Chronic egg-laying occurs when a female bird lays one egg after another or lays repeated clutches of eggs. Chronic egg-laying may lead to malnutrition from the chronic depletion of calcium from the body for the production of eggshells. In time, calcium depletion may result in egg binding. A lack of hormonal feedback to a bird’s brain, telling the bird to stop laying eggs, likely occurs in chronic egg-laying birds. Removing eggs that are already laid may induce birds to lay even more eggs, depending on the species. Egg-laying uses up a great deal of the bird’s body stores of calcium not only to make eggshells, but also to help contract muscles and stimulate nerve conduction to push eggs down the bird’ reproductive tract. Birds eating all-seed, calcium-deficient diets may not be able to replace depleted calcium stores quickly enough, and they suffer from hypocalcemia. There are both behavioral and medical interventions to stop chronic egg-laying.
Egg binding is not uncommon in birds and may be resolved easily if treated early. Egg binding occurs when the female bird is unable to expel the egg from her body. If a prolonged period has elapsed since the bird began attempting to lay the egg, she may become critically ill. Birds with egg binding may or may not have passed an egg more than 2 days ago, are usually weak, not perching, often sitting low on the perch or on the bottom of the cage, and are straining as if trying to defecate or to lay an egg. Treatment varies depending upon how sick the bird is, as well as the location of the egg and the length of time the bird has been egg bound. Critically ill birds are first treated supportively for shock, and then attempts are made to extract the egg. If your veterinarian cannot see the egg through the vent, surgery under general anesthetic may be necessary to remove the egg from the abdomen. A hysterectomy (removal of the oviduct and uterus) is typically the last choice therapy, when medical and egg extraction through the vent are not possible.