Gavage Tubes

Gavage, or tube feeding for newly hatched sharks.

Newly hatched sharks can survive off of the absorbed yolk sac for a couple of weeks. If all attempts to feed them have been unsuccessful, intervention may be needed. If the shark begins to show signs of deterioration, such as obvious weight loss and lethargy, gavage (tube) feeding may be the key to getting your shark jump started.

Feedings should be blended into a high-protein food slurry that will fit through the tube. CYCLOPEZEE, shrimp and scallops can usually be blended into a nutritious slurry. Vitamin B12 can be added to the food slurry. This can be an appetite stimulant.

The volume should be 2 to 4 percent of the shark’s weight. So if the shark weighs 15 grams and you want to feed 3 percent: 15 gm (gm = cc/ml) multiplied by 0.03 (3 percent) = 0.45 cc or ml. A teaspoon is 5 ml/cc so this is less than one-eighth of a teaspoon (0.62 ml). A small digital scale or dietary food scale can be purchased at many local stores.

The tube should be small and fairly soft. An angiocatheter used for intravenous fluids works well as does the tubing that is on the butterfly venipuncture collection system. Both can be connected to a syringe to administer the feeding. The tube should be passed to an imaginary line just past the gills of the shark.

Do not force or use pressure to pass the tube. Both gills need to be able to be visualized to make sure the tube has not been passed out of the gills. Once the tube has been passed successfully, slowly infuse the food and remove the tube slowly. The stomach may be palpated or checked visually after feeding.

Click here for more on breeding epaulette sharks.

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Fish · Saltwater Fish