Indirect response in egg production and egg quality traits due to selection for body weight at 8 weeks of age in dandarawi chicken

الملخص EN

The poultry industry mainly aims to produce genetically superior birds with high productivity of meat and egg.

The current experiment was carried out on Dandarawi chickens selected for high body weight at 8 weeks of age through two successive generations to detect the indirect response in egg production and egg quality traits.

Traits under study were age at sexual maturity, egg weight, laying rate, total egg mass and egg quality.

Results indicated that age at sexual maturity, average of laying rate, and egg weight were highly (P≤0.01) affected by generations.

Also, the effect of generation was significant (P<0.05) on total egg mass.

The pullets in selected line matured (165.44 day) later than those in control line (161.47 day).

Moreover, the birds in selected line had laying heavier egg weight than those in the control line.

The results showed no interactions between generations and lines considering all egg production traits.

Regarding egg quality traits, egg weights were greatly affected by lines (P≤0.01).

Furthermore, albumen percentage and eggshell thickness were significantly (P<0.05) affected by lines.

In conclusion, selection for body weight at 8 weeks of age tended to delay the age at sexual maturity, decreased laying rate, increased egg weight, and decreased total egg mass in the selected line as an indirect response to selection.

Egg quality was slightly affected indirectly by selection for high body weight at 8 weeks of age.