Before the ETEC challenge, no clinical sign was observed in the mice of any experimental group. After the ETEC challenge, only one mouse from the ETEC group presented with mild diarrhea, whereas most of the mice initially became dull and depressed and then lost weight. All groups showed no significant difference (P > 0.05) in body weight gain throughout the entire trial period (Figure 1). However, the mice given L. plantarum gained more body weight than those by others. After ETEC challenge, the ETEC, LDLP, MDLP, and HDLP groups presented similar weight changes (Figure 1).