Egg Yolk Peritonitis

A hen will sometimes become a ‘blind’ or ‘internal’ layer which can lead to Egg Yolk Peritonitis (EYP).

The yolk is produced but misses the infundibulum and becomes a free-floating yolk in the abdominal cavity. This yolk has no way of leaving the abdomen and a hen will develop a typical penguin-like stance becoming very upright with a large swollen hard belly. The hen will often have a vibrant red comb (Figure 1) denoting she is in lay.


  • Lethargy.
  • Enlarged hard abdomen sometimes with a prominent keel.
  • Ceased egg production.
  • Reduced activity.
  • Reduced appetite.
  • Penguin-like stance.
  • Waddling gait.


  • Diseases of the ovary causing eggs to fail to enter the oviduct. Some examples are:
    • Cystic ovaries
    • Neoplasia (cancer)
    • Salpingitis
  • If egg enters the abdominal cavity occasionally it is generally self-resolving as the yolk material is sterile and will only cause a mild inflammatory response. However, if it is a recurring problem the yolk will build up and, as it is an excellent growth medium for bacteria, it can cause a secondary bacterial infection.


Note that this home remedy is not intended to offer a cure or replace veterinary treatment, but may alleviate symptoms where no professional support is easily available. The suggestions are based on experience gained with our own hens.
  • A low calcium diet of corn can help bring a hen off lay helping to halt further egg production.
  • As the belly becomes larger the hen will struggle to feed and breathe properly, and may become uncomfortable. Place food and water bowls on a brick or similar to aid easier access.
  • Please consult your vet for advice; there are treatment options available.
  • Your vet may recommend a hormone implant which will take your hen off lay and could provide relief from symptoms for roughly 6 to 9 months.


There is no way to prevent this condition.

Egg Yolk Peritonitis
Figure 1: A hen will often have a vibrant red comb denoting she is in lay

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