The present study evaluated anti-diarrheal effects of a mixture of Coptidis rhizoma, Lonicerae flos, and Paeonia japonica (1:1:1, v/v/v) methanol extracts and dioctahedral smectite (CLPD) on piglet diarrhea caused by Escherichia coli (E. coli) and Salmonella typhimurium (S. typhimurium). Diarrhea index of group 1 administered by 0.5% CLPD mixed with feed, decreased with the passage of time and was insignificantly differed compared to that of control. In group 2 administered by 1.0% CLPD mixed with feed, diarrhea index was significantly decreased compared to that of control and group I during overall experimental periods (P<0.05). After administration of CLPD mixed with feed, the number of E. coli and S. typhimurium in piglet feces of group 1 except for the 1st day was significantly decreased compared to that of the control group (P<0.05), and the number of E. coli and S. typhimurium in piglet feces of group 2 except for the 1st day was significantly decreased compared to that of the control group and group I (P<0.05). This study showed that CLPD had anti-diarrheal effect on E. coli and S. typhimurium causing diarrhea in piglets. CLPD could be an effective candidate for the treatment of enteric bacterial infections in piglets.

Key words: Anti-diarrheal effect; Dioctahedral smectite; E. coli; Korean traditional herbal; extracts; S. typhimurium