Zebrafish as a Model Organism

Zebra Fish, Zebra Danios, or Danio rerio, are small fish that originate from streams in India. They have recently come to prevalence in the scientific community for research, as they have many attributes that make them a great model organism. In the CHAOS lab, zebrafish is the most commonly used animal for experimentation, and are mainly used in Optical Mapping and Microelectrode.

Zebrafish As a Model Organism

Zebrafish have mant traits that make them optimal as model organisms, including: As a general model organism

• High fertility: Zebrafish can have lots of offspring in one brood
• Short generation time - reaches sexual maturity in 1.5 months, full adulthood in 3
• Smaller space requirement that other vertebrate models like mice - make them a much more financially feasible option, in addition to being very inexpensive to purchase/ grow in general
• It is easy to produce large numbers of zebrafish in a laboratory setting
• Almost fully sequenced genome that is highly conserved with humans

For studying cardiovascular disorders:

• Heart function can be assessed visually - can visually monitor dynamic cellular events
• There are a huge variety of mutants that resemble human disorders
• Heart can regenerate quickly after injury
• Hearts are small enough that they can be essentially simplified to single cells for certain purposes, particularly Microelectrode,

Prepping For experiment

When preparing to remove the zebrafish's heart for experimentation, it is important to ensure that the procedure is painless for the fish. To ensure this, fill a 250mL beaker with ice from the machine in the Southwest corner of Howey's 2nd floor. Remove a zebrafish from the tank, and submerge the fish in the ice for 2 minutes. The cold will shut down the fish's main body functions, rendering it essentially brain dead, but the heart will continue to beat, which is necessary for experimentation.

Removing the Heart

Remove the Zebrafish from the ice bath and place it upside - down on the dissection tray. Take one pin and put it through the fish's tail, and put another through it's head, keeping it in place for heart removal. Next, use small scissors to cut a line all the way down the fish's center, as well as one perpendicular to the first line, running between the gills. With these cuts, it is then easy to pull back the skin on the belly of the fish and pin it into the foam of the dissection table, keeping it out of the way. Lastly, use the tweezers to search inside the zebrafish for the heart. You'll have to do some digging. Or just whine and get Conner to do it for you.

Care for Zebrafish

Feed them and clean the tanks.