Electrocardiograms of 10 rabbits were anallzed, Inoculated with toxigenic extract produced by Clostridium perfringens type A. (NCTC8798). The extract was rich In enterotoxln and given at a dose of 0.5 m l/kg of body weight. The toxin contained 1.45 m g /m i., of protein. In some cases the E.C.G. showed discrete Imbalance of ST Interval, Incomplete atrioventricular blockage and myocardial Ischaemla. In one of the cases, complete atrioventricular blockage, fibrillation and cardiac failure with subsequent recuperation was observed. Other changes were flattening of wave T and Impairment of wave J; these changes are associated with subendocardial problems and alterations In cardiac repolarlzatlon. The clinical signs observed post-lnoculatlon were: lassitude, serous nasal bilateral secretion, dlsnea and diarrhea.