Histological examination
Portions fresh tissues (e.g., liver and kidney) from infected ducks were
fixed with a10% neutral buffered formalin, sectioned into 4–5μm thick
with paraffin and stained with haematoxylin and eosin using standard
methods. Tissues samples (e.g., liver and kidney) from the diseased or
experimental ducklings were frozen for virus isolation and
identification.