DIETARY AQUEOUS GARLIC (ALLIUM SATIVUM) SUPPLEMENTATION MODULATES REPRODUCTIVE HORMONAL PROFILES IN NIGERIAN INDIGENOUS COCKS

Abstract

This study investigated the dose-dependent effects of aqueous garlic (Allium sativum) supplementation on the reproductive hormonal profile of Nigerian indigenous cocks, a valuable genetic resource adapted to tropical environments. Thirty-six mature cocks were randomly assigned to four treatment groups receiving 0 (control), 5, 10, and 15 g/L garlic in drinking water (designated T1–T4 respectively), with three replicates per treatment and three birds per replicate, in a completely randomized design. Blood samples were collected at the end of the 6-week experimental period for serum analysis of testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) using standard enzyme-linked immunosorbent assay (ELISA) procedures. Results revealed significant (P < 0.05) differences in testosterone concentrations among treatment groups, with birds receiving moderate garlic supplementation (T2: 5 g/L) exhibiting the highest testosterone levels (3.87 ± 0.15 ng/mL), representing a 28.1% increase over controls (3.02 ± 0.11 ng/mL). Birds receiving 10 g/L garlic (T3) maintained elevated testosterone (3.61 ± 0.12 ng/mL), while the highest inclusion level (T4: 15 g/L) resulted in testosterone concentrations (2.94 ± 0.10 ng/mL) comparable to controls and significantly lower than T2 and T3. Serum LH and FSH concentrations showed no significant differences (P > 0.05) across treatments, although numerical improvements were observed at moderate supplementation levels. These findings demonstrate that moderate garlic supplementation (5–10 g/L) enhances testosterone production in Nigerian indigenous cocks, likely through the antioxidant and bioactive properties of garlic's organosulfur compounds, particularly allicin. However, excessive garlic inclusion (15 g/L) may exert inhibitory effects on testicular endocrine function, consistent with previous reports of dose-dependent reproductive toxicity in male animals. The study provides evidence-based recommendations for the strategic use of garlic as a natural phytogenic supplement to enhance reproductive performance in indigenous poultry breeding systems, with an optimal dosage range of 5–10 g/L in drinking water.