Assessment of the toxicity of a pesticide with a two-generation reproduction test using Daphnia magna.
Daphnia magna (F0 generation) were exposed during 21 days to different diazinon concentrations. Offspring (animals from the first and third brood: F1 (1st) and F1 (3rd), respectively) were transferred to a free pesticide medium during a 21-day recovery period. The algae Nannochloris oculata (5x10(5) cells/ml) were used as food. In this recovery study, survival, growth and reproduction (mean total young per female, mean brood size, onset of reproduction and mean number broods per female) were assessed as individual parameters, and the intrinsic rate of natural increase (r) as population parameter for F1 (1st and 3rd broods) daphnids. Reproduction as well as survival was still reduced in F1 (1st) generation daphnids from parentals (F0) exposed to the highest diazinon concentration. However, F1 (1st) and F1 (3rd) individuals from parentals exposed to pesticide concentrations below 0.5 ng/l were able to restore reproduction and survival when a recovery period of 21 days was allowed.
Sánchez
M
M
Department of Animal Biology (Animal Physiology), Faculty of Biological Sciences, University of Valencia, Spain.
Ferrando
M D
MD
Sancho
E
E
Andreu
E
E
D000818:Animals; D003470:Culture Media; D003621:Daphnia / Q000187:drug effects* / Q000502:physiology; D003976:Diazinon / Q000633:toxicity*; D007306:Insecticides / Q000633:toxicity*; D012098:Reproduction / Q000187:drug effects; D018675:Toxicity Tests
D003470:Culture Media; D007306:Insecticides; D003976:Diazinon