In the present study, the weights and gain ratios in the ETEC group were certainly lower than those of the other groups. However, the growth performance did not significantly change in the mice supplemented with L. plantarum G83 either before or after ETEC infection. This result was similar to those of previous works (Nguyen et al., 2007; Wang et al., 2009, 2016) but can otherwise be explained by the shortage of weight gain evaluation period for weight gain. After ETEC infection, the mice only showed weight loss and slow growth rather than the clear clinical signs of diarrhea and death. Such presentation may be due to the differences in sensitivity of the model animal and in virulence of the strain (Duchet-Suchaux et al., 1990; Porter et al., 2011). These results revealed that the strain did not obviously affect the gain weight within a short period.