Effect of Age on Physio-Chemical Properties of Eggshell of Domestic Fowl

Abstract

Investigations were conducted on the effect of age of laying birds on the physical and chemical properties of eggshell when the birds were 22, 34, 46 and 58 weeks old. The birds were housed in battery cages and given water and layer's diet (17% C.P. and 3.20% Ca) ad lib.
The result of the study showed mean eggshell weight of 5.43, 5.33, 5.30 and 4.92g at 22, 34, 46 and 58 weeks respectively. The shell membrane weights at 22 and 34 weeks were significantly lower than those of 46 and 58 weeks. There were also significant differences (P < 0.05) between shell thickness, shell porosity and specific gravity at the different ages of laying.
The magnesium and phosphorus content of the shells showed a significant increase with the advancing age of the birds. The calcium content of the shell at 46 weeks was significantly lower (P < 0.05) than those of 22 and 58 weeks. Significant differences (P < 0.05) were observed both in the physical and chemical properties of the eggshell at the different ages of the birds.