Dietary regimen, rotavirus, and hemolytic enteropathogenic Escherichia coli in weanling diarrhea of pigs.

Previously, we induced weanling diarrhea in piglets by infecting them first with rotavirus followed by a hemolytic enteropathogenic Escherichia coli. We postulated that rotavirus, by damaging the epithelium of the small intestines, produced an entero-environment which favored the selection and growth of the enteropathogenic E. coli. Furthermore, diet might affect the entero-environment and influence the course of the disease. To test this, newly weaned 3-week-old piglets were assigned to one of four dietary regimens and infected with rotavirus followed 24 h later with an enteropathogenic E. coli. The course of the disease was followed by monitoring the severity of diarrhea, and the fecal shedding of rotavirus and the enteropathogenic. E. coli in these dually infected piglets. The dietary regimen designed to tax the digestive and absorptive capacity of the piglet (high nutrient intake fed 3 times a day) produced the most prolonged diarrhea, colonization of gut by the hemolytic enteropathogenic E. coli and persistent shedding of rotavirus. The same nutrient intake divided into 24 equal increments and fed hourly produced a less severe response. The least response was seen in piglets fed one-third the nutrient intake either hourly or 3 times a day. We conclude that dietary regimen plays an important role in rotavirus-Escherichia coli induced weanling diarrhea.