Experimental infection of special-pathogen-free chickens with serotype-1 fowl adenovirus isolated from a broiler chicken with gizzard erosions

Gizzard lesions were formed in specific-pathogen-free (SPF) white leghorn chickens inoculated with fowl adenovirus (FAV). The virus, serotype 1 FAV 99ZH strain (FAV-99ZH), was originally isolated from the gizzard mucosa of commercial broiler chickens exhibiting gizzard erosion with intranuclear inclusion bodies. Five-day-old and 53-day-old SPF white leghorn chickens were inoculated with FAV-99ZH by both oral and ocular routes and then examined at necropsy on days 3, 5, 7, 10, 14, and 21 postinoculation (PI). There were no clinical signs in any of the chickens after the inoculation. Focal gizzard lesions occurred macroscopically, however, in inoculated chickens at several experimental periods. FAV was recovered from tissue samples of the proventriculus, gizzard, pancreas, and rectum by day 10 or 7 PI but was not recovered from liver samples of any of the chickens. These results indicate chat FAV isolated from gizzard erosion is able to reproduce gizzard lesions as necrosis and erosion in SPF white leghorn chickens and that it may have a greater degree of tissue tropism in gizzards and other digestive organs than in the liver.