Gnotobiotic Piglets Experimentally Infected with Neonatal Calf Diarrhoea Reovirus-Like Agent (Rotavirus)

Abstract

Abstract. Gnotobiotic piglets were infected with a strain of rotavirus that had been isolated from a calf and passaged four times in piglets. The resulting disease was studied by light and electron microscopy at 21,44 and 68h after inoculation. In thesmall intestine infection caused desquamation of the epithelial cells of the villi resulting in severe stunting. There was severe damage to microvilli and accumulation of lipid within the cytoplasm. Virus particles were seen in epithelial cells covering the stunted villi. Infection also caused desquamation of the superficial epithelial cells of the stomach mucosa and of the epithelial cells of the bronchi, bronchioles, and alveoli of the lungs. The reovirus-like particles, which have been seen in faeces of young children with acute nonbacterial gastroenteritis, have been found to be morphologically indistinguishable from those of neonatal calf diarrhoea [8, 101. The calf and human viruses also appeared morphologically and antigenically distinct from both reoviruses and orbiviruses, and the term rotavirus has been proposed [7-91.Although the calf and human rotaviruses are morphologically indistinguishable, we were unable to infect calves with human virus. Piglets, however, are susceptible to infection with human virus [5] but do not become ill. We passed calf rotavirus serially five times in gnotobiotic piglets, and each passage produced profuse diarrhoea, depression and anorexia. Our serological studies have shown that pigs are naturally infected either with calf

Antigenic and Pathogenic Relationships of Three Bovine Rotaviruses and a Porcine Rotavirus

“…It should be noted that the properties attributed to the faecal bovine rotaviruses referred to by Woode et al (1974), Woode (1975) andHall et al (1976) were due to a mixture of antigenically and pathogenically different viruses, some of which are described in this paper. It is possible that, as rotaviruses have segmented genomes, genetic reassortment, either before or after passage in experimental animals, had occurred between the viruses.…”

Variation in virulence of bovine rotaviruses

“…It originated from an outbreak of diarrhoea in cattle, was pathogenic for pigs at the first passage (Hall et al 1976) and was found to be related antigenically to both bovine and porcine rotaviruses . On subsequent serial passage of the faecal PP-1 from gnotobiotic pigs in calves, it was avirulent but its pathogenicity for calves may have been modified by passage in pigs.…”

Pathogenesis of an attenuated and a virulent strain of group A human rotavirus in neonatal gnotobiotic pigs

“…However, detailed pathogenesis studies of HRV infection in animals are few and limited to virulent HRV strains (Gouvea et al, 1986;Mebus et al, 1977). The reported pathological lesions induced by virulent strains of HRV in animals are similar to those induced by virulent rotaviruses of homologous host origin and include the loss of intestinal absorptive cells and villous atrophy followed by crypt hyperplasia and mucosal epithelium repair (Collins et al, 1989;Hall et al, 1993;Theil et al, 1978;McAdaragh et aI., 1980;Castrucci et al, 1983;Snodgrass et al, 1977;Adams & Kraft, 1967;Pappenheimer & Enders, 1947;Hall et al, 1976;Pearson & McNulty, 1977;Crouch & Woode, I978).…”

“…The group A rotaviruses cause mild asymptomatic infection to severe life-threatening diarrhoea in susceptible hosts (Greenberg et al, 1994;Saif, 1990 b). Variations exist in prevalence and virulence among the group A rotaviruses which may account for the spectrum of disease observed among natural hosts (Collins et al, 1989, Greenberg et al, 1994Hall et al, 1976;Theil, 1990).…”

“…Rotaviruses are generally considered to be host-specific although under experimental conditions several animal species have been infected with rotaviruses from heterologous species origin (Greenberg et al, 1994;Gouvea et aI., 1986;Hall et al, 1976;Schaller et al, 1992;Steel & Torres-Medina, 1984;Wyatt eta]…”