EFFECT OF ORALLY-ADMINISTERED EPIDERMAL GROWTH-FACTOR ON INTESTINAL RECOVERY OF NEONATAL PIGS INFECTED WITH ROTAVIRUS

The effect of oral epidermal growth factor (EGF) on histological and b iochemical changes in epithelium in the small intestine was studied in colostrum-deprived neonatal pigs. Forty-eight pigs were infected at 4 days of age with 2 x 10(7) plaque-forming units of porcine group A ro tavirus and orally fed a simulated sow-milk diet supplemented with 0.0 , 0.5, or 1.0 mg/L recombinant human EGF. Sixteen noninfected pigs wer e fed a diet without EGF supplementation. Infected pigs developed seve re diarrhea; they also consumed 25% less food and gained 60% less weig ht than noninfected pigs. Pigs were killed 8 days postinfection to col lect samples at seven equidistant points in the small intestine. Rotav irus infection decreased villus height by 37% and reduced specific act ivity of lactase by 54%, of leucine aminopeptidase by 43%, and of alka line phosphatase by 54% in the small intestine, compared with noninfec ted pigs. Only the supraphysiological dose of EGF (1.0 mg/L) consisten tly increased villus height in the proximal and mid-small intestine an d lactase-specific activity in the mid-small intestine of rotavirus-in fected pigs. However, this dose was only partially effective in restor ing intestinal mucosal dimensions and enzyme activities. Supplemental EGF did not hasten the resolution of diarrhea. These data indicate tha t high physiological levels of EGF are beneficial in stimulating recov ery of epithelium in the small intestine following rotavirus infection .