Optimization of Zinc Hydroxychloride Levels in Quail Diets: Impacts on Performance, Yolk Antioxidant Capacity, Bone Development, and Mineral Excretion

Zinc (Zn) is crucial for animal physiology, yet traditional forms have limitations, prompting the exploration of alternatives such as zinc hydroxychloride (ZnOHCl). This study aims to determine the impact of dietary ZnOHCl on the productive performance, eggshell quality, antioxidant status of yolk, tibia mineralization, and mineral excretion in laying quails. One hundred and twenty-five 10-week-old layer quails were randomly assigned to five experimental groups. The experimental groups received a basal diet containing 34.14 mg/kg Zn from raw materials without additional ZnOHCl supplementation. The other four groups received the same basal diet containing 50, 75, 100, or 125 mg/kg Zn supplemented with ZnOHCl. The feeding trial lasted for 12 weeks. Feed intake was significantly (P < 0.05) lower in non-supplemented quails, while the rest of the performance parameters (including final body weight, body weight gain, and feed conversion ratio) remained unaffected (P > 0.05), which is similar to those described for egg production parameters (such as hen day egg production, egg weight and egg mass). Dietary ZnOHCl did not significantly (P > 0.05) enhance eggshell quality but showed potential to improve antioxidant capacity as evidenced by elevated 2,2-diphenyl-1-picrylhydrazyl values (P < 0.01). Zinc excretion in excreta increased with the highest level of ZnOHCl, while another mineral excretion was not affected significantly (P > 0.05). Surprisingly, ZnOHCl supplementation did not substantially impact tibia mineral content, indicating that the role of Zn in bone mineralization may involve more complex interactions than previously understood. Present findings indicate that supplementation with ZnOHCl at 100 mg/kg in quail diets may enhance the antioxidant capacity of the yolk without adversely affecting other productive parameters or exacerbating environmental impacts.