To the best of our knowledge, this study is the first to determine the effect of ginseng as an antioxidant supplement in freezing extenders on the quality of cryopreserved rooster semen. Semen samples were collected from 40 Thai native roosters (Pradu Hang Dum) using the dorso-abdominal massage method and then pooled and divided into five groups according to the concentrations of ginseng supplementation (0, 0.25, 0.50, 0.75, and 1 mg/mL) in a freezing extender. The semen suspensions were loaded into a medium straw and cryopreserved using the liquid nitrogen vapor method. The post-thaw semen was evaluated for sperm quality (sperm motility and membrane integrity), seminal plasma characteristics (lipid peroxidation, superoxide dismutase [SOD], catalase [CAT], and glutathione peroxidase [GPx]), and fertility. The results showed that ginseng extract supplementation at 0.25 mg/mL yielded the highest total motility, progressive motility, and membrane integrity (59.47%, 30.82%, and 48.30%, respectively; p < 0.05) in cryopreserved rooster semen. Higher malondialdehyde concentrations were observed in the control group than in the other groups (p < 0.05). SOD, CAT, and GPx increased compared with those in the control group (p < 0.05). The results showed that the fertility rate with 0.25 mg/mL of ginseng was higher than that of the control group (62.80% vs. 46.28%: p < 0.05). In conclusion, supplementation with 0.25 mg/mL of ginseng is recommended as an alternative component to the freezing extender to improve rooster semen cryopreservation.

Cooled semen storage methods result in oxidative stress generated by an imbalance between oxidation rates, specifically reactive oxygen species production, and sperm cell antioxidants, leading to degradation of semen quality. We aimed to investigate the impact of adding Eurycoma longifolia (EL) extract as an antioxidant supplement in semen storage medium (IGGKPh semen extender) on semen quality and fertility potential. EL extract at concentrations of 5, 10, 15, and 20 mg/mL was assessed for its antioxidant capacity in IGGKPh semen extender. Our findings revealed that the total phenolic content in the EL extract did not vary significantly across the various concentrations and temperatures tested. However, incubation at 5°C was found to be the most effective temperature for increasing the EL extract antioxidant capacity as assessed via the 2,2-diphenyl-1-picrylhydrazyl inhibition assay in a dose-dependent manner. Supplementation of the IGGKPh semen extender with 15 mg/mL EL extract was found to enhance semen quality during cold storage for up to 48 h (p < 0.05), as evidenced by decreased malondialdehyde levels in cooled semen (p < 0.05). However, antioxidant enzyme activities showed no significant differences among the various experimental groups (p > 0.05). The fertility test showed that the 15 mg/mL EL extract group stored for 24 h had a higher percentage than the control group (p < 0.05). However, there was no significant difference in percentage between the two groups at 48 h of storage (p > 0.05). The hatchability showed no significant difference in both 24 and 48-h storage periods (p > 0.05). Our results indicated that supplementing the IGGKPh semen extender with 15 mg/mL EL extract may positively influence semen quality during storage, suggesting potential applications for enhancing semen quality.

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.

Grandparent roosters are crucial in poultry breeding programs and significantly influence future bird generations' genetic makeup and performance. However, these roosters face considerable challenges from heat stress, which can adversely affect their reproductive performance, semen quality, and overall health and welfare. Our study aimed to investigate the effects of heat stress on the genetics of semen characteristics, identify the appropriate temperature and humidity indices (THI), and determine the threshold point of heat stress to prevent thermal stress. We analyzed data from 3,895 records of 242 Thai native grandparent roosters in conjunction with the THI using 7 THI functions and the regression method. The threshold point of heat stress, genetic parameters, rate of decline of semen characteristics per level of THI, estimated breeding values and selection index values were analyzed using the multivariate test-day model in the AIREML and BLUPF90 programs. Based on the regression coefficient and statistical criteria of the lowest -2logL and AIC values, the results showed that a THI of 78 was considered the threshold point of heat stress. The estimated heritability values ranged from 0.023 to 0.032, 0.066 to 0.069, 0.047 to 0.057, and 0.022 to 0.024 for mass movement, semen volume, sperm concentration, and the semen index, respectively. The reduction rates of mass movement, semen volume, sperm concentration, and semen index at a THI of 78 were -0.009, -0.003, -0.170, and -0.083 per THI, respectively. The genetic correlations among the semen traits were moderately to strongly positive and ranged from 0.562 to 0.797. The genetic correlations between semen traits and heat stress were negative and ranged from -0.437 to -0.749. The permanent environmental correlations among the semen traits (0.648-0.929) were positive and greater than the genetic correlations. Permanent environmental correlations between semen traits and heat stress were negative and ranged from -0.539 to -0.773. The results of the selection indices showed that the higher the selection intensity was, the greater the degree to which the selection index corresponded to genetic progress. The recommendation for animal genetic selection is that the top 10% is appropriate because it seems most preferred. Therefore, using a multivariate test-day model and selection index for the high genetic potential of semen traits and heat tolerance in Thai native grandparent roosters makes it possible to achieve genetic assessment in a large population.

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.