A bivalent vaccine consisting of Japanese B encephalitis (JE) live virus and ultravioletinactivated porcine parvovirus (PP) was examined for innocuity and potency in pigs. When injected with the bivalent vaccine, pigs showed no clinical manifestation, but formed HI antibodies against JE virus and PP. The titers of these antibodies were equivalent to those obtained with control monovalent vaccines, indicating that the combined vaccine was available for practical use.
There were no marked differences in the result of parturition among the groups of pigs which had received the bivalent vaccine or either control monovalent vaccine and nonvaccinated antibodypositive control pigs. No potency of the bivalent or control monovalent vaccines was proved on this result, because neither mummification nor malformation occurred to the nonvaccinated control group, and because commn stillbirth was often seen in every vaccinated group.
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