Food choice experiments with cadmium nitrate dosed food in terrestrial isopod Oniscus asellus (Crustacea)

Abstract

The influence of different concentrations of cadmium nitrate on food choice behaviour was studied in the terrestrial isopod Oniscus asellus. In paired food choice tests, consumption rates were compared in relation to cadmium nitrate concentrations and duration of feeding. The consumption of contaminated food was reduced at even the lowest cadmium concentration already in the first week offeeding. In the third week the consumption rates for uncontaminated and contaminated food reached a ratio of 6:4 in all animal groups. Consumption of contaminated food during the experiment resulted in increased cadmium content in the animals. It is presumed that 0. asellus cannot distinguish food according to cadmium concentration. The difference in consumption rates between uncontaminated and cadmium-contaminated food could be based on integration of feeding behaviour and the adverse metabolic effects of cadmium.