MODEL FIELD STUDY OF SUMITHION 50 EC AND FUSILADE S ON PHEASANTS
Toxicological studies on wild animals play an important role in the eco-toxicological examination of pesticides. The applied model tests enable the as-sessment of toxicological consequences with particular regard to the life and nu-trition of wild animals in the ploughed field among
plants treated with pesticides. The application of different pesticide formulations on plough-land may pose a si-multaneous chemical burden to wild birds. In this model study, manifestations of the interaction between an insecticide and a herbicide were studied in pheasants. The birds were
placed on lucerne in cages (48 m 2 ) and sprayed once. The applied doses were: Sumithion 50 EC 1 litre/ha + Fusilade S 6 litres/ha (practical doses) and Sumithion 50 EC 5 litres/ha + Fusilade S 30 litres/ha. The analytically deter-mined pesticide concentration of the lucerne was taken as a
basis in the further treatment of fodder. The fodder of pheasants contained the following chemicals: 85 mg/kg Sumithion 50 EC + 510 mg/kg Fusilade S and 425 mg/kg Sumithion 50 EC + 2250 mg/kg Fusilade S. Sporadic deaths observed among the pheasants were of traumatic origin and not due to a
toxic effect. The decrease of body weight was significant only at the higher dose levels. Acetylcholinesterase (AChE) activity of the blood decreased significantly in both dose groups. On the basis of the results obtained it can be established that at the dose level used in the practice the
pesticides studied do not give rise to a toxic interaction in pheasants.