Chris Lesley helps us understand what to do with an egg-bound chicken.

When raising a backyard flock, nothing is more exciting than collecting a carton’s worth of eggs each day. Every chicken owner puts in a lot of work for their flock, from feeding the birds to cleaning the coop, and a fresh omelet is a nice reward for all that labor! But what happens when a hen isn’t laying her share of eggs every day? Well, there’s a chance that she may be egg bound, which is a serious health concern. But, what is egg binding exactly, and how can this problem be solved? Read on to find out!

What is Egg Binding?

When a hen is egg bound, she has an egg stuck inside of her and doesn’t pass from the shell gland to the vent. In a normal hen the laying process takes 25 hours, 24 of which are spent in the uterus while the shell is developed. Once the shell is formed the egg needs to exit through the vent. But, here’s the catch: the egg needs to turn around inside the hen’s reproductive tract before it can exit. The egg spends most of its time in the reproductive tract travelling, “pointy end first,” but the blunt end of the egg needs to exit the vent first. The egg must turn completely around; if the egg can’t turn around then it can’t exit, so it gets stuck in the reproductive tract and won’t budge.

Chicken anatomy. The ovaduct is where hens can get egg-bound. Adobestock/blurringmedia

Studies have found that egg binding is relatively rare. However, when it does occur, it is typically at the very beginning or the very end of the laying season.

What Causes Egg Binding?

There can be any number of reasons why a hen has become egg bound. Some of the most common causes are:

• Lack of calcium or protein. Calcium and protein are both critical to egg production, both for giving the hen energy and for actually forming the contents of the egg. Egg laying places a high metabolic demand on the hen, so their calcium and protein sources are depleted quickly. This is most common in hens whose bodies are not accustomed to laying yet, or for hens who have been laying massive quantities of eggs for an entire season.
• Obesity. Obese hens have weaker muscles and may not have the ability to pass an egg.
• Oddly-Shaped Eggs. As mentioned above, eggs must completely rotate before leaving the hen’s body. It’s already a tricky task, and oddly-shaped or oversized eggs will make it even harder. This is more common in newer laying hens, who are more prone to lay misshapen eggs.
• Infections or Parasites. Infections and parasites will often result in loss of muscle tone or nutrient depletion, which makes it hard to both produce and pass the egg.
• Genetic Predisposition. There are hereditary factors that predispose chickens to egg binding. Smaller size, as in Bantams, is one genetic factor that puts the hen at a higher risk for egg binding. Another hereditary factor is lipomatosis, or fatty tumor formation.

There may be other causes of egg binding as well, such as stress, premature laying, or simply refusing to lay the egg because a nest box is unavailable. It’s most likely that multiple factors will be at play when a hen becomes egg bound.

What Does Egg Binding Look Like?

Just as there’s a number of different causes of egg binding, there are also a variety of symptoms that can be present. Here are a few of the most common:

• “Penguin-walking.” This is when the hen seems to waddle, and her wings and tail are hanging down.
• Abdominal Strain or Swelling. The hen may appear swollen at the base of the tail and appears to be making the hen uncomfortable.
• The hen may seem weak, spend excessive time in the nest box, and will have her eyes half open.
• Atypical Feces. Normal hens may have diarrhea due to cloacal relaxation. Smaller hens may have constipation instead because the egg is interfering with defecation.
• Tail Pumping. This may include moving the tail up and down, or just strained movements of the tail. This is a tell-tale sign that she is trying to lay an egg, but just can’t.

Many symptoms of egg binding resemble other ailments. Since egg binding is relatively uncommon, there’s a good chance that the chicken with these symptoms has a different ailment. However, if she is egg bound, her life may be in danger! Due to this life threatening nature of egg binding, always be sure to complete a thorough examination before ruling it out as the cause of your hen’s discomfort. Normal to large birds may experience these symptoms for several days and will be alright. However, smaller birds will have a rapid onset, and unfortunately a rapid death too.

How is Egg Binding Treated?

The first step in treating an egg bound hen is to make sure that’s actually what’s wrong. You can do this by carefully palpating the abdomen; if you feel an egg, then she’s definitely egg bound. Be careful not to crack the egg, as this could cause a fatal E. coli infection. Also, note that an egg with a soft shell won’t be very easy to feel, but the abdomen will still be very swollen and soft.

The next step is bath time! Place the hen in a tub of water with ½ cup of Epsom salts per ½ gallon of water. Let her soak for 20 minutes, then place her in a dark area away from the flock to lay. This step can be repeated several times.

If necessary, you can lubricate the vent with K-Y or petroleum jelly, or even give calcium or oxytocin injections to induce contractions of the abdomen.

Another option is egg piecemeal, in which the egg contents are taken out by poking a hole in the shell and taking them out with a syringe. Then, the shell is removed separately. This should be done by a veterinarian, as it is extremely risky. Sometimes, a hen may have multiple eggs built up behind one stubborn egg. This will require a vet as well, and can be very costly.

Egg binding is not a fun process for any hen or her owner. While it can be treated, it is best to prevent it altogether. To prevent egg binding and keep your layers healthy, give them the correct feed, control the spread of infections or parasites, and keep the stress levels low!

Chris Lesley has been raising chickens for over 20 years and is a fourth generation chicken keeper.