Susceptibility of ducks and duck-origin cell cultures to infectious bursal disease virus

Specific-pathogen-free (SPF) ducks that were 1, 3, 4, 7, 10, 30, and 180 days old were inoculated experimentally orally or nasally with infectious bursal disease virus (IBDV). Attempts to induce clinical disease in ducks with strain J1 or FK-78 of IBDV were unsuccessful. Virus-recovery attempts from organ and intestinal contents were also unsuccessful. No significant gross or histopathological lesions were found in liver, spleen, kidney, heart, or bursa of Fabricius of 1- and 3-day-old ducks at 4 or 7 days postinoculation. The ratios of bursa weight to body weight of 1-, 10-, and 30-day-old inoculated and control ducks revealed no difference at 21 days postinoculation. The ducks responded serologically, however, by developing both virus-neutralizing and agar-gel-precipitin antibodies. Virus multiplied in embryonated duck eggs and duck embryo fibroblast cells but not in duck kidney cells.