Purified Dietary Aflatoxin B1 Does Not Impair Broiler Growth Across a Broad Exposure Range but Elicits Subclinical Biological and Tissue Responses

Aflatoxin B1 (AFB1) toxicity in poultry is often investigated using naturally contaminated ingredients, which can confound its effects with co-occurring mycotoxins and changes in feed quality. Male Arbor Acres broilers received a common basal diet supplemented with purified AFB1 at nominal concentrations of 0, 5, 10, 20, 50, 100, or 200 μg/kg for 42 d. The reported analyses detected no significant treatment differences in growth performance or major organ indices. Hepatic antioxidant enzyme activities and total antioxidant capacity decreased at selected exposures, while serum antioxidant enzymes, cytokines, and hematological indices showed selective responses. Jejunal villus height was lower in the nominal 50–200 μg/kg groups. Renal tubular lesions were most evident at 50–100 μg/kg. Bile-acid profiling in four selected groups showed compartment-specific differences. These findings suggest that selected biological and morphological responses may occur without detectable growth impairment under the conditions tested. Isolated biomarker differences remain exploratory, and the data do not establish a formal ranking of endpoint sensitivity or a dietary safety threshold.