Effect of dietary nickel chloride on splenic immune function in broilers

Area of Science:

• Poultry immunology
• Toxicology
• Environmental health

Background:

• Dietary trace minerals are crucial for poultry health.
• Nickel chloride (NiCl2) is a source of nickel, a metal with potential toxic effects.
• Understanding NiCl2's impact on avian immunity is vital for animal welfare and production.

Purpose of the Study:

• To investigate the effects of varying dietary NiCl2 levels on broiler splenic immune function.
• To quantify changes in cytokine expression, immunoglobulin levels, and immune cell populations.
• To determine the threshold of NiCl2 supplementation that causes detrimental effects.

Main Methods:

• Quantitative reverse transcription polymerase chain reaction (qRT-PCR) for mRNA expression.
• Enzyme-linked immunosorbent assay (ELISA) for immunoglobulin quantification.
• Flow cytometry (FCM) for immune cell subset analysis.

Main Results:

• Dietary NiCl2 supplementation (300, 600, 900 mg/kg) significantly decreased mRNA and protein levels of key cytokines (IL-2, IL-6, IL-10, IL-12, TNF-α/LITAF, IFN-γ).
• Immunoglobulin (IgA, IgG, IgM) contents were significantly reduced in NiCl2-treated groups compared to controls.
• A notable reduction in T-cell subsets and IgA+ B cell numbers was observed in broilers fed excess NiCl2.

Conclusions:

• Dietary nickel chloride at levels exceeding 300 mg/kg causes significant damage to splenocytes and impairs splenic immune function in broilers.
• These findings highlight the potential toxicity of elevated NiCl2 in poultry diets.
• Further research into the specific mechanisms of NiCl2 toxicity on splenic immunity is warranted.