The overall goal of this video is to demonstrate a technique for gaging adult zebra fish. We developed this technique in order to study pathogenic organisms that are transmitted via the oral fecal root. It can be used to deliver a precise amount of solution.
For study to adult zebra fish. The entire process takes four steps. The first is to prepare the gavage apparatus.
The second is to anesthetize the fish with 150 milligrams per liter of buffered MS 2 22. The third step is to gavage the fish with your solution. And the last is recovery of the fish and monitoring for adverse effects.
To make the gavage apparatus cut the 22 gauge implantation tubing to the appropriate length for the fish, attach it to the 22 gauge needle and secure it to the one ml lure lock syringe. When your solution is ready, it can be aspirated into the apparatus. For administration to the zebra fish, a sponge should have a slit cut into it with a scalpel blade or scissors, so that when the fish is placed into the sponge, it is held securely.
The sponge should be pre soaked in system water to keep it moist. A recovery tank composed of system water free from anesthetic should also be prepared to place sufficient once the procedure has been completed. Fasta fish for at least 24 hours before the procedure.
Using a net, transfer the fish to the MS 2 22 anesthetic tank. Once the fish is anesthetized, as demonstrated by lack of response to a tailfin pinch, remove the fish from the anesthetic solution and place it in the sponge so that the head is slightly protruding from the sponge, but the gills are covered. Move the sponge into a vertical position and using the 22 gauge implantation tubing, open the zebra fish's mouth.
Gently insert the tubing until the tip is past the level of the heart. The length varies with the size of the fish, and if there's resistance, gently withdraw, reposition, and try again. There should be no need to force the tube down the zebra fish's intestinal tract.
Once in the proper location, inject the solution and remove the tubing. Place the fish into the recovery tank by releasing it from the sponge. If done correctly, the tubing should slide easily into the zebra fish's intestinal tract.
No solution will be seen exiting the gills or the mouth. No blood will be visualized on the tip of the tubing or coming from the fish's gills. The most common problem is liquid exiting via the mouth or the gills, and this indicates that the tubing was not down far enough into the fish.
This procedure has an overall success rate of 88%When performed properly, no more than five microliters of fluid should be administered as a severely diminishes a success rate of the procedure. When we attempted to administer 10 microliters of solution, the overall success rate dropped to 50%In this video, we demonstrated how to gavage adult zebrafish. This procedure can be used to precisely deliver known quantities of solutions to zebrafish.
The advantages of this technique over previously described techniques as that it uses more flexible material and pregnant females can be gavage more effectively. Thank you for watching and good luck with your work.