The Use of Polyacrylamide Gel Electrophoresis of Virus RNA in the Study of Rotavirus Infections

Abstract

Polyacrylamide gel electrophoresis of rotavirus RNA has been used to provide diagnostically and epidemiologically useful information about avian and mammalian rotavirus infections. (1) Rotaviruses possessing four different electropherotypes were detected in a longitudinal survey of a 34,000 bird broiler flock. Two of these had not been described previously in chickens. When virus recognisates were grouped according to electropherotype, infection with different electropherotypes was seen to occur in waves, with each wave lasting about one week. Cross-immunofluorescence indicated that rotaviruses with different electropherotypes were antigenically distinct, with only one sharing an antigen with conventional mammalian rotaviruses. (2) Mich intra-species variation was observed when bovine and porcine rotavirus RNAs obtained from different farms were analysed on high resolution 12.5% polyacrylamide gels. Consistent differences were observed between bovine and porcine rotavirus RNA profiles. The detection of additional bands in some RNA profiles indicated that more than one population of rotavirus was present in some faeces specimens. The finding that only one electropherotype was observed in samples taken from heifer calves from a “closed” dairy farm over a 16 month period suggested that only one rotavirus was present and that its genome was electrophoretically stable. (3) One electrophoretically “atypical” recognisate was observed out of 70 samples from bovine or porcine clinical cases.