Penitrem A intoxication of calves: blood chemical and pathologic changes.

An isolate of Penicillium puberulum, obtained from moldy silage, was found to produce a tremorgenic mycotoxin, penitrem A. Dried ground mycelium of this isolate was administered orally to calves either in increasing daily doses or in a single dose that equalled the amount given over a 3-day period in the increasing daily-dose schedule. Signs of intoxication included tremor, ataxia, muscular rigidity, and convulsive episodes. Marked increases in plasma concentrations of lactic acid, pyruvic acid, glucose, and creatine phosphokinase activity were found coincident with the development of severe tremor. The only gross or microscopic change observed in tissues of intoxicated animals was an accumulation of fat in the liver. Changes in the various plasma constituents were interpreted as a secondary effect of the intoxication.