Korean Journal of Agricultural Science ISSN:2466-2402(Print) 2466-2410(Online) 농업과학연구

The purpose of this study was to investigate the safety of Houttuynia cordata Thunb extract (HCE) in Institute of Cancer Research (ICR) mice, to determine the effects of the extract on the growth performance and colony count, and to establish the optimal concentration of HCE. In total, 60 fiveweek- old male ICR mice with an average initial body weight (BW) of 27.24 ± 0.44 g were used in a fourweek experiment. Mice were randomly allotted to four treatment groups (five replications per group, three mice per cage): 1) a control (CON) group fed with normal distilled water; 2) treatment group 1 (T1) fed with normal distilled water containing 0.05% HCE; 3) treatment group 3 (T3) fed with normal distilled water containing 0.1% HCE; and 4) treatment group 3 (T3) fed with normal distilled water containing 0.2% HCE. BW, feed intake (FI), and water intake were measured on the first, fourteenth, and eighteenth days. T2 showed a significant improvement (p < 0.05) in the feed conversion ratio (FCR) over the experimental period. However, water intake levels did not show significant differences among the groups. In the large intestine and feces, E. coli and Lactobacillus levels were significantly improved (p < 0.05) in the HCE treated group compared to the CON group. Supplying HCE via the drinking water improved the growth performance and colony count in ICR mice. Based on results of this study, utilizing HCE in livestock species is expected to be safe and feasible.