Chronic effects of Cd on the reproduction of the guppy (Poecilia reticulata) through Cd-accumulated midge larvae (Chironomus yoshimatsui).
Chronic effects of Cd on the growth and reproduction of the guppy (Poecilia reticulata) were studied using a food chain model, midge larvae as prey and guppy as predator. The transfer rate of Cd from the midge to the guppy was between 0.5 and 1% during the 30-day experiment. Growth rate of the guppy fed Cd-accumulated midge larvae (270 micrograms/g dry wt) for 30 days was not impaired. Cumulative numbers of fry produced by the guppy fed Cd-accumulated midge larvae (210 micrograms/g) for 2 months decreased to ca. 80% of the control. Guppies had been fed the Cd-accumulated midges from 30 days old for 7 months. Cumulative numbers of fry produced by the guppy fed midge larvae-accumulated 500, 800, and 1,300 micrograms Cd/g for 6 months decreased to 79, 65, and 55% of the control, respectively. Similar effects of Cd on the reproduction of guppy were shown between the guppies fed the Cd-accumulated midge larvae (500 micrograms Cd/g) and exposed to 10 or 20 micrograms Cd/liter for the 6 months. The Cd concentrations of the digestive tract, liver, and kidney increased strongly, indicating that such Cd accumulation was brought on mainly through the Cd-accumulated midges. Mortality of the female guppies fed larvae-accumulated 1,300 micrograms Cd/g increased abruptly from the 6 months of the experiment, whereas no male guppy died during the experiment.
Environmental Biology Division, National Institute for Environmental Studies, Ibaraki, Japan.
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Hatakeyama
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Yasuno
D000284:Administration, Oral; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002104:Cadmium / Q000493:pharmacokinetics* / Q000633:toxicity; D004625:Embryo, Nonmammalian / Q000187:drug effects; D005260:Female; D008297:Male; D011036:Poecilia; D012098:Reproduction / Q000187:drug effects; D014873:Water Pollutants / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
D014873:Water Pollutants; D014874:Water Pollutants, Chemical; D002104:Cadmium