Avian Nephritis Virus Research Articles

Visceral urate deposits in chicks inoculated with avian nephritis virus

Avian nephritis virus, G-4260 strain, was inoculated orally into one-day-old specific-pathogen-free chicks of two lines. Approximately 20 per cent of the chicks of both lines died with visceral urate deposits from eight to 12 days after infection, and the virus was isolated from the kidneys of the dead chicks. At 14 or 15 days of age the mean liveweight of the surviving infected chicks was approximately 16 per cent less than that of the uninfected control chicks.

A survey of specific pathogen‐free chicken flocks for antibodies to chicken anaemia agent, avian nephritis virus and group a rotavirus

Sera originating from specific pathogen-free flocks from Europe, North America and Australia were examined by indirect immuno-fluorescence for antibodies to chicken anaemia agent, avian nephritis virus and group A rotavirus. Some flocks were free of infection, but others showed evidence of infection with one, two or all of these viruses. In view of the pathogenic potential of these viruses and the possibility that they may be egg-transmitted, it is recommended that their elimination from specific pathogen-free flocks should be viewed as a priority.

A survey of avian sera from Northern Ireland for antibody to avian nephritis virus

Sera from chickens, turkeys and ducks were examined for antibody to avian nephritis virus, by indirect immunofluorescence. Antibody was found to be widespread in commercial fowls and turkeys and was also detected in sera from specific pathogen-free chickens. No antibody was detected in a limited number of duck sera tested. The possibility of contamination of avian vaccines with avian nephritis virus is discussed.

Susceptibility of Chickens to Avian Nephritis Virus at Various Inoculation Routes and Ages

Factors that influence the response of chickens to avian nephritis virus (ANV) were studied. Day-old specific-pathogen-free chicks were inoculated with the G-4260 strain of ANV by oral, subcutaneous, intratracheal, intramuscular, and intracerebral routes at a dose of 10(5.0) plaque-forming units (PFUs) per chick. Inoculation induced only nephritis, and contact infection ANV occurred very easily. When 1-, 14-, 28-, 56-, and 300-day-old chickens were inoculated orally with 10(5.0) PFUs of the virus, the day-old chicks appeared to be most susceptible; histopathological responses to the virus became weak as chicks aged. The serological response of 28-day-old chickens to ANV was stronger that those of other groups. Pathologically, the adult chickens hardly responded to the virus, but they produced antibodies against the virus.

Pathological Changes in Chicks Inoculated with the Picornavirus "Avian Nephritis Virus"

One-day-old chicks were inoculated intraperitoneally with a newly isolated picornavirus. The inoculated chicks showed no clinical signs until 28 days postinoculation (PI), but discoloration of the kidneys was recognized from 7 to 21 days PI at autopsy. Histologically, focal lesions were observed in the cortex of the kidneys from 3 to 21 days PI. The lesions were characterized by interstitial lymphocytic infiltration and degeneration of epithelial cells of the proximal convoluted tubules. The degenerated cells contained acidophilic granules in their cytoplasm. Electron-microscope examination of the cytoplasm revealed electron-dense amorphous areas, phagosomal areas with viral particles, and isolated crystal arrays of the virus particles, 23 to 30 nm in size. Granular antigen was also detected by fluorescent-antibody technique in the cells.

Pathogenicity for Baby Chicks of the G-4260 Strain of the Picornavirus "Avian Nephritis Virus"

The pathogenicity of the G-4260 strain of picornavirus for day-old chicks was studied by intraperitoneal inoculation. No clinical signs were observed. A mild yellowish-tan discoloration of the kidneys was noticed in necropsy 7 to 21 days after inoculation. Mean body weight was significantly lower (P less than 0.01) in inoculated groups than in control groups 7 days after inoculation. In a chronological study on the distribution of the virus in organs, the virus was recovered from various organs, exclusive of the brain and trachea. The virus titer was higher in the kidneys, jejunum, rectum, and bursa of Fabricius than in any other organ. Fluorescent antigens were seen predominantly in the epithelia of the renal tubules.