I tried force feeding a Regal Angel that was on hunger strike for 7 weeks and it didn't end too well.
If you have MS-222, you could force-feed these pretty easily - you might also be able to use clove oil. However, I think the root cause of the anorexia needs to be fixed, and handling them is just going to create more wear and tear. If you decide otherwise, here is an excerpt from my upcoming disease book:
The tube-feeding process can be employed to give the fish food energy during the time it is anorexic. In some cases, this gives the aquarist enough time to determine a permanent solution. This process uses simple equipment—a syringe and a flexible plastic tube. Feline urinary catheters or avian tracheal tubes can be used for small fishes. Larger fishes can be fed using standard airline tubing attached to a large syringe. A Luer-lock syringe will hold the feeding tube more securely to the syringe body. Placing the tube is easier if you first bevel the end of it. The tube should have marks on it at regular intervals so you can more easily judge the depth of insertion.
The basic food recipe is to create a liquid that will easily pass through the feeding syringe and tube but is thick enough to carry a high amount of calories to the animal’s digestive tract with the least amount of water. It is best to prepare this slurry in a blender, using components of the fish’s normal diet.
The amount of food administered at one feeding is generally 2 to 4% of the animal’s body weight, just enough food to cause a slight distension of the animal’s belly. In most cases, the use of an anesthetic, such as MS-222, is required to sedate the fish so the tube can be inserted. Holding the fish on its back, gently insert the tube into its mouth and try to locate the esophagus. If you are too far to one side or the other, the tube will miss and emerge from under one of the gill covers. Once in place, gentle pressure on the syringe plunger will move the liquid food into the fish’s stomach. Once fed, the tube is gently withdrawn and the fish is moved to a recovery tank.
Spontaneous regurgitation is the most commonly seen problem, though there are also reports of people accidentally rupturing the fish’s digestive tract. Like any medical procedure, there are subtle techniques for this process that need to be learned through practice—so please do not expect to read this basic introduction and suddenly be proficient at tube-feeding fish.
Force-feeding is a technique that can be employed on larger carnivorous fishes. A sedated fish is held on its back while its mouth is opened, and a food item of appropriate size for the animal is then placed in the back of the animal’s throat. A finger or semi-rigid tube is then used to gently push the food item into the stomach. In some species, such as anglerfish and eels, there are back-curved vomerine teeth in the throat that will actually grasp the food item and keep the fish from voluntarily regurgitating it.
Be cautious in directly handling a fish during either of these two techniques, as some have very sharp teeth and, of course, some fish have venomous spines.
The following case histories will help describe some common scenarios where tube feeding has been used, showing cases that did and did not have a successful outcome.
Pinnatus batfish: Perhaps the first time this species of fish had ever been tube fed, this case was unique enough to be written up in an aquarium magazine (Hemdal 1985, 1997). In this instance, the animal eventually perished due to secondary infection apparently caused by handling during the feeding procedure. Still, the animal was kept alive long enough to actually show some growth derived solely on the food energy it was gaining by being tube fed, and it did eventually begin to feed a bit on its own.
Pacu,
Colossoma macropomum: One specimen was reported to have stopped feeding for approximately four months at a major public aquarium. There was no discernible cause for this. After 12 days of daily tube-feeding, it began to feed on its own again and did not show any further signs of anorexia. Likely, an unidentified environmental factor caused this fish to suddenly stop feeding. In a similar case, a Moorish idol,
Zanclus canescens had adapted well to captivity when it suddenly stopped eating. A bulge in its posterior abdomen indicated that perhaps the fish had a blockage in its digestive tract. Within a week, the swelling disappeared and the fish resumed normal feeding.
Butterfly ray: As an aquarist for a major public aquarium, I had ordered one of these fish from a collector. Upon its arrival, my curator commented, “Too bad you didn’t ask me before ordering this fish – they always starve to death in captivity”. Wanting to prove that I didn’t make a mistake in ordering the fish, I began a three times per week tube feeding regimen for it. The animal actually began to grow as I kept up the procedure for two months. Ultimately, I became too comfortable with the procedure, and I was careless one time and inadvertently ruptured the animal’s stomach by inserting the feeding tube too far and it subsequently died of an infection.
Walking batfish: A group of these fish arrived from a collector and soon began feeding well on live mysids and brine shrimp. Previous experience with these fish told us that they are often severely infected with internal worm parasites. Our most common means of feeding anti-helminthics (de-wormers) was via medication added to gelatin food. As these fish wouldn’t eat that food, they were force fed a liquid food with an appropriate amount of Fenbendazole (Panacur) added. The next day, all the fish were seen expelling many dead worms from their vents and went on to be healthy aquarium inhabitants.
Garden eels: Apparently, due frequently being collected with chemicals, these fish often refuse to feed in captivity. In some cases, tube feeding them for a few weeks will keep them alive long enough that they will begin feeding on their own. The primary problem with tube feeding these fish is that you must use MS-222 to anesthetize the fish each in order to get it out of its sand burrow. Eels that are too weak to create a burrow generally do not survive no matter what you do for them.
Talma butterflyfish: This case was interesting in that the animal did not feed when it was first acquired, but soon began feeding on its own once it had been tube fed a couple of times. It then lived problem free for almost a year, and then suddenly for no apparent reason, stopped feeding. It was tube fed three times a week for two months, but never began feeding on its own again and was eventually euthanized for humane reasons.
Weedy scorpionfish: This animal had refused all food for 6 weeks after its arrival. After tube feeding it once it began feeding on live fish the next day and was soon converted over to sliced seafoods. This case was special in that the species is venomous so great care had to be taken during the procedure so that nobody got stung. For safety of the aquarist, the use of MS-222 anesthetic would be mandatory in cases like this.
Weedy seadragon: A very rare and valuable fish, this animal had been in captivity for two years when it suddenly stopped feeding on live mysid shrimp (the only food it would accept). It refused food for a month while it was treated with various anti-protozoan medications. It began feeding on its own for two days, and then stopped feeding again. This time it was suspected that the animal had developed a secondary bacterial infection. It was tube fed using a very tiny catheter during the four weeks it was given antibiotic injections. No anesthetic was needed, but inserting the tube through the animal’s long narrow snout proved very difficult. About a week after the last injection, the seadragon began feeding on its own and did well after that.
Appetite stimulants are frequently suggested to help get a fish feeding normally. Vitamin B12 and garlic extract are two commonly touted remedies. These rarely, if ever work as hoped. If the fish is being offered an inappropriate food (brine shrimp to a coral-feeding butterflyfish for example) stimulating the fish’s appetite isn’t going to help. Likewise, if a fish is anorexic due to an environmental issue or disease process, those issues must be remedied first.
Jay
