What are the advantages and disadvantages of using zebrafish in labs?

Advantages: • They can be kept at fairly high densities in a small tank • They lay large numbers of easily collectible eggs • The eggs are clear and easily observed and manipulated • They develop fast • Their generation time (egg to adult) is short • They are vertebrates • Expense. Fish are cheaper to maintain than mice, but more expensive than flies--another powerful model organism. Disadvantages: • They require water systems to maintain them • They are not mammals and are not as closely related to humans as a mouse is. • Reverse genetics has not been worked out for zebrafish as it has in the mouse. • No way of targeting mutations. In mice, for example, you can "knock out" a gene if you have the sequence, and ask why it is needed. In zebrafish, we create random mutations and look for specific defects. Then we have to go and find what sequence is responsible for the defect. • Fly (Drosophila) genetics is much more powerful than fish genetics, because many genetic tools and tricks ...  more