Streptozocin-induced pancreatic islet destruction in beef cows

Streptozocin (STZ) induces diabetes mellitus in sheep and pigs. To test the effect of STZ in cattle, cows were given 75-150 mg STZ per kilogram of body weight. Cows receiving 150 mg/kg required euthanasia within 24 hours after infusion because of the severe systemic effects of STZ. Seven cows receiving doses of < or = 100 mg/kg had mild to marked decrease in islet immunoreactivity for insulin and in pancreatic islet density and mild to severe tubulointerstitial nephritis. Two cows receiving 75 and 85 mg/kg STZ regained their ability to produce insulin and return blood glucose to basal levels. One cow given 100 mg/kg STZ developed insulin insufficiency consistent with type I diabetes mellitus. These findings demonstrate the susceptibility of the bovine pancreas to STZ: however, severe systemic complications were encountered. Alternative dosages and methodologies should be considered in future attempts to induce diabetes in cattle using STZ.