The present study was conducted to investigate the effects of oral inoculation of Enterotoxigenic E. coli (ETEC: N5 strain, 1×1011CFU) and subcutaneous injection of rBoGM-CSF (rBoGM-CSF: 8μg/kg) on neutrophil chemiluminescence (CL) activity of peripheral blood in newborn Holstein calves. All animals inoculated with ETEC showed diarrhea within 24 hr after the inoculation. The neutrophil CL activity markedly declined from 6 hr to 3 days following the inoculation of ETEC. The decline in neutrophil CL activity preceded the generation of diarrhea. The administration of rBoGM-CSF controlled the decline in neutrophil CL activity. (Pathophysiology Section, Department of Production Diseases TEL +81-298-38-7810)
