TOXICITY OF THE CRYSTALLINE POLYPEPTIDES OF BACILLUS-THURINGIENSIS SUBSP ISRAELENSIS IN JAPANESE-QUAIL

The solubilized parasporal crystalline proteins (SPCP) of Bacillus thuringiensis subsp. israelensis when administered to Japanese quail by intraabdominal (IA) injection were toxic with an LD50 at 24 hr of 22.8 mg/kg. No deaths were noted by intranasal, subcutaneous, and intravenous administration. SPCP were highly hemolytic against quail red blood cells but this SPCP-induced hemolysis was inhibited by preincubation of SPCP with quail serum. Electrocardiographic analyses of IA-injected quail demonstrated cardiac dysfunction consistent with bradycardia. Hypothermia was also positively correlated with heart rate reduction. SPCP IA injection reduced serum lipid levels and alkaline phosphatase, and increased serum glucose, creatine phosphokinase, and lactate dehydrogenase. Induction of a septic shock-like condition may be the toxic mode of action of IA-injected SPCP in Japanese quail. © 1992.