Effects of nutritional renewal frequency on survival and reproduction of Ceriodaphnia dubia

Different renewal diet frequency procedures of Ceriodaphnia dubia were evaluated with different culture stages: intervening cultures and pilot tests (equivalent to controls in a classical toxicity test). A series of control experiments was conducted on over three generations to estimate historical culture influence and effects of different renewal frequencies in five different factorial designs performed at different times. The criteria to assess health of culture were survival and reproduction. Nutritional deficiency was not found during this study, but renewal frequency has an obvious effect on the reproduction. This study further establishes that a medium slightly different than those recommended by the U.S. Environmental Protection Agency can successfully work for culturing and testing C. dubia.