Perturbations of plasma metabolites correlated with the rise of rumen endotoxin in dairy cows fed diets rich in easily degradable carbohydrates.
Groups of four pregnant ewes were allocated to the following feeding and intravenous endotoxin treatments: fed, Escherichia coli endotoxin (50 micrograms/kg X 75), fed, saline, fasted, E. coli endotoxin (50 micrograms/kg X 75) and fasted, saline. Endotoxin administration resulted in depression, fever, hypoglycemia, hypocalcemia and a reduction in nonesterified fatty acid and ketone body concentrations. Depression correlated best with body temperature (r = 0.76), fasted sheep showed smaller increases in body temperature and were less depressed following endotoxin. Three of eight endotoxin treated sheep died, mortality was not related to rectal temperature but was associated with lactic acidosis. Hypoglycemia was not associated with either death or depression. Fed sheep that were unable to stand had lower serum calcium concentrations than standing sheep.