Injectable antibiotics reprogram the gut microbiota-immune-resistome axis in ducks before detectable changes in...

Area of Science:

• Veterinary Medicine
• Microbiology
• Immunology

Background:

• Injectable antibiotics are widely used in poultry production.
• Their use can disrupt gut microbiota and host immune function.
• This may promote antimicrobial resistance and affect nutrient utilization.

Purpose of the Study:

• To assess the effects of six common injectable antibiotics on ducks.
• Evaluated impacts on gut microbiota, host immunity, tissue accumulation, and antimicrobial resistance.
• To understand subclinical effects and associated risks in poultry production.

Main Methods:

• Systematic evaluation of six injectable antibiotics in ducks over 28 days.
• Analysis of feed conversion ratio, organ indices, and antibiotic tissue accumulation (ELISA).
• 16S rRNA sequencing for gut microbiota analysis and identification of antibiotic resistance genes (ARGs).

Main Results:

• Antibiotic exposure altered microbiota-organ associations and restructured the gut microbiota, decreasing E. coli and enriching Gram-positive taxa.
• Antibiotic residues were detected in muscle tissues, with some persisting through day 28.
• Drug-specific ARGs and altered immune gene expression (cytokines IL-6, IL-10, TNF-α) were observed.
• An integrative network highlighted conserved associations between microbiota, immunity, residues, and ARGs.

Conclusions:

• Injectable antibiotics cause coordinated changes in host-microbiota-resistance interactions before observable growth impacts.
• Findings provide a framework for evaluating antibiotic risks in poultry.
• Highlights the need for careful antibiotic use in intensive poultry farming.