Abdominal Hernias occur in Middle Aged Hens when laying an egg or passing droppings. The tear in the muscle tissue allows part of the internal organs to slip through the gap. It is believed that the Abdominal Hernia can be congenital or acquired. Denoted by a swelling of the abdomen, and physical examination is not diagnostic by itself.

The cause is due to a weakening of the abdominal muscles. There appears to be some link to soft-shelled eggs trapped in the oviduct and also to the build up of fatty lipomas in the abdomen.
In large breeding rooms where detailed statistics are being kept, it can be identified on occasions that certain blood lines of females are susceptible to Abdominal Hernias therefore a congenital aspect of this illness does exist.

The first obvious indicator of a hernia is a swelling around the vent area, either after droppings are passed or an egg is laid. This swelling is likely to increase in size as the tear becomes larger. Droppings of the affected birds are often bigger and passed less frequently than normal, due to the weakness of the muscles of the abdomen.
Hernias can become very large to the extent that they can be confused with tumours.
Birds with a hernia appear to be in relatively good health, although the protrusion may become damaged by hitting perches etc and may bleed.
In some cases “organ strangulation” may occur when blood supply to an organ is restricted by the tear; if untreated this is fatal.

Unfortunately definitive diagnosis requires a veterinarian and the treatment requires a Veterinary surgeon. In Canaries it is regarded as major surgery.

It appears from the experience of breeders that hernias are infrequently found in Hens which are kept well fed and are NOT allowed to become too fat or obese. Hens should be fed a good diet of seeds greens and have an ample supply of shell grit or other calcium based food.

Published 25 May 2008