Cloacal inoculation with the Connecticut strain of avian infectious bronchitis virus: an attempt to produce nephropathogenic virus by in vivo passage using cloacal inoculation.

Avian infectious bronchitis virus (IBV) strain Connecticut A-5968 isolated from respiratory tissue of chickens in USA in the 1960s, is considered as representative of respiratory disease causing IBV strains. Specific pathogen free chicks inoculated with the strain via the cloaca replicated the virus more rapidly in their kidneys than did chicks inoculated with the same virus intratracheally. Virus passaged thirteen-times via the cloaca caused stronger nephrotropism and nephropathogenicity than the parent virus. It is suggested that cloacal inoculation of IBV provides new and interesting information concerning the mechanisms of nephropathogenicity of IBV which has became increasingly important worldwide during the last ten years.