15. Zebrafish Development

This is a new chapter that is being prepared for the third edition of the book. The zebrafish, Danio rerio, is a relatively new and important edition to the family of model organisms. With transparent eggs, rapid embryonic development, quick generation time, and ease of maintenance, it is an economical and easy organism to use in the teaching laboratory.

In this chapter, students use the zebrafish to examine possible ill-effects of teratogens that human embryos might be exposed to, including excess vitamin A (a severe threat because of medications such as isotretinoin, a form of vitamin A used for the treatment of severe acne), lithium (a common medication for manic depression), and alcohol (known to cause fetal alcohol syndrome and fetal alcohol effects).

Environmental effects are also examined, such as effects from temperature changes (a recent threat to many species with thermal pollution from energy plants and global climate changes) and endocrine disruptors (widely prevalent pollutants, many acting as estrogens and anti-estrogens).

Tables of developmental stages and a primer on vitamin A and its derivatives are included.

Individual sections include:

Description of normal development
Culturing procedures for adult fish
Behavioral studies
Obtaining and maintaining embryos and larvae
Removing the chorion
Preparation of whole mounts

Background information and procedures for teratogens including:

Increased temperatures
Lithium
Vitamin A
Alcohol
Endocrine disruptors