Live Feeder and Thiaminase Discussion

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SourAngelfish

Dovii
MFK Member
Jan 22, 2021
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Has anyone looked to how/if thiaminase causes harm to certain species of fish? It is clear that marine fish and cichlids fed live cyprinid diets such as minnows and goldfish often have health issues down the road. This makes sense as there are little to no thiaminase carrying prey fish in their environments/diets.

Now take a look at certain North American, European, and Asian fish, barbs/minnows/other carps tend to take place in most aquatic food chains with piscivorous fish. Obviously there are many non-fish/non-thiaminase carrying options in these locations, but many fish such as clown knives, sunfish, gar, and others are in habitats with profuse amounts of thiaminase carrying fish. Are thiaminase carrying fish unaffected by prey items that contain it? Obviously it’s never healthy to feed a diet of a single fish but would one be doing harm to their fish feeding it quarantined goldfish if it happened to contain carp-like fish in its natural diet?

would love to see people’s input, I know many crustaceans carry this potentially harmful enzyme as well.
 
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Has anyone looked to how/if thiaminase causes harm to certain species of fish? It is clear that marine fish and cichlids fed live cyprinid diets such as minnows and goldfish often have health issues down the road. This makes sense as there are little to no thiaminase carrying prey fish in their environments/diets.

Now take a look at certain North American, European, and Asian fish, barbs/minnows/other carps tend to take place in most aquatic food chains with piscivorous fish. Obviously there are many non-fish/non-thiaminase carrying options in these locations, but many fish such as clown knives, sunfish, gar, and others are in habitats with profuse amounts of thiaminase carrying fish. Are thiaminase carrying fish unaffected by prey items that contain it? Obviously it’s never healthy to feed a diet of a single fish but would one be doing harm to their fish feeding it quarantined goldfish if it happened to contain carp-like fish in its natural diet?

would love to see people’s input, I know many crustaceans carry this potentially harmful enzyme as well.

Great question would like to know that myself.
 
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duanes duanes . Quite interested myself. Goldfish feeders are prevalent in my country, but I know they contain high amounts of thiaminase so I don’t feed them
 
I’ve always wondered if there’s some secret to goldfish. I’ve seen people on Facebook with perfectly healthy Asian aros with no drop eye/gars and they dump goldfish in their tanks for them to snack on. I know Facebook is hardly ever the standard nor is it reliable but I can’t help but be intrigued seeing someone feeding foods regarded by many as bad and still have very healthy fish
 
I’ve always wondered if there’s some secret to goldfish. I’ve seen people on Facebook with perfectly healthy Asian aros with no drop eye/gars and they dump goldfish in their tanks for them to snack on. I know Facebook is hardly ever the standard nor is it reliable but I can’t help but be intrigued seeing someone feeding foods regarded by many as bad and still have very healthy fish
I’d always feed my fish goldfish feeders in the past, with no side effects. But i still heeded the advice here and stopped feeding goldfish and switched to tiger barbs instead.
 
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I’d always feed my fish goldfish feeders in the past, with no side effects. But i still heeded the advice here and stopped feeding goldfish and switched to tiger barbs instead.
Interesting… funny thing is, being barbs, tiger barbs also carry the same enzyme of thiaminase that makes goldfish supposed poor feeders, they could be argued as just as bad theoretically.
 
Interesting… funny thing is, being barbs, tiger barbs also carry the same enzyme of thiaminase that makes goldfish supposed poor feeders, they could be argued as just as bad theoretically.
Wait really ?? oops… nothing wrong seems to be happening to my fish though.. so I’ve been buying feeder fish which are more expensive but just as unhealthy? Lol
 
Although we recognize Thiaminase is a problem, I find the introduction of parasites a much more immediate concern using feeders.
Most commercial feeder fish are (if not wild caught, such as minnows) raised under substandard and crowded conditions, often fed and gut loaded with Krapp, in order to save money, so they can be sold as cheaply as possible.
And under those conditions disease and parasites can run rampant. And all it takes is one to wipe out an entire tank.
With wild caught minnows and other cyprinids the introduction of parasites is also a concern.
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When adding wild caught tetras(above) to my tank, I went over each one with a tweezers needing to pull off at least 1 Lernae on each one.
And where I live there are no LFSs, or even Pet Stores available unless I take a ferry and a cab to the mainland quite a ways away, so I am forced to use trimmings from marine (salt water fish meat I eat) from local fisherman to occasionally feed my tank, because there is less chance of them carrying a parasite that is transferable to freshwater fish (although it is still a gamble, so I inspect the meat for any visible nematodes or the like.
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I would much prefer to use a commercial pellet when available, as I consider them much healthier.
 
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bump out of my continuing curiosity

thiamniase in invasive forage fish (alewives?) has been a huge hurdle in rsstablishing even hatchery supported Atlantic salmon runs on the east coast and the problem has had a devastating effect on trout salmon and steelhead stocks in Lake Huron. It has a significant effect on egg production and fry viability in those species.

I use gambusia and baby cichlids as feeders.
 
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