I found this on another forum and thought it most helpful.
There are many things that can happen that may cause an emergency situation to arise during the breeding/egg laying process such as egg binding, egg peritonitis and prolapsed uterus and death.
Egg binding is when the bird cannot pass an egg and it has become “stuck” inside the hen causing obstruction of the uterus or oviduct leading to a prolapsed uterus. It takes 24-25 hours for the egg to form. If the egg remains in the oviduct for longer periods it can cause the oviduct to rupture.
Egg binding can be caused by obesity, no exorcize, heredity, an inadequate diet which lacks calcium and essential vitamins & minerals, mal-formed eggs, over laying and damage to or infection of the oviduct. This condition requires immediate VET assistance and can cost you the life of your hen.
Egg peritonitis is when the birds suffers an inflammation of the abdomen (peritoneal cavity) caused by leaking from the oviduct & ovaries the contents of the mal formed or broken egg inside of her which can allow the yolk to enter the bloodstream causing bacterial infection, poisoning and death. This condition also requires immediate VET assistance.
There are many other things such as a ruptured oviduct, prolapsed uterus or a hen can push/strain so hard that they push out her insides through the vent; this is very serious and can cause death in most cases.
If you believe your hen IS egg bound….
In my opinion THIS IS AN EMERGENCY SITUATION! You need to get your hen to a Farm animal Vet NOW!! As I am unable to see your hen, and by your brief description of the hen symptoms suggests it is in need of IMMEDIATE avian vet attention! I cannot diagnose this problem and if the hen does have a tumor, an infection or is in fact egg bound it is most likely suffering.
If egg bound; this pain/suffering/stress will not go away until the egg has passed or been removed by the vet or the hen dies. In this situation you definitely need a visit to the vet NOW rather than later as every minute that is passing by your hen is in pain & suffering.
DO NOT try to remove a bound/stuck egg yourself… ever! The egg could break inside the hen leading to pain, suffering, infection and/or death. If internal organs have been pushed out of the vent by the hens straining, DO NOT try to push them back in your self. These are life-threatening situations that require delicate procedures performed certified farm animal specialists. Some times these hens will still circum to their ailment/injuries depending on the severity.
Below are posted some links to pictures and avian x-rays showing abnormal (egg bound) illustrations for your review. This will give you an idea of where the swelling or hardness may occur if your hen is egg bound. These pictures may not be that of a chicken but the illustrations/x-rays will show you what egg binding looks like and give you an idea of how painful this condition is for your hen.
Avian x-rays: Egg Bound
Also have a look at this.
Calcivet (CalciBoost) (liquid) Customer Comments
Liquid calcium supplement for breeding and growing birds. Has been found to be very effective as an emergency product for egg-bound hens.
Application: In water (10-20 mls per litre) or on soft-food 0.1-0.2 mls per 100g bodyweight. Use the lower doses in hard water areas.
Pack sizes: 100ml, 250ml, 500ml, 1 litre, 5 litres.
Active ingredients: Magnesium, Vitamin D3, Calcium.
Shelf-life: Normally 16-18 months.
http://www.birdcareco.com/English/Produ ... rlist.html