The animals were randomly divided into five groups of 18 mice each. Each group was given different treatments as follows: (1) oral administration of sterile PBS from day 1 to day 15 (CONT), (2) oral administration of sterile PBS from day 1 to day 14 followed by oral challenge with ETEC on day 15 (ETEC), (3) oral administration of low-dose L. plantarum G83 (5.0 × 108 cfu mL−1) from day 1 to day 14 followed by oral challenge with ETEC on day 15 (LDLP), (4) oral administration of intermediate-dose L. plantarum G83 (5.0 × 109 cfu mL−1) from day 1 to day 14 followed by oral challenge with ETEC on day 15 (MDLP), and (5) oral administration of high-dose L. plantarum G83 (5.0 × 1010 cfu mL−1) on day 1 to day 14 followed by oral challenge with ETEC on day 15 (HDLP). Simultaneously, individual body weights were recorded daily.