Quercetin improves immune function in Arbor Acre broilers through activation of NF-κB signaling pathway

Area of Science:

• Immunology
• Animal Nutrition
• Poultry Science

Background:

• Quercetin, a key flavonoid, possesses diverse biological activities and stable chemical properties, making it suitable for feed additives.
• Enhancing poultry immune function is crucial for improving flock health and productivity, with functional feed additives offering a promising approach.

Purpose of the Study:

• To investigate the effects of dietary quercetin on the immune function and regulatory mechanisms in Arbor Acre broilers.
• To establish optimal quercetin supplementation levels for functional feed additives in poultry.

Main Methods:

• 240 Arbor Acre broilers were fed diets containing 0, 0.02, 0.04, or 0.06% quercetin for 6 weeks.
• Evaluated growth performance, immune organ indices (spleen, thymus, bursa), serum immune molecules, T lymphocyte proliferation, and immune-related gene expression.

Main Results:

• Quercetin did not significantly affect broiler growth performance.
• 0.06% quercetin increased spleen and thymus indices and elevated levels of immunoglobulin A (IgA), interleukin-4 (IL-4), immunoglobulin M (IgM), complement component 4 (C4), and tumor necrosis factor-α (TNF-α).
• Higher quercetin levels (0.04% and 0.06%) upregulated immune genes (TNF-α, TRAF-2, TNFRSF1B, NF-κBp65, IFN-γ) and downregulated IκB-α, indicating activation of the NF-κB pathway.

Conclusions:

• Dietary quercetin effectively modulates immune function in broilers, with optimal effects observed at 0.06%.
• Quercetin enhances broiler immunity by activating the TNF-α-triggered NF-κB signaling pathway.
• Quercetin shows potential as a functional feed additive for improving poultry immune health.