Characterization of Agents Isolated from Market Chickens in a Quest for Enteric Viruses

Thirty-four agents of 3 or more antigenic types were isolated in chick kidney tissue culture from single cloacal swabs of 60 young market chickens. Some properties of 2 of the isolates, strains 65 and 93, were studied. Both produced an adenovirus-like cytopathic effect and were ether-resistant. Neither agglutinated chick red cells or was antigenically related to several other well characterized avian viruses. Small series of normal sera from humans, monkeys, calves, guinea pigs, and rabbits contained no neutralizing antibody to either agent. Strain 65 was antigenically related to the viruses of GAL types 1 and 2 and strain 93 to GAL types 3 and 4 and EV-89. Strain 93 was inactivated by formaldehyde and by heating at 80 C, but not 70 C. It did not agglutinate sheep red cells but agglutinated rat red cells at 37 C. A marked increase in nuclear deoxyribonucleic acid content was present in chick kidney cells infected with strain 93 and stained at 20 hours with the Feulgen and acridine orange techniques. An accumulation of intranuclear ribonucleic acid was also observed. By immunofluorescent staining the viral antigen was visualized in particulate form within the nucleus. No evidence of virus was observed in the nucleolus or cytoplasm. On the basis of the properties of strain 93 and a comparison to those of the prototype RPL12-derived GAL virus, strain 93 may be tentatively classified as a member of the avian subgroup of the adenoviruses, distinct from the prototype strain.