A Toxicological Study using Zebrafish (Danio rerio) as a Model

Abstract

Only recently has it been adequately recognized that substances present in the environment can have adverse effects on developing organisms. Now, with environmental pollutants accumulating at an unprecedented rate, and with pharmaceuticals dominating western medicine, it is particularly important that we understand the effects of the substances to which we are exposed. Zebrafish (Danio rerio) has become a widely used model system for the study of vertebrate development. This system is particularly amenable for use in the undergraduate laboratories because of the ease of collection and manipulation and the rapid rate of development. In this lab, students use zebrafish to examine the effects of nicotine, ethanol, and retinoic acid on normal development. Students first examine normal development and compare it to overall growth, dry weight, and behavior of zebrafish exposed to these chemicals. The students may also collect data on LC50 and notochord length. The quantitative data is evaluated for statistically significant differences between treatments. Finally, students write a research proposal for an independent experiment in which they expose embryos to a toxicant of their choice, carry out the experiment, and present their findings. This lab introduces students to the use of animal models and incorporates experimental design and data analysis. More importantly, it introduces