Villarroel M J, Ferrando M D, Sancho E, Andreu E
Department of Animal Biology (Animal Physiology), Faculty of Biological Sciences, University of Valencia, Dr. Moliner 50, Burjasot, Valencia, E-46100, Spain.
Ecotoxicol Environ Saf. 1999 Sep;44(1):40-6. doi: 10.1006/eesa.1999.1817.
The feeding behavior of the cladocera Daphnia magna subjected to a short-term exposure to the acaricide tetradifon (4-chlorophenyl 2,4, 5-trichlorophenyl sulfone) was studied. The experiments were performed using the unicellular algae Nannochloris oculata at a density of 5x10(5) cells/ml as food for the organisms. In a first experiment, three generations (F0, F1, and F3) of the daphnids were exposed to sublethal levels of tetradifon (0.1, 0.18, 0.22, and 0.44 mg/l) and the effect of the toxicant on filtration and ingestion rates was determined. Rates of filtration and ingestion of D. magna declined in the three generations studied with increasing toxicant concentrations; however, toxicant effect was greater in daphnids from generations F1 and F3 than in those from the parental generation F0. A second experiment was conducted in order to evaluate whether animals of a first (1) or third (F3) generation coming from parental daphnids (F0) previously exposed to those pesticide concentrations exhibited any alteration in feeding behavior when transferred to clean water (recovery period). The results indicated that the feeding rates of D. magna generations F1 and F3 were still affected during the recovery period but to a less degree. The effective tetradifon concentrations D. magna at which feeding rates were reduced to 50% that of controls (EC(50)) were also calculated.
研究了大型溞（水蚤）在短期接触杀螨剂三氯杀螨砜（4-氯苯基 2,4,5-三氯苯基砜）后的摄食行为。实验使用眼点拟微绿球藻作为生物的食物，其密度为 5×10⁵ 个细胞/毫升。在第一个实验中，三代大型溞（F0、F1 和 F3）暴露于亚致死水平的三氯杀螨砜（0.1、0.18、0.22 和 0.44 毫克/升），并测定了毒物对滤食率和摄食率的影响。在所研究的三代大型溞中，随着毒物浓度的增加，滤食率和摄食率均下降；然而，F1 代和 F3 代大型溞受到的毒物影响比亲代 F0 代更大。进行了第二个实验，以评估来自先前暴露于这些农药浓度的亲代大型溞（F0）的第一代（F1）或第三代（F3）动物转移到清洁水中（恢复期）时，其摄食行为是否有任何改变。结果表明，F1 代和 F3 代大型溞的摄食率在恢复期仍受到影响，但程度较小。还计算了使大型溞摄食率降低至对照的 50%时的三氯杀螨砜有效浓度（EC₅₀）。
