Egg binding occurs when the egg does not pass through the reproductive system at a normal rate. Egg bound occurs when there is difficulty in laying an egg because of an inflammation of the oviduct or partial paralysis of the muscles of the oviduct and production of a very large egg that can not be laid physically. This is common, and often preventable, problems in broiler breeders and not exposed to a mate, since eggs may be formed and laid without the presence of a male. This condition goes on for too long, complications and death, especially in underweight birds.
Photo 1: Showing egg bound in oviduct
Photo 2: Egg yolk leads to salpingitis
Factors causing risk of egg binding:
There are a number of factors that can increase the risk of egg binding.
1. Species: Egg binding is more Commercial Layers, Broiler Breeder Layers.
2. Age: Young birds laying for the first time, as well as "old" birds more commonly become egg bound.
3. Reproductive health: Hens with reproductive problems or those that have a laying malformed or soft-shelled egg are more prone to egg binding.
4. Malnutrition: Birds having diets those with deficiencies in calcium, vitamin A, protein, vitamin E, or selenium are at higher risk.
5. Overall health: Egg binding is more common in birds with over weight problems such as obesity as well as those under stress from environmental conditions such as improper temperature.
6. Egg abnormalities: An overly large or malformed egg, or one that is not positioned correctly, is broken, or joined to other eggs.
7. Genetics: Certain lines of birds may be genetically predisposed to egg binding.
Suspected causes for egg binding:
• Low Calcium Levels or Hypocalcaemia Syndrome associated with low calcium levels in the blood. Supplementing the breeding hen with a diet rich in calcium and Vitamin D is an important factor in preventing this problem.
• Malnutrition caused by unbalance or low-protein diets.
• Sedentary lifestyle: Often the case when birds are kept in cages that is too small for them. The lack of exercise causes poorly developed muscles and obesity.
• At particular risk are sick and old birds.
• Chronic egg laying.
Signs will vary depending upon the severity of condition and can include:
• Abdominal straining
• Bobbing or wagging of the tail
• Drooping of the wings
• Wide stance
• Loss of appetite
• Lameness or leg paralysis (the egg puts pressure on the nerves going to the legs)
• Distended abdomen
• Droppings stuck to the vent area (the bird cannot raise her tail when passing waste)
• Some hens may pass large wet droppings while others may not pass any droppings due to the egg's interfering with normal defecation.
• Fluffed feathers
• Difficult breathing (the retained egg puts pressure on the air sacs)
• Sitting fluffed on the bottom of the cage
• Possible prolapse of part of the reproductive tract (the inner part of the reproductive tract is pushed out so that it is visible as a pink mass protruding from cloacal opening)
• Complications from being egg bound can be swelling, bleeding or prolapse of the oviduct.
• Sudden death
The veterinarian will make the diagnosis based on the clinical signs, history and physical examination If the bird is much stressed or in shock, it will be necessary to stabilize her before proceeding with extensive examinations.
The treatment will depend on the condition of the bird, severity of the signs, where the egg is located, and the length of time the bird has been egg bound. In egg bound syndrome, birds not give the proper response to treatment.
• Elevation of the humidity to 60% and increasing the environmental temperature to 85-90°F
• Liquid calcium, and possibly vitamins A, D3, and E, and selenium through drinking water.
• Administration of electrolyte through drinking water.
• Continued access to food and water
• Provide bird with high-calorie, high-calcium diet to help strengthen future eggs and prevent egg binding.
If left untreated, egg binding can result in shock and death, often within hours. In addition, other complications are more likely to occur including:
• The retained egg may place pressure on the kidneys, affecting their function and health.
• If the egg ruptures while still inside of the bird, life-threatening peritonitis (a serious inflammation of the abdominal cavity) can occur.
• Constant straining may cause prolapse of the reproductive tract or cloaca. This can result in egg peritonitis, infection, or scarring that could result in further problems with egg binding.
The risk of egg binding may be decreased by:
• Providing the nutritional balance diet.
• Using proper breeding techniques including timing of Artificial Insemination start A.I. at an appropriate age and Std. Body weight.
• Removing genetically predisposed birds from the breeding flocks.
• Providing the correct environmental conditions (i.e. temperature 85-900F and humidity 60%).
• Prevent excessive light or light intensity in peak production so that to try to avoid double yolk eggs (jumbo eggs).
• Preventing obesity.