A novel source of calcium: effects of calcium pidolate concentration on egg quality in aged laying quails (Coturnix coturnix Japonica)

Calcium content in the diet can affect egg quality and production in aged birds. Calcium pidolate is a new form of calcium supplementation in poultry diets, which favours the absorption of this mineral. The current study was conducted to evaluate the effect of dietary calcium pidolate concentration in the diets of aged laying Japanese quails. A total of 120 female quails (27 weeks old) were assigned to four treatment groups, each with six replicates of five quails per pen. In the 10-week trial, quail diets were supplemented with calcium pidolate at four concentrations (0, 0.25, 0.50 and 1.00 g/kg), providing 25.1, 25.4, 25.8 and 26.5 g/kg calcium, respectively. As a result of this study, body weight, feed intake and feed conversion ratio did not change with the concentration of calcium pidolate (P > 0.05). In contrast, albumen and yolk index decreased as calcium pidolate level increased (P < 0.05). Moreover, calcium pidolate at a concentration of 0.50 g/kg resulted in the greatest egg production, eggshell breaking strength and eggshell thickness (P < 0.05), while above these levels the factors studied were negatively affected. According to these results, the optimal concentration of calcium pidolate in the diets of aged laying quails was 0.50 g/kg.