Goose parvovirus, also known as Derzsy's disease, is a highly contagious acute disease of young goslings and Muscovy ducks that causes fatal goose hepatitis. Mortality rates reach 70-100% in goslings less than 4 weeks old and mortality decreases with increasing age. In adult poultry the disease is asymptomatic (vironosichi). The pathogen is goose parvovirus (GPV).
Sick goslings do not accept feed or water and squeal, and there is apathy, coldness, conjunctivitis, reddening of the skin, loss of feathers on the back and neck, and diarrhoea. Liver and heart damage also occurs. Some goslings die with no clinical signs.