Development of antibodies after foot and mouth disease vaccination in pigs

Three serotypes (O+A+Asia1 type) of the foot-and-mouth disease (FMD) vaccine were injected into cloven-hoofed animals in Korea after the nationwide spread of FMD at the end of 2010. This study was conducted to investigate FMD antibody development after FMD vaccination, and to determine whether there was a significant correlation between the antibody titer of the sow and the antibody titer of the growing pigs. The antibody titer (percentage inhibition [PI] titer) of the sow (gilt) after FMD vaccination was maintained at a level higher than 50 (P<0.05) for 5 months. A higher PI titer for the 1-month-old growing pigs corresponded with greater inhibition of the PI titer of the vaccinated growing pigs (P<0.05). A negative correlation (P<0.05) between the PI titer of the 1-month-old growing pigs and the PI titer of 3-month-old growing pigs, 4-month-old growing pigs after FMD vaccination at 2 months, 3months was identified, with a coefficient of determination ( $R^2$ ) of 0.274. Thus the PI titer of the growing pigs was inhibited to a greater degree when vaccination was performed at 2 months of age than at 3 months. However, many other factors likely influence growing pigs' PI titer in addition to the PI titer of the sow and age at vaccination, given that the coefficient of determination was somewhat lower.