Studies on orthoreoviruses isolated from young turkeys. III. Pathogenic effects in chicken embryos, chicks, poults, and suckling mice.

The pathogenicity of four clone-purified reoviruses (81-51, 81-68, 81-311, and 82-88) was studied in experimentally infected specific-pathogen-free (SPF) chicken embryos and chicks. SPF and specific-antigen-and-antibody-negative (SAAN) turkey poults, and suckling mice. In SPF embryos, all four viruses caused death or lesions characteristic for avian reoviruses. SPF chicks inoculated orally with isolate 81-68 showed no signs of overt disease but did develop antibodies to reovirus. In some experiments, poults inoculated orally with isolate 81-68 exhibited increased mortality, abnormal feather development, lower body weight gain, and pasted vents. Body tremors, uncoordinated motor movement, and oily hair coats were seen in suckling mice inoculated intracerebrally with isolates 81-51, 81-68, and 82-88. Mice inoculated intracerebrally with isolates 81-68 and 82-88 exhibited retarded growth.