Nutrient assessment of olive leaf residues processed by solid-state fermentation as an innovative feedstuff additive

Area of Science:

• Agricultural Science
• Microbiology
• Animal Nutrition

Background:

• Olive leaf residue is a byproduct with potential for valorization.
• Solid-state fermentation (SSF) can improve the nutritional quality of agricultural byproducts.
• Feed additives are crucial for optimizing poultry growth and health.

Purpose of the Study:

• To prepare olive leaf residue feedstuff additives using SSF.
• To evaluate the effects of these additives on broiler chicken growth and health.
• To determine optimal fermentation parameters for nutrient enhancement.

Main Methods:

• Solid-state fermentation (SSF) of olive leaf residue using various mold and yeast strains.
• Co-culture fermentation with Aspergillus niger and Candida utilis for 5 days.
• Analysis of nutrient content, including amino acids and tannic acid degradation.
• Feeding trials with broiler chickens supplemented with fermented olive leaf residue.

Main Results:

• Co-fermentation with A. niger and C. utilis optimized nutrient value.
• Total amino acid content increased by 22.0%, with significant rises in Glutamic and Aspartic acids.
• Supplementation of 10% fermented residue increased chicken weight gain by 120% over 28 days.
• Improved serum biochemical parameters were observed in supplemented chickens.

Conclusions:

• SSF of olive leaf residue with A. niger and C. utilis yields a high-value feed additive.
• 10% inclusion of the fermented additive significantly promotes broiler chicken growth and development.
• Fermented olive leaf residue shows promise as a sustainable feed additive for poultry.