Dietary charcoal supplementation modulates hematological, biochemical, immunological, antioxidant, and intestinal parameters in ducks

Abstract

<b>Objective:</b> This study aimed to investigate the impact of dietary charcoal supplementation on hematological and biochemical indices, immune function, antioxidant status, and intestinal histomorphology in ducks. <b>Materials and Methods:</b> A total of 144 mule ducks, aged 4 weeks, were randomly allocated into 6 experimental groups. Birds were reared under uniform conditions in floor pens and provided with a basal diet (3,000 kcal/kg ME and 20% CP) supplemented with 0.0%, 0.5%, 1.0%, 1.5%, 2.0%, or 2.5% charcoal. <b>Results:</b> Dietary inclusion of charcoal at 1.0%, 1.5%, and 2.0% significantly reduced serum creatinine (<i>p</i> = 0.049) and urea concentrations (<i>p</i> = 0.036), suggesting enhanced renal function. Additionally, ducks receiving 1.5% and 2.0% charcoal exhibited significantly lower plasma corticosterone levels (<i>p</i> = 0.045) and elevated blood glucose concentrations (<i>p</i> = 0.042) compared to the control group. No significant differences (<i>p</i> > 0.05) were observed in other serum biochemical markers (total protein, albumin, globulin, albumin-to-globulin ratio, cholesterol, aspartate aminotransferase, and alanine aminotransferase) or hematological parameters. Antioxidant capacity was significantly enhanced (<i>p</i> ≤ 0.05) in ducks fed 1.5% charcoal, except for malondialdehyde levels, which remained unaffected (<i>p</i> = 0.943). Serum immunoglobulin A concentrations and relative spleen weights were significantly higher in the 1.5% and 2.0% charcoal groups (<i>p</i> = 0.0125 and <i>p</i> = 0.0207, respectively), while IgG and IgM levels did not differ among treatments (<i>p</i> > 0.05). Moreover, charcoal supplementation at 1.5%, 2.0%, and 2.5% positively influenced the villus architecture of both the duodenum and cecum (<i>p</i> < 0.05). <b>Conclusion:</b> Dietary supplementation with up to 1.5% charcoal appears to confer physiological benefits in ducks by supporting renal function, enhancing immune and antioxidant responses, and improving intestinal morphology.