Combination of butyrate and active 1, 25 D3 attenuates the severity of Salmonella colitis in mice. First, 6–8-week-old female C57BL/6 mice (Charles River, Boston, MA, USA) were bred and housed under specific-pathogen-free conditions in the animal facility of the Center for Cellular and Biomolecular Research, Kaohsiung, Taiwan. Mice were fasted for 3 h and then orally administered 20 mg of streptomycin. Twenty-one hours after streptomycin treatment, mice were again fasted for 3 h and then orally infected with 108 CFU of SL1344 (ST). Before infection, oral gavage with vehicle control (5% dimethyl sulfoxide), butyrate 20 or 100 mg/kg mice (BT20 or BT100) or 1α, 25(OH)2D3 (VD) treatment (1,25D3, 0.2 µg/25 g mouse) daily for 14 days was undertaken. Loss of body weight (a) and diarrhea situation scores (b) of mice were recoded daily. Cecum was resected and fixed in formaldehyde, and sections were stained with hematoxylin and eosin stain. (c) Representative histological images (×20 and ×50 magnification) of cecum from the different experimental groups. (d) The pathological scores (Supplementary Materials) for colitis in the cecum of mice. The data shown are means ± SEM (n = 7 mice/group). *, p < 0.05.