ABSTRACT
This chapter addresses the issue of what factors within the digestive tract may regulate colonization of the piglet small intestine by fimbriated enteropathogenic E. coli. Most of the host’s digestive and absorptive activities are located in the small intestine and their efficiencies are closely related to the available surface area of the intestinal epithelium. Porcine ETEC (enterotoxigenic E. coli) possessing K88 fimbriae play a major role in diarrheal diseases in piglets. The regulation of the expression of fimbriae is influenced by a number of environmental parameters such as temperature, pH, nutrients, and growth rate of the bacteria. The interactions between the indigenous microbiota and pathogens have been referred to as bacterial antagonism, bacterial interference, and colonization resistance. It is interesting to note that stationary phase cells of E. coli 1107 expressed considerably more K88 fimbrial protein when grown in ileal mucus as compared to control cells grown in laboratory media.
