Yolk formation: This is the initial stage, where the hen's body starts to accumulate nutrients and yolk material in the ovary.
White formation: Once the yolk is ready, the hen's oviduct starts to add layers of albumen or egg white around the yolk.
Shell formation: This is the final stage, where the remaining part of the oviduct adds layers of calcium and other minerals to create the eggshell.
After being laid, the egg may undergo further internal changes as it moves through the hen's reproductive tract until it is eventually expelled through the cloaca, completing the egg-laying process.