Aviadenoviruses (avian adenovirus) affects chickens, ducks, turkeys, geese and pheasants. They are icosahedral, non-enveloped, and have a double strand DNA genome. Avian adenovirus can cause specific disease and other complications in affected fowl:
- Egg Drop Syndrome (EDS)
- Pheasant Marble Spleen Disease (MSD)
- Quail Bronchitis (QB)
- Haemorrhagic Enteritis (HE)
- Inclusion Body Hepatitis (IBH)
The most common types of the avian adeno-associated virus worldwide are serogroups 1, 2, and 3, with all three often found in one locality and even sometimes on the same farm.
Avian adenovirus may also affect other organs in the birds’ body. Other conditions that may develop are hepatitis, bronchitis, pancreatitis, oedema, ventriculitis, and splenitis. These other conditions will develop according to the type of bird affected by the adenovirus.
Avian Adenovirus Transmission
The virus is usually spread oro-fecally. The virus tends to replicate in the gut, and therefore the virus is excreted via the body through the birds’ faeces. It may remain latent until the bird is stressed, at which time clinical symptoms appear. There is no evidence of transmission to humans.
Avian Adenovirus Symptoms and Diagnosis
Clinical signs of illness appear according to the organ affected. As mentioned above, the bird may exhibit one or more of EDS, MSD, QB, HE, or IBH. Additionally, the bird’s stool may exhibit an unusal odour or be liquid. Anorexia is also seen as is diarrhea.
Diagnosis is by histopathology, electron microscope, and ELISA. Postmortem exam reveals clinical signs in the affected organ.
Avian Adenovirus Vaccines and Treatment
Vaccines are available for Haemorrhagic Enteritis and Egg Drop Syndrome. Reducing stress levels and affording adequate nutrition and proper hygiene can ward off infection. Taking care to not mix faeces of different flocks can also prevent the transmission of avian adeno-associated virus as faeces can contain virus particles.
Always consult your veterinary professional when you suspect a sick bird.