Rotavirus is not a new pathogen; however, there is evidence of re-emergence as noted by the increased diagnoses at multiple diagnostic laboratories. New testing modalities (PCR) have been developed to detect different serogroups of rotavirus in diseased or diarrheic pigs; however, interpretation of test finding is difficult because the basic research comparing these different serogroups has not previously been done. With this research we compared fecal shedding and intestinal pathology of naïve pigs inoculated with serogroups A, B, or C singularly and in all combinations of coinfections. This was accomplished by successfully cultivating serogroup C rotavirus in cell culture and purifying serogroup B rotavirus for experimental inoculation. Generated data from this research indicates all serogroups are able to cause clinical diarrhea and intestinal pathology by 24 hrs post-infection (hpi) with fecal shedding as early as 12 hpi. Serogroups B and C infection resulted in diffuse small intestinal pathology at 24 hpi, while serogroup A infection preferentially damaged the jejunum in the early phase of disease. Serogroup coinfections were not more severe than singular infections in this study, but serogroup C virus was more frequently detected in feces when in combination with other serogroups. Alternatively, serogroup B was less frequently detected when in combination with another serogroup. In summation, the current study shows that all rotavirus serogroups are capable of causing diarrhea and intestinal lesions when given alone or in different combinations.
Iowa State University, Veterinary Diagnostic Laboratory
1600 South 16th
Ames, IA 50011