Information from Merck Vet Manual
|Here are several other articles about weird eggs. If your bird has laid one, it might be an isolated case or a sign of big trouble. For your bird's sake take the time to read these and understand.|
Weird Eggs - Peter Brown
(See the Merck manual definition of Internal and False Layers below)
These conditions are often chronic and get only worse with time. They eventually lead to secondary peritonitis or ascites killing the bird.
Merck Vet Manual
In these hens, partially or fully formed eggs are found in the abdominal cavity. Such eggs reach the cavity by reverse peristalsis of the oviduct. If they have no shell, they are often misshapen due to partial or complete absorption of the contents. Frequently, only empty shell membranes are present. No control or treatment is known. This condition is related to erratic ovulation and defective eggs (see Defective or Abnormal Eggs).
These hens ovulate normally, but the yolk is dropped into the abdominal cavity rather than being collected by the oviduct because of obstruction of the oviduct after infection with E coli or Mycoplasma gallisepticum. The yolk is absorbed from the abdominal cavity. The hen looks like a normal layer but does not produce eggs. Hypoplasia of the ovary and oviduct has been associated with infectious bronchitis virus infections (see Infectious Bronchitis: Introduction) at an early age (1-2 wk). Atresia or even atrophy of the ovary are caused by severe stress, chronic infections, and feed refusal due to mycotoxins in the feed.
Hypoplasia: Underdevelopment or incomplete development of a tissue or organ.
Atresia: Absence of a normal opening or failure of a structure to be tubular.