Pathogenesis of Oviduct Lesions in Immature Chickens Following Exposure to Infectious Bronchitis Virus at One Day Old

SUMMARY The pathogenesis of oviduct lesions was studied in 220 pullets after exposure to infectious bronchitis virus (IBV) at one day old. Virus titers 65 hours after inoculation were greatest in the respiratory tissue, with titers in the reproductive tissue being comparable to those in other organs, such as kidney and bursa. Early changes consisted of mild lymphoid cell infiltrations in the oviduct wall and dilations of the rough-surfaced endoplastic reticulum of the epithelial cells. Later microscopic lesions in the oviduct consisted of areas of hypoplasia and nonpatency. Oviduct cysts were first observed on the 44th day postexposure. Localized hypoplasia of the oviduct, accompanied by occlusion of the oviduct lumen and the development of cysts, occurred in 22% of the birds.