The effects of dietary calcium tetraborate on the ovalbumin levels and some egg quality traits in laying quails exposed to cadmium

Cadmium (Cd) is a toxic heavy metal and one of the most important environmental pollutant that is derived from agricultural and industrial sources. Boron (B) is a metalloid that has beneficial physiological effects on the metabolism of animals and humans. This research is aimed at investigating the effect of calcium tetraborate (CaB4O7) on the ovalbumin levels of quail’s egg and some egg quality traits in laying quails exposed to Cd. For this purpose, one hundred twenty Japanese quail 6-week-old were randomly divided into 4 groups (5 replicates each). During the 8 weeks, quails were fed a basal diet (control) and basal diet supplemented with Cd (100 mg of CdCl2), CaB4O7 (300 mg of CaB4O7), and Cd + CaB4O7 (100 mg of CdCl2 and 300 mg of CaB4O7). A total of 160 eggs including 40 eggs from each group were collected for assessment of the quality of the egg and the ovalbumin level of the eggs. Compared with the Cd group, supplementation of Cd + CaB4O7 increased the egg weight (P < 0.01). Results of this study indicated that dietary supplementation with Cd or CaB4O7 was not affected significantly albumen pH, yolk ratio, and yolk color (P > 0.05). Regarding the egg quality, the significant effect of Cd or CaB4O7 (P < 0.01) was found in shape index, yolk weight, albumen weight, and yolk pH. The dietary combination of Cd and CaB4O7 led to the greatest increases in albumen ratio (P < 0.01). The Cd group had the highest ovalbumin level, while CaB4O7 and Cd + CaB4O7 groups had the same ovalbumin level. The findings of this study revealed that provided new insight into the toxicity of the Cd on ovalbumin level and some egg quality traits and CaB4O7 could be used as a potential strategy to ameliorate Cd toxicity.