Virus related plumage disorders

Virus related plumage disorders

Some viruses, such as polyomamavirus (French moult) or circovirus (PBFD), cause diseases that can result in massive virus-related plumage disorders.


  • The viruses can be transmitted by inhaling feather dust or ingesting contaminated droppings or crop secretions via feed or water-.
  • Likewise, it can be transferred from the hen to the fertilized egg.


  • Damage to the follicles initially causes the wing feathers to fail or break off, and later the down feathers.
  • The stumps of the feathers are often encrusted with blood,
  • Regrown feathers are deformed and feather shafts may be brownish in color due to bleeding in them.
  • Amplification of the clinical picture from moult to moult
  • Massive weakening of the immune system, making the budgie susceptible to other pathogens.


The viruses can be detected in the blood of the bird or in deformed but still living feathers. However, the tests may have to be repeated, as the weakened immune system can lead to false negative results.


Since there is unfortunately no therapy that can fight the virus itself, it is only possible to delay the progression of the disease.

  • Immune stimulants and multivitamin preparations with high vitamin A content
  • Symptomatic treatment
  • Control of additional infections

Uninfected birds

It is essential to separate patients from healthy birds, as they can transmit the virus directly (feather dust, secretions, feces) or indirectly (objects).

  • Doris Quinten: “Ziervogelkrankheiten”, p. 53f.