Parquetina nigrescens leaf extract mitigates aflatoxin B1-induced stress, immune and growth disruptions in broilers.

Aflatoxin B₁ (AFB₁) contamination in poultry feed impairs immunity, induces oxidative stress, and reduces growth and carcass quality. This study assessed the protective role of Parquetina nigrescens leaf extract (PNLE) against AFB₁-induced immuno-inflammatory, oxidative, and metabolic disturbances in broiler chickens. Two hundred day-old Cobb 500 broiler chicks were assigned to four groups: NOC (control), AFCP0 (AFB₁ only, 0.5 mg/kg feed), AFCP1 (AFB₁ + 1 g PNLE/L water), and AFCP2 (AFB₁ + 2 g PNLE/L). AFB₁ exposure (AFCP0) significantly reduced relative growth rate (RGR), dressing percentage, and catalase activity, while increasing liver and spleen weights, lipid/protein peroxidation, and pro-inflammatory cytokines (IL-6, TNF-α, IL-1β). Immunoglobulins (IgG, IgM, IgA), triiodothyronine (T₃), and leptin levels were suppressed, with elevations in Hsp70 and adiponectin. PNLE, particularly at 2 g/L, significantly improved antioxidant status, immune response, inflammatory balance, and performance metrics. Correlation analysis revealed strong positive associations between RGR and IgM (r = +0.84) and IgA (r = +0.65), and negative correlations with IL-1β (r = -0.72) and IL-6 (r = -0.61). Dressing percentage correlated positively with IgG, IgM, IgA, and IFN-γ, but negatively with TNF-α, IL-6, and IL-1β (p < 0.01). These findings underscore the relevance of immune competence and inflammation control in broiler productivity. In conclusion, PNLE mitigates AFB₁-induced toxicity and supports health and performance. A supplementation level of 2 g/L in drinking water is recommended as a practical strategy to reduce aflatoxicosis risk in poultry production.