Increased Ruminoreticular Temperature and Body Activity after Foot-and-Mouth Vaccination in Pregnant Hanwoo (Bos taurus coreanae) Cows

How does vaccination against foot-and-mouth disease (FMD) affect pregnant cows? Vaccination is the most effective method of preventing the spread of FMD, but it is linked to sporadic side effects, such as abortion and premature birth, which result in economic loss. In this study, ruminoreticular temperature and body activity were measured before and after FMD vaccination using a ruminoreticular biocapsule sensor in Hanwoo cows at different stages of pregnancy. Compared to the unvaccinated groups, the ruminoreticular temperature increased 12 h after vaccination in the vaccinated groups. This increase in temperature is significantly correlated to vaccination. Compared to the nonpregnant and early pregnancy groups, the ruminoreticular temperature of the late pregnancy group increased sharply by more than 40 °C. Moreover, in nonpregnant and early pregnancy groups, a rapid increase in body activity was observed after FMD vaccinations. Of the 73 pregnant vaccinated cows in the study, a total of five cases had side effects (four abortions and one premature birth). Therefore, changes in the ruminoreticular temperature and activity in pregnant cows can be used as raw data to further clarify the association of FMD vaccination with the loss of a fetus and possibly predict abortion, miscarriage, and premature birth following FMD vaccination.