Duck plague in gnotobiotic ducks.

Four-week-old gnotobiotic and conventional ducks were inoculated orally with duck plague virus. Both groups of ducks died on the third and fourth day after inoculation. Gross and microscopic lesions of duck plague were similar in gnotobiotic and conventional ducks, indicating the synergistic action of species of Salmonella and Pasteurella was not essential for development of lesions.