Effects of Antibiotics on Daphnia ∗,†

Abstract

Summary

1. The survival of Daphnia following exposure to varying concentrations of chemotherapeutic agents was studied. 2. The toxicity of the antibiotics for Daphnia in terms of survival showed a correspondence to their acute toxicity for man, in terms of untoward reactions. 3. An apparently specific pharmacological action of neomycin on the gut of Daphnia is described. 4. The oxygen consumption of Daphnia was found to be about 5 × 10⁻² μl per μg N per hour. The rate was not altered following addition of 10 μg/ml of streptlomycin. 5. The use of Daphnia as a test animal for screening antibiotics is considered.