How do chickens lay eggs?

Posted by AcreageLife on Sep 22, 2022 10:30:00 AM

The process behind egg-laying magic  

Most flock raisers know there’s something special about walking to the backyard and grabbing a few eggs for breakfast. But how do chickens lay eggs? 


At their peak, laying hens can lay up to one egg per day. The magic behind each egg is a 24-to-26-hour process, with much of the work happening overnight. 


Yolk releases (1/2 hour):

Most chickens begin developing yolks at 18 weeks old. Once a yolk starts to develop, it spends 10 days growing. Then it releases into the infundibulum or oviduct. 


Initial egg white is created (3 hours):

As the egg enters the hen’s reproductive tract, the egg white forms. In the magnum, layers of thick and thin proteins, known as the albumen, create the egg white. As the contents travel down the oviduct, they spin. This spinning causes formation of the chalazae (the white, stringy pieces in an egg). The chalazae’s role is to keep the yolk in the center of the egg.


Egg shape is formed (1 hour):

Before the egg enters the shell gland, it spends an hour in the isthmus. While there, the inner and outer shell membranes are added around the albumen and it takes on the oval shape.


Eggshells are formed (20 hours):

The most significant piece of the egg formation process happens in the uterus or “shell gland.” The developing egg spends about 20 hours in the shell gland, where the shell is formed and eggshell color is added during the last 5 hours.

The shell takes the longest to form. This is why it’s important hens are fed a diet containing the proper nutrients to produce strong shells. A layer feed with the Oyster Strong® System will provide your hens all the nutrients they need for strong shells.  


Egg bloom is added and egg emerges (seconds): 

The formed egg travels to the vaginal area where egg bloom is added to the shell to protect the egg from bacteria. A natural lubricant is also added for a safe exit through the cloaca.


For more layer chicken nutrition and helpful resources, visit . 

Tags: Poultry Lifestyle


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