Biosynthesis and Evaluation of Zinc, Copper, and Methionine Feed Supplements Using Saccharomyces cerevisiae on Duck Performance in Minimal Water Systems

Optimizing duck performance under minimal water conditions is essential for sustainable poultry farming. Biosynthesizing essential feed supplements like Zinc (Zn), Copper (Cu), and methionine using Saccharomyces cerevisiae presents a promising method to enhance growth and meat quality. This study developed a biosynthesis method for Zn, Cu, and methionine supplements using S. cerevisiae and evaluated their effects on duck performance. In experiment 1, substrates containing ZnO, CuSO₄, and tryptophan were fermented with varying concentrations of S. cerevisiae spores (1×10⁷, 2×10⁷ and 3×10⁷ spores/100 g) for 3, 5, 7, or 9 days. The fermentation process was assessed for physical, chemical, and biological quality to determine optimal conditions. The optimal condition was identified as 3×10⁷ spores/100 g substrate with a 9-day fermentation period, resulting in significant increases in Zn content by 25% (p<0.05), Cu content by 30% (p<0.01) and enhanced nutrient metabolism enzyme activity in ducks by 15% (p<0.05). In experiment 2, a total of 120 unsexed day-old ducks (average weight: 50 g) were randomly assigned to diets containing 2900 Kcal/kg metabolic energy and 19% protein, supplemented with 50, 100, 150, or 200 ppm of 9-octadecenoic acid methyl ester. Conducted with four replicates per treatment, supplementation with 100 ppm significantly improved feed conversion efficiency by 10% (p<0.05), body weight gain by 50 g (p<0.01), meat protein content by 5% (p<0.05) and water holding capacity by 8% (p<0.05). Sex-specific effects were not analyzed due to the use of unsexed samples. Biosynthesized Zn, Cu, and methionine supplements using S. cerevisiae effectively enhance duck performance and meat quality under minimal water conditions. Specifically, a supplementation level of 100 ppm of 9-octadecenoic acid methyl ester was optimal for improving key performance metrics.