The best-known avian coronavirus and the most important economically and from a welfare point of view, is avian Infectious bronchitis virus. The primary target organ is the respiratory tract, where initial infection and disease occurs but IBV also affects renal tubular epithelial cells and the oviduct.

When the left oviduct is affected, the single developed, in birds occurs salpingitis with the resulting alteration of shell morphology. The right oviduct, undeveloped, can be affected too with accumulation of clear liquid or purulent. As you can see in the two photos of layer hens, in the right we can see the left developed oviduct and formed eggs ready for laying. In the left we can see a normal right oviduct, less developed, and in the other photo a right larger oviduct and full of liquid. This lesion showed that well vaccinated birds have resisted the battle against the field virus of avian Infectious bronchitis although its right oviduct has been filled with liquid. Similar situations are frequent in farms situated in passage areas for migratory birds that are sometimes IBV carriers.