Abstract: To compare the humoral immune effects of three kinds of oil-adjuvant emulsified inactivated vaccine, ninety one pigs of 51-day-old were randomly divided into healthy control group or AA, BB, CC, AAA, BBB and CCC groups which were inoculated with A, B or C vaccine with two or three times, and booster inoculation was conducted every 4 weeks post inoculation (WPI). Blocking ELISA was applied to detect specific antibody blocking rates at 2, 4, 6, 8, 10 and 12 WPI, respectively. The results showed that the antibody blocking rates of inoculated group AA, BB and CC were peaked at 8WPI, i.e. 60.1%, 39.0% and 45.2%, and antibody levels were declined sharply since 8 WPI, the corresponding antibody blocking rates were 19.7%, 25.2% and 31.0%, respectively; while the antibody blocking rates of AAA, BBB and CCC had been increased gradually since 8 WPI, the corresponding antibody blocking rates were 46.3%, 48.1% and 50.1%, and antibody positive rate of each one were no less than 46%, taking together, the humoral immune effects order of six inoculation group was 46.3%, 48.1% and 50.1%.

Key words: swine; foot and mouth disease type O; oil-adjuvant emulsified inactivated vaccine; humoral immune effects