Acute oral toxicity of the herbicide BUREX EKO in pheasants

The aim of this study was to determine the acute LD50, clinical symptoms and pathological changes of acute BUREX EKO intoxication in pheasants according to OECD No 205. Medium lethal dose (LD50) of BUREX EKO in pheasant is 3.84 ml/kg body weight with the upper level of reliability 4.50 ml and lower level of reliability 3.27 ml/kg body weight. As far as the calculation to the effective substance is concerned it is 1077 mg of chloridazone per kg body weight with the interval of reliability from 919 to 1263 mg/kg body weight. Calculated the effective substance of chloridazone (3.84 ml is LD50 of BUREX EKO which contains 1077 mg of chloridazone) BUREX EKO can be classified as the moderately toxic substance to pheasants. There were following clinical symptoms of the BUREX EKO intoxication in pheasants: apathy, drowsiness, incapability to move, ruffled feathers, slight diarrhoea, strenuous respiration, tonico-clonical cramps before death, decease with the head expressively bent rearwards. There was a relatively fast beginning of rigor mortis in dead pheasants. Pathologico-anatomical dissection of the pheasants obtained under conditions of acute intoxication did not reveal any changes on the organs of both experimental and control pheasants which would be immediately connected with the effect of the administered substance. Hyperaemia was recorded by histologico-pathological investigation of the liver and kidneys. No changes on the brain and intestine wall were recorded.