Gulper catfish trio, ~7"

HarleyK

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Fingers crossed for the gulpers - and everyone else, too, of course!
 
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Mikoa

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Really hope things have been improving! I’ve read through the whole journey and watched lots of your YouTube videos. I’m interested in setting up a gulper tank and really appreciate your hard work and dedication you have for yours. So much good information that I haven’t seen elsewhere. Slightly off topic but I’m curious. Would they do well in a tank with decor (wood, rocks) and sand substrate? I assume all of the bare tank setups are for easier tank maintenance and to better observe the fish. Would they scratch themselves on driftwood and sticks or harm themselves from inhaling sand and leaf litter? Hoping to create a natural display type tank
 
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Umbra

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I know you've mentioned that you're feeding herring - apparently herring, anchovies and related fish contain thiaminase, enough to the point that vitamin B deficiencies have been noted in salmonid populations in the Baltic that feed primarily on herring and alewife consuming populations in the Great Lakes.


This is a pretty good read on thiaminase and predatory fish nutrition. Apparently prawns/tiger shrimp also contain thiaminase, and those are 2 very popular food items for most North American predatory fish keepers.

Is it possible that we see plenty of these predators grow larger/live longer in Asia because of different market fish/invert availability, with Asia having more access to a wider variety of thiaminase free options?
 

thebiggerthebetter

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Really hope things have been improving! I’ve read through the whole journey and watched lots of your YouTube videos. I’m interested in setting up a gulper tank and really appreciate your hard work and dedication you have for yours. So much good information that I haven’t seen elsewhere. Slightly off topic but I’m curious. Would they do well in a tank with decor (wood, rocks) and sand substrate? I assume all of the bare tank setups are for easier tank maintenance and to better observe the fish. Would they scratch themselves on driftwood and sticks or harm themselves from inhaling sand and leaf litter? Hoping to create a natural display type tank
Thank you for your kind words and attention to our humble and rather crude efforts.

Sand substrate is common among gulper keepers. I'd have to reread their fact sheets to recall if in nature they are found over mud or sand, probably not gravel. Not sure about leaf litter but I'd be surprised if this was a problem. Driftwood, roots, etc. is their home. I don't think they'd mind the rocks - ours did ok with concrete blocks even. They like to wedge into anything tight and secure during the day. They also like to be in weeds and some give them a loosely bound yarn ball to hide in (per Sean aka Catfishologist on Planet Catfish).

Yes, for us - minimal maintenance and constant observation are a must, you got it right.

I know you've mentioned that you're feeding herring - apparently herring, anchovies and related fish contain thiaminase, enough to the point that vitamin B deficiencies have been noted in salmonid populations in the Baltic that feed primarily on herring and alewife consuming populations in the Great Lakes.


This is a pretty good read on thiaminase and predatory fish nutrition. Apparently prawns/tiger shrimp also contain thiaminase, and those are 2 very popular food items for most North American predatory fish keepers.

Is it possible that we see plenty of these predators grow larger/live longer in Asia because of different market fish/invert availability, with Asia having more access to a wider variety of thiaminase free options?
Thank you greatly. Yes, I've read Marco Lichtenberger's article and reworked it and incorporated it into a write-up for myself.

However, this is not a complete story and there are controversies. For one instance, Dr. Keller the main vet of the Tennessee Aquarium tells us thiaminase forms in animals after / during death (in all fish it seems he is saying) and its presence and amount depend on the exact manner of death and he recommends to feed live if one really wanted to avoid thiaminase worries. They at the Tennessee Aquarium cannot feed all their predators live so they deposit precise amounts of Thiamine E paste into every frozen/thawed fish they feed to their predators.

That threw me for a loop. I spent so much time digging for any info on which fish species contain thiaminase and which don't... This new info makes it irrelevant but then I'd like to see scientific evidence behind Dr. Keller's words and equally, it is hard for me to discard all the scientific studies on thiaminase content in fish, although I understand science marches on and moreover there is a TON of unscrupulous work done and published in science, which usually can only be picked up by professionals in the same field, not outsiders or even non-aquatic-biologists like us.

As for Asia, if you ask me, I'd guess Asia is not liberal like the West and people there are less avert or scared by the society to feed live feeder fish plus yes, their choices are a bit different, although the high-thiaminase items like carp-likes, shrimp, etc. seem ubiquitous here and there.
 
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jjohnwm

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However, this is not a complete story and there are controversies. For one instance, Dr. Keller the main vet of the Tennessee Aquarium tells us thiaminase forms in animals after / during death (in all fish it seems he is saying) and its presence and amount depend on the exact manner of death and he recommends to feed live if one really wanted to avoid thiaminase worries. They at the Tennessee Aquarium cannot feed all their predators live so they deposit precise amounts of Thiamine E paste into every frozen/thawed fish they feed to their predators.
Now that is interesting! Just to clarify and make certain that I am interpreting this correctly...is the implication here that a fish to be used as a feeder, which is killed and kept frozen for later use, is having thiaminase form within its body after its death? So feeding the same fish live is avoiding the whole thiaminase bogeyman?

Honestly, I think that supplementation with added thiamine is the easiest way around this, rather than feeding live...but it's pretty incredible that we even need find a work-around for something so bizarre.
 
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thebiggerthebetter

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You got my explanation right. Yes, super bizarre to me too but I am open to new knowledge, as I said so long it is backed by trustworthy science, not expert guessing. A highly complex protein that has a complex supramolecular structure (a long molecule, amino-acid polymer folded intricately), an enzyme, an anti-nutrient, which the organism has no use for (and if the organism had this enzyme, the enzyme would likely kill it) but has the precursor, forms inside the organism during/after death and the details of death - time, temp, who knows what else make it happen or not.
 
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Umbra

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You got my explanation right. Yes, super bizarre to me too but I am open to new knowledge, as I said so long it is backed by trustworthy science, not expert guessing. A highly complex protein that has a complex supramolecular structure (a long molecule, amino-acid polymer folded intricately), an enzyme, an anti-nutrient, which the organism has no use for (and if the organism had this enzyme, the enzyme would likely kill it) but has the precursor, forms inside the organism during/after death and the details of death - time, temp, who knows what else make it happen or not.
That wouldn't explain the thiamine deficiency in the Great Lakes population in particular that subsist primarily on alewife versus other piscivorous populations that don't have this issue when consuming a larger variety of fish. Could it be possible that it's present in in different species of fish in varying amounts and, upon death and the rapid breakdown of certain lipids and tissues, it is either produced in greater quantities or perhaps some other molecule breaks down with those tissues and produces another deficiency that leaves the predator more vulnerable to the effects of thiaminase? Garter snake enthusiasts often report of thiamine deficiency in specimens fed live goldfish and rosies but not in those fed livebearers which apparently don't have thiaminase. I almost never hear of anyone feeding goldfish and rosies prekilled so I think it's a pretty safe assumption that the vast majority of cases reported in both the aquarium and herp hobbies involve live feeders.
 
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jjohnwm

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That wouldn't explain the thiamine deficiency in the Great Lakes population in particular that subsist primarily on alewife versus other piscivorous populations that don't have this issue when consuming a larger variety of fish. Could it be possible that it's present in in different species of fish in varying amounts and, upon death and the rapid breakdown of certain lipids and tissues, it is either produced in greater quantities or perhaps some other molecule breaks down with those tissues and produces another deficiency that leaves the predator more vulnerable to the effects of thiaminase? Garter snake enthusiasts often report of thiamine deficiency in specimens fed live goldfish and rosies but not in those fed livebearers which apparently don't have thiaminase. I almost never hear of anyone feeding goldfish and rosies prekilled so I think it's a pretty safe assumption that the vast majority of cases reported in both the aquarium and herp hobbies involve live feeders.
I don't think that is necessarily a discrepancy. Consider the possibility that thiaminase is found in some types of fish more than others, but that upon or after death all fish begin to see elevated levels of it; I have no idea how this would work but it seems possible.

Remember also that the populations of salmonids in the Great Lakes...with the exception of Lake Trout and the odd Atlantic Salmon...are all introduced Pacific marine species, which in nature would never be adapted to feed upon Gizzard or Threadfin Shad. Surely it is reasonable that predators which evolve in a habitat where most prey items contain thiaminase would be resistant to its effects, whereas those that are forced by circumstance to feed upon high-thiaminase prey to which they are not adapted by evolution might suffer for it.

I'm not saying that I buy into any of this, but I think the possibilities must be explored.
 

thebiggerthebetter

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U: That wouldn't explain the thiamine deficiency in the Great Lakes population in particular that subsist primarily on alewife versus other piscivorous populations that don't have this issue when consuming a larger variety of fish.
***Right on. I too have more questions than answers. It does sound like some fish must have it when they are alive. In all fairness, Dr. Keller didn't deny this, he just didn't address it in my secondhand interaction with him (through someone else). Sean aka Catfishologist on PCF said he would summarize his learning from Dr. Keller, to who Sean took his sick gulper for analysis and cure. I am waiting for this.

U: Could it be possible that it's present in in different species of fish in varying amounts
***It follows that it must be present in living fish. But I read scientists don't even know what the function of this antinutrient would be for the fish in which thiaminase occurs, perhaps for the lack of searching the answer or for the so-far insurmountable complexity. Everything that exists inside an organism only does so to serve a concrete purpose. It is ONLY believed that thiaminase in some ferns (plants) serves to defend against insects, and even this seems a general logical assumption and not a result of concrete study and proof. The death of Australian explorers is ascribed to eating thiaminase-laden ferns.

U: and, upon death and the rapid breakdown of certain lipids and tissues, it is either produced in greater quantities or perhaps some other molecule breaks down with those tissues and produces another deficiency that leaves the predator more vulnerable to the effects of thiaminase?
***That would be overly complicated. In such a way it might be possible to explain everything but prove nothing. Occam's razor is good to apply.

U: Garter snake enthusiasts often report of thiamine deficiency in specimens fed live goldfish and rosies but not in those fed livebearers which apparently don't have thiaminase.
***It seems to have only been guessed that livebearers don't have thiaminase or not much of it. Again, too much guessing makes everything uncertain.

U: I almost never hear of anyone feeding goldfish and rosies prekilled so I think it's a pretty safe assumption that the vast majority of cases reported in both the aquarium and herp hobbies involve live feeders.
***Agreed. Cyprinids are known bad offenders afa thiaminase goes, live or dead.

JJ: I don't think that is necessarily a discrepancy. Consider the possibility that thiaminase is found in some types of fish more than others, but that upon or after death all fish begin to see elevated levels of it; I have no idea how this would work but it seems possible.
***Well, yes, the salmonids in Baltic sea and in Great Lakes do kill their prey after all. I'd agree with Umbra - things don't add up yet.

JJ: Remember also that the populations of salmonids in the Great Lakes...with the exception of Lake Trout and the odd Atlantic Salmon...are all introduced Pacific marine species, which in nature would never be adapted to feed upon Gizzard or Threadfin Shad. Surely it is reasonable that predators which evolve in a habitat where most prey items contain thiaminase would be resistant to its effects, whereas those that are forced by circumstance to feed upon high-thiaminase prey to which they are not adapted by evolution might suffer for it.
***Perhaps logical, yes. But IIRC the Baltic sea salmonids and their herring prey were native. Also, people changed so much in the world's waters everywhere, changing the food chains, the diversity of prey that used to sustain the predators, introducing exotics, wiping out whole classes of prey, etc.

JJ: I'm not saying that I buy into any of this, but I think the possibilities must be explored.
***To me, the only clarity possible may or may not come from hearing out the professionals, especially those with opposing views.
 
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thebiggerthebetter

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Gulpers showed a bad effect from formalin-MG treatment after 1-2 days, hanged on for 10 days, got better, then worse, and died. They are the two that had been sick from the B1 deficiency and received the B1 injection 2 months ago, behaved normal since then but have not fed. Sadly, we'll never know if they would have eventually regained their appetite and vitality after the B1 shots but they certainly regained normal behavior after the shots.

I forgot the full dose is too much for them.

The third one that had NOT been sick with the B1 deficiency and fed adequately still holds on, seems to be getting better slowly but each day.

As for these two - we had them 14 months, they grew from 6" to 9". I believe they are the last 2 of the 7 we bought from Predatory Fins in Nov 2021.

 
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