Comparative Test on the Immune Effects on Piglets of Inactivated PRRS Vaccines (NVDC-JXA1 Strain) from 3 Manufacturers

[Objective] The aim was to study the immune effects of inactivated PRRS (Porcine Reproductive and Respiratory Syndrome)vaccines (NVDC-JXA1 strain). [Method] The NVDC-JXA1 strains from 3 manufacturers were selected to immunize 28-90 days old piglets so as to observe the immune stress response and monitor the antibody changes. [Result] The side effect of immunization was less and there was no allergic symptom appeared in the piglets immunized by vaccines from different manufacturers. The antibodies were detected from the piglets immunized by Tianbang vaccines from Nanjing and Jiyu vaccines from Inner Mongolia after 14 and 90 d and that were detected from the piglets immunized by Yibang vaccines from Zhejiang after 14 and 60 d. The maintaining time of antibody was 15-30 d. The same day old piglets immunized by normal and doubling doses of vaccines from the same manufacturer had no significant difference on the positive rate of antibodies. The detected positive rates of antibodies from different immunization days old piglets were different, the antibodies generated earlier in the piglets older than 55 d, with higher positive rates. [Conclusion] The study provided reference for the selection of PRRS vaccines in Anhui area.