The present review focuses on three avian DNA viruses and two retroviruses; the DNA viruses are Marek's disease, chicken anaemia and fowlpox virus. The two avian retroviruses, reticuloendotheliosis and avian leucosis virus subgroup J were detected in theirproviral DNA form in the feathertip extracts, thus resembling DNA viruses. Whereas most previous reports focused on experimentally-infected chickens, in the present study we analysed naturally-infected commercial flocks.
We review now the presence of various viruses in the chicken feathers, showing the efficacy of feathers for research and diagnosis alongside with other organs. Data on the relative ability to detect viruses on feathers over prolonged periods of time is also provided. We also analysed the efficacy of feather testing for the assessment of environmental infection in poultry houses. The data obtained by the differential diagnosis of various viruses in conjunction with the analysis of organs from the same chickens, showed that the feathers were very effective for diagnosis and deserve more attention.
