Efficacy of live JXA1-R vaccine against PRRS in pig raising farm for meat

Abstract

The objective of this study aimed at evaluating immune response of pig after 30 days-old to live JXA1-R vaccine. There were 2 groups of pigs: Control group (without vaccination) and Vaccination group (at 33 days-old). Immune response to vaccine was assessed by measuring S/P value (ELISA) and neutralizing antibody (NA) titer (OIE, 2010) of pig at 28, 60, 90 and 120 days after vaccination. The studied result showed that there was no significant sign-effect in the vaccinated pigs. Immune response (antibody content) of the pigs in the vaccination group was higher than that of the pigs in the control group (the pigs in this group infected with field virus only). S/P antibody level of the vaccinated pigs increased higher in comparison with antibody level of the control pigs and this value was higher when the vaccinated pigs were infected with PRRS virus before that. However, vaccination has made increasing titer value, but neutralizing antibody titer was not effected in the situation of farms where PRRSV were circulating prior. During the growing period, the vaccinated pigs were less suffered with diseases (diarrhea, respiratory problems, and arthritis) in comparison with the control pigs. The lesion scores on the lung of the vaccinated pigs were reduced significantly. It is recommended that, live JXAI-R vaccine can be used for the piglets at one month old in the farms having HP-PRRS virus circulation.