Oosporein-toxicosis in the turkey poult.

Turkey poults were fed diets containing oosporein at concentrations of 0, 500, 1,000, and 1,500 micrograms/g from hatching until three weeks of age. Low feed consumption resulted in poor growth rates at every dietary level of oosporein; however, a dose-related increase in water consumption was observed. The most significant effect of dietary oosporein was severe visceral and articular gout, with death ensuing in 24 and 52% of the poults at the 1,000 and 1,500 micrograms/g levels, respectively. Gout and mortality were absent at 0 and 500 micrograms/g. In addition to tissue urate deposition, necropsies revealed dehydration, swollen pale kidneys, hemorrhagic proventriculitis with mucosal necrosis, gizzard enlargement and lining discoloration, an increase in gall bladder size, and focal hepatic necrosis. The relative weights of the kidney, liver, proventriculus, gizzard, and pancreas were increased in a dose-related fashion; spleen and bursa weights were unaffected. Among plasma constituents, uric acid, urea, and the activities of glutamic-oxalacetic transaminase and lactic dehydrogenase were elevated in response to dietary oosporein; albumin, potassium, phosphorus, and calcium were decreased. The toxin had no effect on plasma total protein, sodium, glucose, cholesterol, triglycerides, alkaline phosphatase, or creatine phosphokinase. These data substantiate the original classification of oosporein as a nephrotoxin and etiologic agent of gout in avian species.