Effects of fermented water hyacinth meal on blood, serum indices and gut microbiome in Hy-Line Brown hens

The escalating cost of soybean meal in poultry diets and the ecological and economic burden of water hyacinth (Eichhornia crassipes), which cost African nations over US$100 million annually in control and fisheries losses have driven interest in water hyacinth meal as a sustainable alternative feed ingredient. This study scientifically evaluated the effects of dietary fermented water hyacinth meal (FWHM) on blood haematology, serum biochemical indices and the gut microbiome composition in Hy-Line Brown laying hens over a 63-day feeding trial. No significant differences (p > 0.05) were detected in blood haematological and serum biochemical parameters across treatment groups, indicating that FWHM inclusion up to 5% did not impair bird health and nutrition status. FWHM significantly modulated the gut microbiota, resulting in reduced populations of Escherichia coli (1.83 ± 0.04 × 106 CFU/mL in control vs. 1.35 ± 0.05 × 106 CFU/mL in 5% FWHM, p < 0.001) and Staphylococcus aureus (2.68 ± 0.5 × 104 CFU/mL in control vs. 1.40 ± 1.7 × 104 CFU/mL in 2.5% FWHM), accompanied by an increase in yeast populations (0.00 CFU/mL in control vs. 2.5 ± 5.0 × 104 CFU/mL in 2.5% FWHM and 2.7 ± 1.7 × 104 CFU/mL in 5% FWHM-treated groups). These findings position FWHM as a potential feed ingredient in poultry, influencing gut microbiota while maintaining physiological homeostasis.