, 100, 150 and 200 µM). The diluted semen was then either cooled at 5 °C or cryopreserved in 0.5-ml plastic straws. After cooling or thawing, sperm motility, viability, sperm abnormalities, viability index, and plasma membrane integrity were evaluated. The results showed that supplementation of semen extender with 150 mM trehalose or with 200 µM zinc sulphate significantly (P < 0.05) improved motility, viability, sperm membrane integrity and acrosome status in Arabian stallion spermatozoa after cooling or after freezing and thawing compared with controls (non-supplemented media) or with those supplemented with other concentrations of trehalose or zinc sulphate. Supplementation of semen extender with BSA did not improve sperm motility or cryosurvival of Arabian stallion spermatozoa after cooling or after freezing and thawing. In conclusion, supplementation of semen extender with non-enzymatic antioxidants (trehalose or zinc sulphate) improved the quality of chilled and frozen/thawed Arabian stallion spermatozoa. The most beneficial effects occur when semen diluent was supplemented with 150 mM trehalose or 200 µM zinc sulphate.