The Eggshell Structures Of Ringed Turtle - Doves (Streptopelia risoria)

Abstract

The avian egg provides nutrients and protects the growing embryo from physical and microbial harm. Structures fundamental to the protection are the membrane layers, which are tightly meshed networks of collagen fibers, and the eggshell, which is composed of calcite crystals, (CaC03). The eggs of Ringed Turtle-Dove and commercially bred chickens were selected for the study. Eggs of commercially bred chickens are twice in length and width of the dove eggs. Features analyzed are components of quality and strength of eggshells included shell thickness, membrane thickness, and concentration and size of vesicles. A comparative study of the bird eggs was designed to examine these structures. Scanning electron microscopy was used to examine and compare the eggs from two species of birds. The hypothesis was that the relationship of the ultrastructures seen in chicken eggs would be twice the measurement of those found in the dove eggs.