Different calcium levels and inclusion of phytase in laying hen diets affect egg quality stored for 14 days.

Calcium is an essential mineral for improving egg quality and its availability can be enhanced by the phytase enzyme. A trial was conducted to determine the effect of calcium levels and phytase inclusion at 2500 FTU/kg diet on egg quality kept for 14 days. This trial used 216 hens, aged 22 weeks old. The hens were reared for 12 weeks and fed with different calcium concentrations (2, 3, and 4%) with or without phytase supplementation. The diets and water were offered ad-libitum. A completely randomized factorial design was used. Analysis of variance and Tukey test were applied. The significant effect of calcium levels was found in the parameters of eggshell percentage and eggshell thickness (P<0.05). Phytase could improve the qualities of eggshell, yolk, and albumen. Egg shape index, albumen percentage, yolk percentage, and yolk colour were not affected by phytase. There was no interaction between calcium levels and phytase inclusion on all parameters of egg quality. In conclusion, the increased inclusion of calcium from 2% to 3 and 4 % increased eggshell percentage and eggshell thickness. Phytase inclusion increased the qualities of eggshell, yolk, and albumen. Calcium level and phytase did not have interaction in affecting all egg quality parameters. [ABSTRACT FROM AUTHOR]