Study on immune response of pigs vaccinated with Hanvet 1.vn PRRS attenuated virus vaccine

Abstract

The research on immune response of the pigs after vaccination with Hanvet1.vn PRRS attenuated virus vaccine was carried out at Hanvet company. The changes of neutralising antibody and antibody were determined by the IPMA method. The studied result showed that 7 days after vaccination, antibody appeared and reached the highest content in the 5th week after vaccination (1/4888.7), then the antibody content decreased in the 6th month, remaining 1/463.13 only. Neutralising antibody appeared later, 4 weeks after the vaccination, and reached the highest titre at the 11th week after vaccination (1/21.11) then it was decreased. Up to the 5th month after vaccination, the neutralising antibody content remained only ¼ and then the antibody content was not capable to protect the pigs in the 6th month after vaccination. The piglets were born from the sows vaccinated with Hanvet1.vn PRRS vaccine, they received antibody through colostrum. The antibody content in the blood of the piglets reached the highest level at the 1st day after birth (1/1835,46 with IPMA and 1/8.46 with neutralising antibodies). Then antibody content in the blood of piglets decreased rapidly. Up to the 14th days after birth, antibody content in the blood of piglets reached 1/676.49 (IPMA) and 1/4.11 (neutralising). The piglets at 4-weeks-old presented the best immune response after the vaccination.