Institution: | * Istituto di Malattie Infettive, Profilassi e Polizia Veterinaria, dell'Universita' di Perugia, Perugia, Italy ? Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia, Brescia, Italy ? Centro Provinciale Svezzamento Vitelli, Tripoli, MN, Italy § Istituto di Tecnica delle Autopsie e Diagnostica Cadaverica, dell'Universita di Perugia, Perugia, Italy ¶ Istituto Superiore di Sanita', Roma, Italy |
Abstract: | Four cytopathic strains (81/32F, 81/36F, 81/40F, 82/80F) of bovine rotavirus were shown to be pathogenic for conventionally reared newborn calves. Calves were infected orally, using 3 calves for each isolate. All became febrile, were depressed and diarrhoeic. Two calves, one of which in the group of those infected with 81/36F isolate, and the other infected with strain 81/40F, were killed when moribund. A 3rd calf from the 81/36F infected group, died. At necropsy localized lesions of the small intestines, which are considered to be typical of rotavirus infection, were found. Virus was consistently isolated from the fecal samples of the inoculated calves up to 13 days post-inoculation. It was speculated that some differences existed in the virulence of the bovine rotaviruses tested. The cross protection tests revealed that 1 strain (81/36F) might be antigenically more complex than the others. |