Objective: Aging roosters typically exhibit subfertility with decreasing semen quality, furthermore Thai native roosters reared in rural areas are raised for a longer duration than their usual lifespan. The present study therefore aimed to assess the effect of selenium supplementation as an antioxidative substance in diets to improve the semen cryopreservation of aged roosters.Methods: Semen samples were collected from young (n = 20) and aged (n = 20) Thai native roosters (Pradu Hang Dum) at 36 and 105 weeks of age when starting the experiment, respectively. They were fed diets either non-supplemented or supplemented with selenium (0.75 ppm). Fresh semen quality and lipid peroxidation of fresh semen was evaluated before cryopreservation using the traditional liquid nitrogen vapor method. Post-thaw sperm quality and fertility potential were determined.Results: Advancing age is unrelated to decreasing fresh semen quality (p>0.05). However, lipid peroxidation in rooster semen depended on age, and the malondialdehyde (MDA) concentration increased in aged roosters (p<0.05). Selenium supplementation in diets significantly decreased the MDA concentration and increased the sperm concentration (p<0.05). In contrast, cryopreserved semen was affected by advancing rooster age, and selenium influenced sperm quality (p<0.05). Younger roosters had higher post-thaw sperm quality and fertility potential than aged roosters (p<0.05). Likewise, diet selenium supplements improved post-thaw sperm quality and fertility compared with the non-supplement group.Conclusion: Rooster’s age does not influence the rooster sperm quality of fresh semen, while sperm cryotolerance and fertility were greater in young roosters than in aged roosters. However, sperm of aged roosters could be improved by dietary selenium supplementation.

Objective: Semen cryopreservation result in decreased sperm parameters and fertilization ability. Sericin exhibits antioxidant activity by reducing lipid peroxidation resulting from free radicals, which can potentially improve cryopreservation outcomes. The present study aimed to examine the efficacy of various sericin concentrations supplemented with a rooster semen-freezing extender on post-thaw semen quality and fertilizing ability of sperm after cryopreservation.Methods: Semen samples were collected from 40 roosters (5 reps), then were pooled, and divided into four groups by the levels of sericin supplementation (0%, 0.25%, 0.50%, and 0.75%) in a freezing extender. Semen suspensions were loaded in medium straw (0.5 mL) and cryopreserved with the traditional liquid nitrogen vapor method. Post-thawed semen was evaluated for sperm motility, sperm viability, and lipid peroxidation. Also, the fertility test was determined.Results: The results showed that supplementation of the freezing extender with 0.50% to 0.75% sericin resulted in greater total motility and progressive motility and lower malondialdehyde levels than the other groups after cryopreservation (p<0.05). However, the viability of 0.75% decreased compared with the value of 0.50% sericin supplementation (p<0.05). Moreover, the fertility and hatchability of total eggs were significantly higher in the 0.50% sericin group than in the other groups (p<0.05).Conclusion: In conclusion, 0.50% sericin is recommended as an alternative component of the freezing extender to improve cryopreserved rooster semen.

This study evaluated the effect of semen extenders and antioxidant supplementation strategies on the quality and fertility of Thai native rooster semen during cold storage. In Experiment 1, four extenders (EK, IGGKPh, NaCl, and NCAB) were evaluated for their ability to preserve sperm motility, viability, lipid peroxidation (MDA), and oxidative stress (reactive oxygen species; ROS) over 24 h at 5°C. EK and IGGKPh extenders yielded superior motility (68.72% and 70.27%) and viability (91.96% and 91.97%) while minimizing MDA (0.93 and 1.12 µmol) and ROS (14.44% and 14.04%) compared to NaCl (motility: 53.14%, viability: 82.09±3.15, MDA: 1.59 µmol; P < 0.01). Experiment 2 examined the effects of dietary selenium (0.6 ppm), extender-based glutathione (GSH) supplementation (2mM), and their combination across all extenders. Antioxidant treatments, particularly GSH and its combination with selenium, improved motility, viability, and oxidative stability (P < 0.05). At 24 h, GSH-enriched groups using EK and IGGKPh exhibited enhanced motility (67.90% and 71.49%) compared to the controls (57.97% and 55.09%). In the NaCl group, GSH and combined treatments significantly improved motility at 12 h (50.83% and 50.01%, respectively) compared to the control (40.80%; P < 0.01). Selenium also increased sperm concentration (4.24 ± 0.55 × 10⁹ vs. 2.46 ± 0.22 × 10⁹ spz/mL; P < 0.01). Experiment 3 fertility outcomes using EK extender and the same antioxidant treatments from Experiment 2. Fertility rates were significantly higher in the GSH (70.38%) and combined (69.16%) groups than in the control (54.26%; P < 0.01), while hatchability remained unaffected (P > 0.05).In summary, the composition of the extender and antioxidant strategy has a significant influence on semen quality and fertility. The EK and IGGKPh extenders, especially when supplemented with GSH, offered superior protection, and combining dietary selenium with GSH yielded synergistic benefits for semen preservation and reproductive success.

The conventional method of ovarian superstimulation requires multiple injections of gonadotropins which is time-consuming and may be stressful for the cows. This study was designed to determine whether a single epidural injection of FSH (EI group) would induce the superovulatory response in the Thai-Holstein crossbreed and evaluate FSH plasma hormone concentrations. Eight cows (replication = 3; n=24) were assigned to one of 2 treatments in switch back design. Control group (n=12): cows were received 400 mg FSH twice daily by intramuscularly for 4 days (80, 80, 60, 60, 40, 40, 20 and 20 mg), EI group (n=12): cows were received 400 mg FSH by single epidural injection. Data were collected in term of ovarian follicle responses, superovulatory responses, ova/embryo collection. FSH concentrations were examined using ELISA. The total follicular responses during oestrus were not different between treatments; however, the large follicles were less frequent (P < 0.01) while the medium follicle sizes were higher (P < 0.05) in the EI group. The plasma concentration of FSH in EI was dramatically increased within 2 hours before decreasing sharply thereafter (P < 0.01) and did not remain above baseline after 10 hours of administration. The embryo quality was better in the control than the EI groups (P < 0.05). Interestingly, the number of ovulation cysts in the EI group was 50%. The ovarian responses and embryo quality in the cows with cysts were worse compared with the non-cyst groups (P < 0.05). In conclusion, alternative protocols decreased the superovulatory response and increased poor embryo quality in Thai-Holstein crossbred. Also, the incidence of ovarian follicular cysts is higher in the EI group.

Boar sperm are highly sensitive to oxidative and cold-induced stress during storage, which compromises their functional integrity. This study evaluated the dose-dependent effects of L-serine, an amino acid involved in glutathione synthesis and membrane stabilization, on boar sperm quality under chilled (17 °C) and cryopreserved conditions. Ejaculates from fertile boars were extended with Modena-based media supplemented with 0, 1, 3, 5, and 7 mM L-serine. Sperm quality parameters, including motility, viability, mitochondrial activity, acrosome integrity, lipid peroxidation (measured by malondialdehyde (MDA)), and antioxidant enzyme activity, were assessed over five days for chilled semen and post-thaw for cryopreserved samples. L-serine at 3 mM was most effective in maintaining chilled semen quality, as evidenced by superior motility, viability, and acrosome integrity by Day 5, accompanied by lower MDA levels and increased glutathione peroxidase and catalase activities. In contrast, 1 mM was optimal for cryopreserved semen, improving post-thaw motility, mitochondrial activity, and antioxidant defense while reducing lipid peroxidation. Higher concentrations (≥5 mM) consistently impaired sperm function, likely due to osmotic stress or redox imbalance. These findings indicate that L-serine enhances boar sperm preservation in a concentration- and method-specific manner, with 3 mM supplementation most effective for chilled storage, and 1 mM for cryopreservation. This study supports the inclusion of amino acid antioxidants in extender formulations to improve semen preservation in swine artificial insemination systems.

This study investigated the effects of coenzyme Q10 (CoQ10) supplementation on in vitro oocyte maturation, lipid peroxidation, and embryonic development in prepubertal and aging Thai–Holstein cows. First, we used slaughterhouse-derived oocytes to confirm that CoQ10 (50 μM) significantly enhanced cleavage (53.33% vs. 37.50%) and blastocyst formation rates (46.81% vs. 27.50%). Thereafter, oocytes were collected from four prepubertal and four aging cows via ovum pick-up and matured in vitro with or without CoQ10 supplementation. The follicular development and oocyte quality were assessed. Aging cows exhibited significantly more follicles (24.00 vs. 16.67) and greater oocyte recovery (16.67 vs. 11.67) than prepubertal cows. Additionally, CoQ10 supplementation significantly reduced malondialdehyde levels in aging cows (1.28 vs. 0.61 nmol/mL), indicating reduced lipid peroxidation. Finally, CoQ10 significantly improved cleavage rates in both age groups (prepubertal: 22.50 to 32.50%; aging: 41.71 to 65.00%) and blastocyst formation rates in aging cows (prepubertal: 17.50 to 20.00%; aging: 31.44 to 53.72%). These results suggest that CoQ10 supplementation enhances oocyte maturation and embryonic development, particularly in aging cows, likely by mitigating oxidative stress and supporting mitochondrial function. Therefore, CoQ10 may be a valuable supplement in assisted reproductive technologies for improving reproductive efficiency in cattle breeding programs.