Adult Zebrafish Intestine Dissection: A Technique to Analyze Compound Absorption

- Place a euthanized fish on filter paper and pat it dry. Keep the fish on a dissecting mat. Pin the eye socket at the anterior end and the tail at the posterior end. Cut the skin and underlying muscle along the belly from the anal fin to the operculum, the hard covering over the gills.

Remove the operculum and pectoral fin. Cut the skin and underlying muscle from the gills posteriorly along the side of the fish to the upper anal fin. Now, open the incision with the help of a fine tweezer. Remove the gastrointestinal system from the body and place it on the filter paper.

Separate the intestine from other internal organs. The intestine is folded into three sections, the rostral intestinal bulb, mid intestine, and caudal intestine. Hold the anterior and posterior part of the intestine with the tweezer and gently stretch it out. Roll the intestine on the filter paper to remove all adhesive tissues. In the following protocol, we will isolate the intestine from an adult zebrafish to analyze the uptake of immuno stimulants.

- After euthanizing the fish according to the text protocol, place the fish on a piece of filter paper. Using sharp dissection scissors, make a semicircular incision from the anus to the operculum and open the incision with fine tweezers. Then cut both ends of the intestine, take out all of the internal organs, and place them on the filter paper. Next, separate the intestine from the internal organs and stretch it out, taking care to obtain all of the intestine. Finally, use tweezers to roll the intestine on the filter paper to detach the adhesive tissue.