Rice culture of Aspergillus ochraceus that contained ochratoxin A or pure crystalline ochratoxin A was administered orally daily to 23 young male Beagle dogs. Six other young male Beagles served as controls. Most dogs were killed in extremis on or before day 14 after receiving a daily oral dose of ochratoxin A, 0.2–3.0 mg/kg body weight. Consistent clinical features of the mycotoxicosis were anorexia, weight loss, emesis, tenesmus, passage of clots of blood-stained mucus from the rectum, rectal temperature up to 107°F, tonsillitis, dehydration and prostration. The prominent clinicopathological features of the toxicosis were a reflection of renal damage. The urine had a specific gravity as low as 1.004 and contained granular casts, necrotic renal epithelium, and concentrations above normal of protein, glucose, lactic dehydrogenase, isocitric dehydrogenase, leucine aminopeptidase, glutamic-pyruvic transaminase, glutamic-oxalacetic transaminase, and alkaline phosphatase. Serum concentrations of these enzymes did not change. Concentrations of blood urea nitrogen remained, with two exceptions, within the normal range, but the concentrations of blood glucose declined terminally. Serum concentrations of the liver-specific enzyme, γ-glutamyl transpeptidase and sulfabromophthalein dye retention time did not indicate hepatic dysfunction.
Production of Ochratoxin A by Aspergillus ochraceus Isolated in Japan from Moldy Rice