Isolation of group A swine rotaviruses displaying atypical electropherotypes.

Swine rotaviruses displaying distinctive electropherotypes were isolated from the feces of diarrheic piglets in two swine herds in the province of Buenos Aires, Argentina. In one case all samples isolated showed abnormal electropherotypes. All samples were classified as group A reactive when assayed by an enzyme-linked immunosorbent assay. Three samples from this herd were adapted to grow in tissue culture. The electrophoretic pattern of the genomic RNA as well as the group A reactivity of one of these viruses was retained after cloning in MA-104 cells. In the other pig unit were found samples displaying both classical and abnormal electropherotypes. These viruses were also positive in the enzyme-linked immunosorbent assay; however, since they could not be adapted to grow in tissue culture, this classification must be considered tentative. The abnormal electropherotype exhibited by these pig viruses strongly resembles those of human origin called super short.