EFFECTS OF NEONICOTINOID INSECTICIDE ACETAMIPRID ON SWIMMING VELOCITY, HEART RATE AND THORACIC LIMB MOVEMENT OF DAPHNIA MAGNA

摘要

Little is known on the effects of nicotinoid pesticides on behavioural and physiological parameters of microcrustaceans. The aim of the study was to determine the effects of three concentrations (25,50 and 100 mg l~(-1)) of neonicotinoid insecticide Mospilan 20 SP (containing 20% of the active ingredient acetamiprid) on swimming velocity and physiological parameters such as heart rate and thoracic limb activity in Daphnia magna. The results showed that acetamiprid induced concentration-dependent inhibition of swimming velocity and thoracic limb activity after 2 hours of the exposure. The insecticide depressed the heart rate at 100 mg 1_1 after 24 hours of the exposure, however stimulation was noted at 25 and 50 mgl~(-1). The study suggests that neonicotinoids may alter on behavioural and physiological parameters in Daphnia magna thereby increasing susceptibility of these animals to higher predator pressure.