Objective:To establish the Escherichia coli-infected diarrhea model of suckling Tibetan mini-pigs

in order to study the mechanism of Gegen Qinlian Tang (GQT) on E. coli-infected diarrhea in infants. Method:The mini-pig diarrhea model was established through oral administration with pathogenic E. coli. The animals were divided into control group (Montmorillonite powder

93.5 mg·kg-1)

low-dose group (1.21 g·kg-1)

middle-dose group (6.05 g·kg-1) and high-dose group (12.1 g·kg-1). Fecal E. coli count and white blood cell count were detected after each administration

and the serum tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were detected by enzyme linked immunosorbent assay (ELISA) kit. The diarrhea index

weight change and survival rate were observed. Result:When the dose of E. coli was 1×109 CFU·kg-1

the watery diarrhea was maintained at 6 h

the count of fecal coliform was higher than 1×1011 CFU·g-1

and there was no obvious trend of self-cure. High

medium and low-dose GQT groups showed significant reduction in fecal E. coli count and blood white blood count

and inhibition of the expressions of serum TNF-α and IL-6.Low-dose group showed significant inhibition of diarrhea

and middle and high-dose groups had no obvious antidiarrheal effect. Conclusion:When the dose of E. coli was 1×109 CFU·kg-1

the feces were still watery at 6 h

and the E. coli count of fecal was higher than 1×1011 CFU·g-1

which proved that the E. coli-infected diarrhea mini-pig model was successfully established. GQT could relieve E. coli-infected diarrhea among suckling pigs by resisting inflammation and inhibiting the proliferation of E. coli. The anti-inflammatory effect may be related to the reduction of inflammatory factors TNF-α and IL-6.