Possible dangers of feeding live Superworms to Arowana

[islandguy11]

I know lots of people have been feeding live SW to their Aros and other fish for many years and apparently never had any issues.

Today though I ran into a very interesting study (2007, by some South Korean scientists) that some might find interesting: Basically it seemed to establish a direct link between live superworm feeding and possible problems/deaths with Arowana: http://kjvr.org/upload/06903762.pdf

The main conclusion if you don't want to follow the link or read the whole thing:
"While the control group fed with yellow mealworm larvae without head part digested the food properly and eliminated the waste products by feces. [with the 2nd control group] We speculated that when the mealworm mandibles with hooks were accumulated, stacked or attached to the mucosal layer of the stomach wall and not eliminated properly together with the waste products, it might cause erosions and ulcerations and eventually cause internal bleeding and death of the fish."

Note though that this might not be true for all fish, as the study mentions it could depend on the anatomical structure of the stomach/digestive system, which differs among species (apparently in another test Oscars passed the SW heads no problem).

 

[Backfromthedead]

I know lots of people have been feeding live SW to their Aros and other fish for many years and apparently never had any issues.

Today though I ran into a very interesting study (2007, by some South Korean scientists) that some might find interesting: Basically it seemed to establish a direct link between live superworm feeding and possible problems/deaths with Arowana: http://kjvr.org/upload/06903762.pdf

The main conclusion if you don't want to follow the link or read the whole thing:
"While the control group fed with yellow mealworm larvae without head part digested the food properly and eliminated the waste products by feces. [with the 2nd control group] We speculated that when the mealworm mandibles with hooks were accumulated, stacked or attached to the mucosal layer of the stomach wall and not eliminated properly together with the waste products, it might cause erosions and ulcerations and eventually cause internal bleeding and death of the fish."

Note though that this might not be true for all fish, as the study mentions it could depend on the anatomical structure of the stomach/digestive system, which differs among species (apparently in another test Oscars passed the SW heads no problem).

Interesting. Could loan support to thd theory that an aquarium fish should not be fed the same diet that a wild fish would.

Could be theres something missing from their diet/nutrient deficiency that inhibits them from producing the necessary enzymes to digest the tougher parts of the worm.

 

[islandguy11]

Interesting. Could loan support to thd theory that an aquarium fish should not be fed the same diet that a wild fish would.

Could be theres something missing from their diet/nutrient deficiency that inhibits them from producing the necessary enzymes to digest the tougher parts of the worm.

Good point to raise, could indeed be true, and on a related point while I kinda doubt Arowana eat superworms in the wild, if they did they likely wouldn't have 10-20 of them to gorge on (which could only increase the chance some SW survived longer during the digestive process, they're actually pretty tough little critters, and will even eat Styrofoam (and survive just fine).

For the record not dishing on peeps who do feed live SW's, again plenty of great fish keepers have been doing it for years and probably had no problem.

I'm on the paranoid side with my fish though, and as I don't feed live anyway would rather gutload, freeze and then cut the heads off right before serving, even if it is more time consuming. I'm thinking of adding SW into my Aros' diet once or twice a week in this manner, just got some a couple of days ago and they're now full of carrots and spirulina powder.

 

[Galantspeedz]

i guess the hook being in the aro stomach is similar to fishing, when some line break and the hook is stuck in the fish stomach....

so they killed and cut up the fish to look at the stomach after the experiment?

 

[Galantspeedz]

Interesting. Could loan support to thd theory that an aquarium fish should not be fed the same diet that a wild fish would.

Could be theres something missing from their diet/nutrient deficiency that inhibits them from producing the necessary enzymes to digest the tougher parts of the worm.

on the same note, is it correct to say that aquarium fish may not need the same water parameters as a wild fish...

 

[islandguy11]

on the same note, is it correct to say that aquarium fish may not need the same water parameters as a wild fish...

Yeah that's also a good question: we can see that many species have successfully adapted to different water parameters in aquariums than they'd have in the wild (e.g. lots of people raise Aros or Discus in higher PH), but then we also see some possible problem fish as well (e.g. Oscars and susceptibility to HITH). I often wonder if my Aros would do better in lower PH water (about 8.0 where I live), but it's just not practical to continuously keep them in lower PH.

 

[boomerk9]

I've seen plenty of Arowanas over here fed with large live centipedes! As you can guess, centipedes have got massive fangs that can easily dig into their guts.
Not sure about the long term effects, but the keepers think the venom brightens the arowana's colours. No idea on whether this is true or myth.

 

[islandguy11]

I've seen plenty of Arowanas over here fed with large live centipedes! As you can guess, centipedes have got massive fangs that can easily dig into their guts.
Not sure about the long term effects, but the keepers think the venom brightens the arowana's colours. No idea on whether this is true or myth.

True that, have seen similar videos on YouTube, it's pretty crazy to watch, though never heard that above the venom, interesting. Maybe with those larger insects the Aros can't swallow them whole and have to tear 'em up, so it's already dead by the time it goes down the gullet, which they don't have to do with SW.

 

[boomerk9]

From my experience with centipedes, the head stays alive for a long time even if the body is crushed or bisected.
Even just a few minutes ago, a keeper posted on a local aro forum looking for live centipedes to feed to his aro.

 

[islandguy11]

From my experience with centipedes, the head stays alive for a long time even if the body is crushed or bisected.
Even just a few minutes ago, a keeper posted on a local aro forum looking for live centipedes to feed to his aro.

Interesting, perhaps it's a numbers thing: maybe 1 centipede ain't no trouble, but if one tried feeding 3 or 4 (or 20 SW) it could be a different story, I'm really not sure. Could also just be a good luck/bad luck thing.

Anyway more power to those who do, personally I just wouldn't take the chance (not cutting off head), imo there are safer (and less messy) foods that will get pretty much the same results.