Aim To study the effects of different observation time and liquid exchange frequency on zebrafish model and optimize the evaluation model. Methods De-membrane zebrafish embryos of 6 h fertilization were exposed for 5 days and changed solution for 4/5 every 24 hours. The mortality rate was measured during the experiment, and the autonomous activity, morphological development and bone development of young fish were detected at the end of the experiment. Meanwhile, the experiment was carried out for 7 days too...