Effect of organic collagen peptide-chelated zinc on skin quality of meat ducks during 22∼42 days of old.

Zinc, as a cofactor for various metalloenzymes in poultry, is essential for skin integrity, immune function, and wound healing. This study optimized the synthesis conditions of organic collagen peptide-chelated zinc (oZn) and evaluated their efficacy in improving skin quality using meat duck models. Firstly, the optimal synthesis conditions of oZn (collagen peptide was mixed with Zn sulfate) were then identified using an L16 (4^4) orthogonal design, with a peptide-to-Zn ratio of 4:1, pH 5, 60°C, and 10-minute. Then, either inorganic Zn (iZn) or oZn supplementation (60 mg/kg) increased growth performance, skin Zn content, quality (piercing force and shear force), dermal thickness, collagen content, and upregulated skin proliferation-related genes (ELN, MAP3K7, and P63) mRNA expression compared with without Zn addition (Con) using meat duck models (P < 0.05). Proteomic profiling revealed 134 (Con-iZn) and 174 (Con-oZn) differentially expressed proteins (DEP) in skin involved in chromatin remodeling (P = 0.01) and ribosomal biogenesis (P = 0.02). Notably, oZn displayed superior efficacy in dermal properties through elevated collagen biosynthesis than iZn. In conclusion, optimized collagen peptide-zinc chelate (pH 5, 60°C, 10 min, 4:1 ratio) improved growth performance and skin quality in meat ducks. Organic zinc demonstrating greater efficacy through enhanced collagen biosynthesis and dermal thickness. These findings establish a theoretical basis for developing novel Zn sources as nutritional strategies to optimize skin health in meat duck.