Figure 2. BUT was 19.79±2.39 s in normal control rabbits and was reduced to 11.75±0.51 s at 2 weeks’ pregnancy, 14.9±0.65 s at 3 weeks, and 12.43±0.31 s at 4 weeks pregnancy. Each time point of pregnancy was significantly lower than that of normal control (p<0.05, as indicated by *). Data are presented as mean±SEM.