فهرست نشریات علمی دسترسی آزاد ایران

The Shami goat breed represents an economically important livestock resource in the Middle East, yet environmental stressors and intensive management systems can compromise reproductive performance through dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis. Ginseng (Panax ginseng C.A. Meyer), recognized for its adaptogenic properties, has shown promise in modulating stress responses and cellular protective mechanisms. This study investigated the effects of dietary ginseng powder supplementation on cortisol, adrenocorticotropic hormone (ACTH), heat shock proteins (HSP70 and HSP90), and reproductive performance parameters in Shami goat bucks. Twenty-four mature Shami bucks (2-3 years old, 45-55 kg body weight) were randomly allocated to four treatment groups (n=6 per group): control (basal diet), and three ginseng supplementation levels (1, 2, and 3 g/kg diet) for 90 days. Blood samples were collected bi-weekly for hormonal and HSP analysis. Semen quality, testicular measurements, and libido scores were evaluated throughout the experimental period. Ginseng supplementation demonstrated dose-dependent effects on HPA axis regulation. The 2 g/kg treatment group showed significantly reduced serum cortisol (32.4 ± 2.1 ng/mL vs. 48.7 ± 3.4 ng/mL in control, P < 0.01) and ACTH levels (28.6 ± 1.8 pg/mL vs. 42.3 ± 2.9 pg/mL in control, P < 0.01). HSP70 expression increased by 47% (P < 0.05) while HSP90 showed moderate elevation (23%, P<0.05) in the optimal treatment group. Sperm concentration improved from 2.8 ± 0.3 × 10⁹/mL (control) to 3.9 ± 0.2 × 10⁹/mL (2 g/kg group, P < 0.01), with corresponding improvements in motility (68.4 ± 3.2% vs. 79.8 ± 2.1%, P<0.01) and morphology.