Effect of chloramphenicol on the life table demography of Brachionus calyciflorus (Rotifera): A multigenerational study

During the last two decades, there has been increasing concerns about the presence of antibiotics in aquatic environments. Phenicol antibiotics, such as chloramphenicol (CMP), commonly used in the veterinary and aquaculture fields to treat infections, have been often detected in aquatic environments, but scarce ecotoxicity information regarding the effects of CMP on non-target aquatic organisms is available, and multigenerational studies are seldom studied. Here we quantified the demographic responses of Brachionus calyciflorus exposed to sublethal concentrations (0, 5, 10, 30, 50, 70 and 90 mg L^-1) of CMP for three successive generations (P0, F1, and F2). Our results showed that compared to the control, higher concentrations of CMP significantly decreased the life expectancy at hatching, generation time, net reproductive rate and intrinsic rate of population increase in all three generations, and the proportion of mictic offspring in the F1 generation of B. calyciflorus. With increasing generations, higher concentrations of CMP showed increased toxic effects on life expectancy at hatching and net reproductive rate, but irregular negative effects on generation time, intrinsic rate of population increase, and proportion of mictic offspring of the rotifers. These results indicate that multigenerational studies are necessary to prevent insufficient assessments of the impact of antibiotics in aquatic ecosystems.