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.