Biological And Molecular Characterization Of Newcastle Disease Viruses Isolated From Apparently Healthy Goose Flocks

Newcastle disease (ND), which is caused by the Newcastle disease virus (NDV), is one of the most menacing highly contagious viral diseases of poultry and causes large economic losses in poultry production worldwide. Waterfowls were considered to be the natural reservoir for certain viral pathogens including avian influenza virus (AIV) and Newcastle disease virus (NDV). Aquatic birds, such as goose and duck, were usually considered to be resistant even to most virulent NDV strains. However, the goose flocks in some regions of South and East China have experienced severe outbreaks of NDV infection since 1997. Although measures have been taken to control the disease, it still spreaded progressively and became a substantial threat to goose farming. Researchers isolated lots of ND virues derived from outbreaks since late 1990s and have found many biology characters of those viruses.However, there are rarely researches about the NDV in apparently healthy geese till now. In the present investigation, we performed isolation and characterization of NDV from apparently healthy domestic geese in Jiangsu, Anhui and Shangdong proviences. By studying the biological and molecular characteristics of these NDV isolates, the status about NDV infection in apparently healthy domestic geese and the origin of those goose-pathogenic ND virues were discussed.