Simple gist: Thiaminase destroys thiamin / vitamin B1. It occurs in some foods & can accumulate to some degree in predator. B1 intake is proper for fish on all-in-one commercial dry foods or a correct variety. If you use (or your fish eats)
only fresh or frozen foods, even if fortified with supplement like VitaChem, the foods must be biased towards thiaminase-free species, because some fish species contain thiaminase & some don’t, regardless frozen or fresh, f/w or s/w. If thiaminase-rich foods are used not occasionally but most or all the time, a thiamin deficiency, sickness & death will eventually ensue. Thiamin deficiency can be treated with massive doses of thiamin. Don’t feed fish with thiaminase to your fish. There are alternatives.
Thiamine, also known as thiamin & vitamin B1, is a vitamin, an essential micronutrient, that cannot be made in the body. It is found in food & commercially synthesized to be a dietary supplement or medication. It participates in conversion of carbohydrates into glucose. It is particularly important for the correct functioning of the nervous system. Thiamine & some of its phosphorylated forms are required for metabolism including that of glucose, amino acids, & lipids.
And all living things need thiamin for their bodies to function properly but while plants, fungi & bacteria can synthesize their own thiamin, animals must get it from their diet. Animals whose diet is deficient in thiamin suffer from
neuropathic &
cardiovascular disorders. Thiamine is found in a wide variety of foods. Lentils, peas, whole grains, pork, & nuts are rich sources. Grain processing removes much of the thiamine content, so in many countries cereals & flours are enriched with thiamine. Supplements & medications are available to treat & prevent thiamine deficiency & ensuing disorders. They are typically taken by mouth but may also be given by intravenous or intramuscular injection.
Thiamine is a cation soluble in water, methanol & glycerol, insoluble in less polar organic solvents. It is usually supplied as a chloride salt. In the body, thiamine can form derivatives; the best-characterized form is thiamine pyrophosphate (TPP), also called thiamine diphosphate, a coenzyme in the catabolism of sugars & amino acids.
Thiamine is stable at acidic pH, but it is unstable in alkaline solutions & from exposure to heat. It reacts strongly in Maillard-type reactions (amino acid + sugar = taste). Oxidation yields the tricyclic fluorescent derivative thiochrome, which can be used to determine the amount of the vitamin.
Because it’s a water-soluble vitamin,
B1 in fish is easily lost to the environment & cannot be stored in the body, but a daily input is essential to good health. Fat-soluble vitamins can be stored, so a daily supply isn’t important provided the animal can occasionally top up its fat-soluble vitamin stores.
Dosage For US food & dietary supplement labeling purposes, the amount in a serving is expressed as a percent of Daily Value. Since 2016, the Daily Value has been 1.2 mg, in line with the RDA. The National Academy of Medicine & the EFSA set no upper intake levels for thiamine, as there is no human data for adverse effects from high doses.
Safety Thiamine is generally well tolerated & non-toxic when administered orally. There are rare reports of adverse side effects when thiamine is given intravenously, including allergic reactions, nausea, lethargy, & impaired coordination.
Synthetic analogues Benfotiamine, fursultiamine, sulbutiamine & others listed as vitamin B1 analogues are synthetic derivatives of thiamine. Most were developed in Japan in the 1950s & 1960s as forms that were intended to improve absorption compared to thiamine.
Thiamine deficiency causes beriberi, Wernicke–Korsakoff syndrome, optic neuropathy, Leigh's disease, African seasonal ataxia (loss of full control of bodily movements).
Human Symptoms include malaise (non-specific, feeling of uneasiness, discomfort, anxiety, fear, depression), weight loss, irritability & confusion. Also causes central pontine myelinolysis - a neurological condition involving severe damage to the myelin sheath of nerve cells in the pons (an area of the brainstem). It is predominately iatrogenic (treatment-induced), & is characterized by acute paralysis, dysphagia (difficulty swallowing), dysarthria (difficulty speaking), & other neurological symptoms.
Fish Symptoms - B1 deficiency / excess Thiaminase relate to poor growth, loss of appetite, abdominal swelling & hemorrhage, loss of equilibrium, convulsions, muscle atrophy & a weak immune system (see Examples below).
Thiaminase is an
antinutrient, an enzyme (biological catalyst made of protein), which breaks down thiamine into two molecular parts. Thiaminase is of greatest concern to people feeding animals a fish-heavy diet. Occasional feedings should be irrelevant, but frequent feeding could in theory keep enough thiaminase in the gut to degrade thiamine. In other words, regular intake of substantial amounts of food containing thiaminase could introduce enough thiaminase into the gut to break down the thiamine in food & render an animal thiamine-deficient. There are 2 types or more, some of which can be produced by bacteria, fungi, plants & maybe animals. |||
Ref 8. Two thiamin-cleaving enzymes have been identified, thiaminase I Thiamine pyridinylase & thiaminase II Aminopyrimidine aminohydrolase.
Thiaminase I is found in shellfish, clams (but not oysters), some f/w fish viscera, crustacea, & certain ferns, but very few higher plants. Also, certain species of Bacillus & Clostridium, which are components of the human & animal intestinal flora, have been found to produce this enzyme. The enzyme catalyzes an exchange reaction, in which the thiazol moiety of the molecule is displaced by another N-containing base or a SH-compound. T. I uses nucleophiles such as quinoline, aniline, & pyridine but not water. T. I may also be produced by the rumen microflora of ruminants (sheep, goats, cattle) or by plants, and, in the presence of suitable cosubstrates, e.g., niacin, or pyridoxine, & certain antihelmintics, seems to be responsible for the ruminant CNS disorder, polioencephalomalacia.
Thiaminase II is of bacterial origin (mostly Bacillus, Candida, & Oospora) & breaks down the free vitamin, but not the thiamin pyrophosphate, into pyrimidin & thiazol components. Contrary to T. I, T. II uses only water as the nucleophile & accepts only thiamin as the substrate
. More prevalent are thermostable thiamin-inactivating factors of plant origin, e.g., polyphenolic substances such as flavonoids & catechol derivatives in fermented tea, ferns, sweet potatoes, & betel nuts, &, in small quantities, in other leaves, fruits, & roots. These can decompose the thiazol component of the vitamin, accelerate the oxidation to the disulfide form, or form unabsorbable adducts with thiamin. Rats fed on food high in polyphenolics have been shown to develop disorder due to a marked drop in levels of cerebral thiamin & thiamin-dependent enzymes. Likewise in man, high tea consumption leads to a deficient thiamin status, but ascorbic acid, if present, completely inhibits the thiamin-inactivating processes.
Thiaminase Sources include:
- about half of tested f/w & half of s/w fish contain it, particularly in the head & viscera
- shellfish, many different invertebrates have also been found to contain Thiaminase, including mussels, clams & shrimps/prawns, e.g., those in the genus Penaeus, sometimes in even higher concentrations than those found in fish
- bracken (genus of large coarse ferns), nardoo (genus of 65 aquatic ferns), horsetail (Equisetum fern), & other plants
- a few strains of bacteria e.g. Paenibacillus thiaminolyticus (Bacillus thiaminolyticus), Bacillus aneurinolyticus, B. subtilis
- fungi
- an African silk worm Anaphe venata.
Its physiological role for fish, bacterial cell or insect is not known. However, in ferns it is thought to offer protection from insects.
Examples:
- well known from several commercially important fish groups & can be confirmed by biochemical tests
- losses in yellowtail (amberjack) fed raw anchovy as a sole feed for a certain period
- same in in sea bream
- same in rainbow trout
- flatfish (flounder etc) fed exclusively with Thiaminase-rich clams suffer & die from paralysis & related physical shocks
- eels show a trunk-winding syndrome & hemorrhages along the base of the fins (reported for morays too)
- salmonids &
a variety of ornamental fish species show nervous disorders, poor appetite, poor growth & jumpiness
- skin congestion & hemorrhage have been reported from carp & other cyprinids
- discovered in 1941 as the cause of highly mortal ataxic neuropathy in fur-producing foxes eating raw entrails of river fish like carp
- known cause of cerebrocortical necrosis of cattle & polioencephalomalasia of sheep eating thiaminase containing plants
- the larvae of a wild silkworm Anaphe venata are being consumed in a rain forest district of Nigeria as a supplemental protein nutrition, & the heat-resistant thiaminase in it is causing an acute seasonal cerebellar ataxia named African seasonal ataxia
- fish-eating
waterfowl: weight loss, 'star gazing' (opisthotonos, spasm of the muscles causing backward arching of the head, neck, & spine), anorexia, digestive upsets, ataxia, convulsions. Extreme anorexia, polyneuritis, weight loss & death in
chickens, with sudden onset in chicks, more gradual onset in adults.
- ref. 7: A Red-sided Garter
snake (Thamnophis sirtalis parietalis) was fed frozen bait minnows 2 times a week. A few months it repeatedly went into convulsions, thrashing around the cage, gaping, & looking like it was having seizures. Around 1980, the Canadian Museum of Nature lost 60+ garter snakes & water snakes due to thiamin deficiency.
It is widely rumored that frozen fish is prone to contain more thiaminase than fish that has not been frozen. But why would this be so? Is it because thiaminase-containing fish are amongst species offered frozen, or because thiaminase is formed when some fish are frozen &/or thawed? It makes no sense to me that something as complex as an enzyme would accidentally be made when fish is frozen & thawed. However, if thiaminase were contained in the fishes’ cells, when those cells ruptured this might release thiaminase, making it easier to measure. I would expect digestion to rupture all the cells in a prey item, anyway.
However, in Practical Encyclopedia of Keeping & Breeding Tortoises & Freshwater Turtles, on Page 90 A. C. Highfield states that the enzyme thiaminase forms in fish after death. I have no idea where he got such info & can neither prove nor disprove it. He also states that aquatic turtles with a diet including fish should always be provided a concurrent vitamin B1 supplement.
Options to combat thiaminase deficiencies include:
- Oral supplementation of thiamine.
- Avoiding fish known to contain thiaminase – no rosy reds or goldfish! & who knows if guppies or platys contain it or not?
- Don’t feed thiaminase-containing fish over once per week on an ongoing basis; feed food containing thiamine (like pellets) after your pet has had no fish for a few days, which should help ensure the thiamine is not destroyed & is absorbed.
-
Heat: Thiaminases are denatured & deactivated by heat. Ref. 7: heat the fish to 80°C (175°F) for a few minutes (me: but beware that it makes fish a mush). Ref. 9: B1 is a delicate vitamin destroyed by heat, e.g., the meat used for dog food kibble is cooked several times at >230°F, & AAFCO (2008) states “processing may destroy up to 90% of B1”. That is why kibble companies add the synthetic B1 back.
Nutrient Requirements of Mink & Foxes, Second Revised Edition, 1982, Pages 64 & 65, provides tables of fish reported to contain & not to contain thiaminase. The lists are far from complete, but most of the usually marketed & so far examined species are enlisted. Although primarily based on coldwater food fish & invertebrates, Thiaminase content information exists for several widely marketed tropical species & are included.
Freshwater fish containing Thiaminase
There are really only three groups of foods dangerously rich in thiaminase: mussels (popular, cheap & available), crustaceans (the widely used prawns & shrimps), & cyprinids (carp, goldfish, minnows, danios, etc.). Among the human food fish families, species containing T. include carps, minnows, herrings, anchovies, goatfishes & snappers.
Family Cyprinidae (Minnows or carps):
All Cyprinidae - carp Cyprinus carpio, rudd, roach, goldfish Carassius auratus, tench, minnow etc
Common bream (Abramis brama) (not the U.S. fish)
Central stoneroller (Campostoma anomalum or Campostoma anomalum pullum)
Emerald shiner (Notropis atherinoides)
Spottail shiner (Notropis hudsonius)
Buckeye Shiner – Notropis atherinoides
Rosy red, Fathead minnow (Pimephales promelas)
Olive barb (Puntius sarana)
Family Salmonidae (Salmonids):
Lake whitefish (Coregonus clupeaformis)
Round whitefish (Prosopium cylindraceum or c. quadriaterale)
Family Catostomidae (Suckers):
Common white sucker (Catostomus commersonii)
Bigmouth buffalo, Buffalofish (Ictiobus cyprinellus)
Family Ictaluridae (North American freshwater catfishes):
Brown bullhead catfish (Ameiurus nebulosus)
Bullhead catfish – Ameiurus spp
Channel catfish (Ictalurus punctatus)
Other families:
Bowfin (Amia calva) - family Amiidae (Bowfins)
Burbot (Lota lota) - family Lotidae (Hakes & burbots)
Burbot (Lota Lota maculosa)
White bass (Morone chrysops) - family Moronidae (Temperate basses)
Smelt Osmerus spp, Rainbow smelt (f/w smelt Osmerus mordax) - family Osmeridae (Smelts)
Smelt per
https://www.monsterfishkeepers.com/...ase-what-you-need-to-know.167891/post-5442632 (the link in the post is lost though)
Loach, Weatherfish (Misgurnus sp.) - family Cobitidae (Loaches)
Garfish (Garpike)
Brackish fish containing Thiaminase
Family Clupeidae (Herrings):
Alewife (Alosa pseudoharengus), lives in f/w too
American Gizzard Shad (Dorosoma cepedianum)
Other families:
Sea lamprey (Petromyzon marinus) - family Petromyzontidae (Lampreys)
Fourhorn Sculpin (Triglopsis quadricornis or q. thompsonii) - family Cottidae (Sculpins)
Salmon (sp. indet., processed & salted, probably Oncorhynchus sp.) - family Salmonidae (Salmonids)
Marine fish containing Thiaminase
Family Engraulidae (Anchovies):
Broad-striped anchovy (Anchoa hepsetus)
Californian anchovy (Engraulis mordax)
Goldspotted grenadier anchovy (Coilia dussumieri)
Family Clupeidae (Herrings):
Atlantic herring (Clupea harrengus)
Baltic herring Clupea harrengus var. membranus
Atlantic menhaden aka ogy, Shad, Bunker, Mossbunker, Fatback, Razor Belly, Alewife, LY (Brevoortia tyrannus)
Gulf or large-scale menhaden (Brevoortia patronus)
Razor belly or scaled sardine (Harengula jaguana = pilchard, white bait, horse minnow) (H. pensacolae)
Sauger (Harengula jaguana) (Stizostedion c. canadense)
Family Scombridae (Mackerels, tunas, bonitos):
Chub mackerel Pacific mackerel Northern mackerel (Scomber japonicus)
Skipjack tuna (Katsuwonus pelamis)
Yellowfin tuna (Neothunnus macropterus)
Family Lutjanidae (Snappers):
Green jobfish (Aprion virescens)
Ruby snapper (Etelis carbunculus)
Crimson jobfish (Pristipomoides filamentosus)
Family Carangidae (Jacks):
Giant trevally (Caranx ignobilis)
Doublespotted queenfish (Scomberoides lysan)
Bigeye scad (Selar crumenophthalmus)
Family Mullidae (Goatfishes):
Red Sea goatfish (Mulloidichthys auriflamma)
Yellowstripe goatfish (Mulloidichthys samoensis)
Manybar goatfish (Parupeneus multifasciatus)
Other families:
American butterfish (Peprilus triacanthus) - family Stromateidae (Butterfishes)
Southern ocellated moray (Gymnothorax ocellatus) - family Muraenidae (Moray eels)
Bonefish (Albula vulpes) - family Albulidae (Bonefishes)
Milkfish (Chanos chanos) - family Chanidae (Milkfish)
Common dolphinfish (Coryphaena hippurus) - family Coryphaenidae (Dolphinfishes)
Hawaiian flagtail (Kuhlia sandvicensis) - family Kuhliidae (Aholeholes)
Black cod (sp. indet.) - family Moridae (Morid cods)
Flathead grey mullet aka striped (US, American Fisheries Society name), black, bully, common, grey, sea mullet, & just mullet (Mugil cephalus) - family Mugilidae (Mullets) Ref. 2
Sixfinger threadfin (Polydactylus sexfilis) - family Polynemidae (Threadfins)
Regal parrot (Scarus dubius) - family Scaridae (Parrotfishes)
Swordfish (Xiphias gladius) - family Xiphiidae (Swordfish)
Dogfish, Spurdog sharks Squalus spp
Whiting Gadus merlangus possibly, ref.5
Invertebrates containing Thiaminase
Bivalves: Bivalves such as clams can be a good food within a varied diet, but many contain a lot of Thiaminase & should not be used exclusively; some however, notably cockles, contain little Thiaminase & are consequently a better all-around food for mollusk-feeding predators such as pufferfish.
Ocean quahog or Black quahog (Artica islandica)
Clam (Tellina spp.)
but not oysters
Cherrystone, Chowder, Steamer clams (family Veneridae)
Pigtoe or bigtoe mussel (Pleurobema cordatum)
Scallop (Pecten grandis)
Hawaiian clam (sp. indet.; extremely high in thiaminase)
Blue mussel (Mytilus galloprovincialis)
Gastropods containing Thiaminase
Limpet (Helcioniscus sp.)
Cephalopods containing Thiaminase
Hawaiian flying squid (Nototodarus hawaiiensis)
Crustaceans containing Thiaminase
Prawn, Tiger shrimp (Penaeus spp.)
Shrimp Penaeus setiferus
Lobster ref.11
Freshwater Fish not containing Thiaminase
Cockles, tilapia, pollock, cod, haddock, the smelt sold as lancefish (couldn’t find what species this is). In general, N.A. sunfishes, flounders, cods & croakers are T.-free. Terrestrial foods in general, e.g. earthworms, bloodworms & crickets.
Family Centrarchidae (North American Sunfishes):
Largemouth bass (Micropterus salmoides)
Northern smallmouth bass (Micropterus dolomieu)
Northern rock bass (Ambloplites rupestris) aka rock perch, goggle-eye, red eye, & black perch, native to east-central North America. Has red eyes. Can be distinguished by the 6 spines in the anal fin vs 3 for other sunfish.
Blue gill (Lepomis macrochirus)
Pumpkinseed (Lepomis gibbosus)
Black crappie (Pomoxis nigromaculatus)
Family Percidae (Perches):
Yellow perch (Perca flavescens)
Perch Perca fluviatilis
Walleye or wall-eyed pike (Sander vitreus)
Family Salmonidae (Salmonids):
Chub or Bloater (Coregonus hoyi)
Lake trout (Salvelinus namaycush)
Rainbow trout (Oncorhynchus mykiss)
Rainbow Trout Salmo gairdnerii irideus
Brown Trout Salmo trutta fario
Most Salmonidae (trout, salmon, char etc.)
Other families:
Ayu sweetfish, a species of smelt (Plecoglossus altivelis) - family Plecoglossidae (Ayu fish)
Northern Longnose Gar (Lepisosteus osseus oxyurus) - family Lepisosteidae (Gars)
Northern Pike (Esox lucius) - family Esocidae (Pikes)
Tilapia various species
Brackish fish not containing Thiaminase
Family Salmonidae (Salmonids):
Cisco Lake herring (Coregonus artedi or a. areturus), Lake Superior
Atlantic Salmon (Salmo salar)
Coho salmon (Oncorhynchus kisutch)
Sea trout (Salmo trutta)
Other families:
Common eel (Anguilla anguilla) - family Anguillidae (True eels)
American eel aka Atlantic, black, Boston, bronze, common, freshwater eel - Anguilla rostrata
Pond smelt (Hypomesus olidus) - family Osmeridae (Smelts), f/w too
Marine fish not containing Thiaminase
Family Pleuronectidae (Righteye flounders):
Winter flounder, Black back, Lemon sole (Pseudopleuronectes americanus or a. dignabilis)
European plaice (Pleuronectes platessa)
American or Canadian plaice (Hippoglossoides platessoides)
Atlantic halibut (Hippoglossus hippoglossus)
Yellowtail flounder (Limanda ferruginea)
Family Gadidae (Cods & haddocks)
Atlantic cod (Gadus morhua)
Haddock (Melanogrammus aeglefinus or Gadus aeglefinus)
Saithe, Pollock (Pollachius virens & other spp.) P. virens & P. pollachius are called pollock (US) or Boston blue (not bluefish), coalfish/coley, podley & saithe (UK)
Family Sciaenidae (Drums or croakers):
Atlantic croaker (Micropogonias undulatus)
Southern kingfish, king whiting, ground mullet (Menticirrhus americanus)
Spot, Spot croaker (Leiostomus xanthurus)
Silver seatrout or white trout (Cynoscion nothus)
Sand weakfish or white trout too (Cynoscion avenarius)
Family Carangidae (Jacks):
Greater amberjack (Seriola dumerilii)
Yellowtail scad aka northern yellowtail scad, one-finlet scad, deep trevally & omaka (Atule mate)
Mackerel scad or Speedo (Decapterus pinnulatus = Decapterus macarellus)
Family Labridae (Wrasses):
Cunner (Tautogolabrus adspersus)
Tautog or blackfish (Tautoga onitis)
Family Scombridae (Mackerels, tunas, bonitos):
Atlantic mackerel aka Boston, Northern, Norwegian, Scottish mackerel or just mackerel (Scomber scombrus) (ref. 5 lists this fish as possibly containing thiaminase)
Kawakawa (Euthynnus affinis)
Other families:
European Bass Dicentrarchus or Morone labrax
Sole Solea solea
European Sprat (Sprattus sprattus), aka bristling, brisling, garvie, garvock, Russian sardine, russlet, skipper or whitebait
Cusk or tusk (Brosme brosme) - family Lotidae (Hakes & burbots)
Largehead hairtail, aka beltfish, ribbon fish, silver eel (Trichiurus lepturus) - family Trichiuridae (Cutlassfishes)
Piked dogfish (Squalus acanthias) - family Squalidae (Dogfish sharks)
Hake (Urophycis sp. of Pacific, Urophycis sp. of G. of Mexico) - family Phycidae (Phycid hakes)
Inshore lizardfish (Synodus foetens) - family Synodontidae (Lizardfishes)
Mullet Gulf of Mexico (Mugil spp.) - family Mugilidae (Mullets) except Flathead mullet (Mugil cephalus) see above
Scup, Porgy, Southern porgy (Stenotomus chrysops, S. aculeatus) - family Sparidae (Porgies)
Ocean perch, Redfish (Sebastes marinus) - family Sebastidae (Rockfishes)
Black seabass (Centropristis striata) - family Serranidae (Sea basses & Groupers)
Hardhead sea catfish (Ariopsis felis) - family Ariidae (Sea catfishes)
Sea robin (Prionotus spp.) - family Triglidae (Sea robins)
Silver hake or Whiting (Merluccius bilinearis) - family Merlucciidae (Merluccid hakes)
Hake Merluccius merluccius
Eyestripe surgeonfish (Acanthurus dussumieri) - family Acanthuridae (Surgeonfishes)
Atlantic blue marlin (Makaira nigricans) - family Istiophoridae (Billfishes)
Blotcheye soldierfish (Myripristis berndti) - family Holocentridae (Squirrelfishes, soldierfishes)
Glasseye (Heteropriacanthus cruentatus) - family Priacanthidae (Bigeyes or catalufas)
Great barracuda (Sphyraena barracuda) - family Sphyraenidae (Barracudas)
Skate Raja spp
Invertebrates not containing Thiaminase
Bivalves:
Cockle (Cardium spp.) (cockles contain little Thiaminase, per section “Invertebrates containing T.”)
Oysters
Crustaceans not containing Thiaminase
Marine shrimps (sp. indet.; Hawaii) – the only exception?
Portuguese crabs (sp. indet.)
Cephalopods not containing Thiaminase
Squid, Brief squid, calmar (Lolliguncula brevis)
Ref. 2: Guppies, mollies as feeder fish: Little or nothing is known about the thiaminase content of some of the small ornamental fishes usually used as feeders. However, goldfish & minnows (including rosy red minnows) definitely contain thiaminase & consequently make very poor choices as feeders. On the other hand, the Poeciliidae (e.g., guppies, mollies, mosquitofish) are often recommended as safe feeder fishes for predators because of their presumed to be low thiaminase content.
Despite claims among aquarists that guppies contain thiaminase producing bacteria, I am not aware of any scientific study demonstrating this to be the case. Since poecilids are grazers, an uptake of thiaminase-producing cyanobacteria would be possible, though less probable in a freshwater aquarium where a much smaller variety of algae are likely to be present than in the wild.
Anecdotal evidence that the notoriously delicate Ribbon Eel can live on a diet of mostly gut loaded black mollies for more than 15 years would seem to suggest that poeciliids are largely thiaminase-free & make a safe choice for feeder fish. Of course, this depends on the quality of the feeder fish being used, & cheap feeder guppies from pet stores might not contain any thiaminase but could certainly contain all sorts of pathogenic bacteria & parasites! So when poeciliids are described as being among the best feeder fish, this depends on them being bred at home & gut loaded with Vitamin B1-enriched foods, such as a good quality flake food. Because poeciliids have a high tolerance for saltwater (mollies in particular can be maintained indefinitely under marine conditions) they are equally useful in saltwater tanks as in freshwater aquaria. The thiaminase content of guppies is unknown, but considered low or negligible, making them much safer to use than goldfish or minnow feeders.
What to do with fishes not mentioned in the lists above?
1. Find out the scientific name of the food fish & compare it to the list again. Many fish are traded under obscure names.
2. Check literature by search engines.
3. If fail, treat the fish in question as if it contained thiaminase.
4. Can see if the fish in question belongs to the same genus or family as one or more of the fish enlisted. Yet, related fish from the same genus or family may have a similar composition in terms of protein or fat, but the thiaminase content sometimes seems to vary greatly even between species within a single genus & may even vary from population to population.
5. For management purposes (feeding of fish-eating animals) it should be assumed that all fish contain thiaminase (Ellen Dierenfeld, Wildlife Conservation Society, New York, USA)
Aren't Thiaminase containing fish eaten in the wild? Yes, they are, & this can cause predatory fish massive problems. The offspring of the Baltic Sea salmon, which apparently feed mostly on Thiaminase-rich herring & relatively little food that contains high levels of Vitamin B1, were found to suffer from Thiamine Deficiency. The eggs produced by adult salmon were provided with very little thiamin, & the fry almost all died soon after hatching. Comparable problems have been found among Salmonids in the N.A. Great Lakes, & this has been hypothesized to be related to a diet containing a large proportion of Thiaminase-rich alewives. However, most of the time predatory fish maintain a kind of balance between those prey fish rich in Thiaminase & those fish rich in Vitamin B1. If the predator has a reasonably varied diet, it should get enough Vitamin B1 to stay healthy.
The big problem for captive fish is that they are fed frozen fish.
Freezing does not affect Thiaminase & over time it will break down whatever Vitamin B1 is present in the frozen fish. Furthermore, any fish fed such frozen fish will be consuming the Thiaminase, & that will destroy some of the Vitamin B1 it already has. Making things even worse, freezing & thawing both break down some of the Vitamin B1 content of food as well.
Heating destroys Thiaminase but cooking food with heat also destroys a lot of the useful nutrients & piscivorous pet fish cannot stay healthy on cooked fish.
Many types of widely sold
live feeder fish contain a lot of Thiaminase but some types do not & even contain more Vitamin B1 than frozen foods, but feeders are expensive & more importantly there is a major risk of introducing pathogens e.g. Mycobacteria & endoparasites.
How can I avoid the thiamine deficiency syndrome?
1. Restrict feeding thiaminase containing fish to no more than 20% of all meals.
2. Avoid feeding exclusively frozen bivalves or shrimps, because these potentially have very high thiaminase content.
3. Avoid fish that was frozen for long periods (several months). Get small packages of food, & use them up quickly
4. Keep the diet generally as varied as possible! Remember, nutritional shortcomings in one type of food will be cancelled out by the other types of food, so the more types of food, the smaller the chance of nutrient imbalances.
5. Soak food in a vitamin product intended for pet fish prior to feeding at least once a week, more often when feeding lots of shrimps & bivalves!
References
1. National Research Council (1982): Nutrient Requirements of Mink & Foxes, Washington, D.C.: National Academy Press,
https://nap.nationalacademies.org/c...nd-foxes-second-revised-edition-1982#page_top
2. Marco Lichtenberger: Thiaminase & its role in predatory pet fish (and other piscivores) nutrition,
http://www.wetwebmedia.com/ca/volume_6/volume_6_1/thiaminase.htm
3.
https://www.theaquariumwiki.com/wiki/Thiaminase
4.
http://www.austinsturtlepage.com/Articles/Thiaminase.htm
5.
https://web.archive.org/web/2007090...ormation.org/S/00Chem/vitamins/thiaminase.htm
6. Anglesea, J.D. & Jackson, A.J. (1985): Thiaminase activity in fish silage & moist fish feed. Anim. Feed Sci. Tech. 13: 39-46.
Deutsch, H.F. & Hasler, A.D. (1943): Distribution of a Vitamin B1 destructive enzyme in fish.- Proc. Soc. Exp. Biol. Med. 53: 63-65.
Food & agriculture organization of the United Nations (1980): ADCP/REP/80/11 - Fish Feed Technology. HYPERLINK "http:]
www.fao.org/docrep/X5738E/x5738e00.HTM#Contents" http:]
www.fao.org/docrep/X5738E/x5738e00.HTM#Contents
Greig, R.A. & Gnaedinger, R.H. (1971): Occurrence of thiaminase in some common aquatic animals of the United States & Canada. Special Scientific Report—Fish. U.S. Dept. Commer. Natl. Mar. Fish. Serv. 631: 1-7.
Hilker, D.M. & Peter, O.F. (1966): Anti-thiamine activity in Hawaii fish.- J. Nutr. 89(4):419-421.
National Research Council (1981): Nutrient Requirements of Cold-water Fishes. Washington, D.C.: National Academy Press.
National Research Council (1983): Nutrient Requirements of Warm-water Fishes & Shellfishes. Washington, D.C.: Nat. Acad. Press.
National Research Council (1993): Nutrient Requirements of Fish. National Academy Press. Washington DC, USA.
Royes, J.-A.B. & Chapman F.A.: Preparing your own fish feeds.- University of Florida, 9 p. HYPERLINK "http:]edis.ifas.ufl.edu/pdffiles/FA/FA09700.pdf" http:]edis.ifas.ufl.edu/pdffiles/FA/FA09700.pdf
Scardi, V. & Magri, E. (1957): Thiaminase activity in Mytilus galloprovincialis.- Boll Soc Ital Biol Sper. 33(7):1087-1089 (in Italian).
Wistbacka, S.; Heinonen, A.; Bylund, G. (2002): Thiaminase activity of gastrointestinal contents of salmon & herring from the Baltic Sea.- Journal of Fish Biology 60(4), 1031-1042.
Yudkin, W.H. (1949): Thiaminase, the Chastek-paralysis factor.- Physiol. Rev. 29: 389-402.
7. Jonathan Crowe All About Thiaminase, Setting the record straight about thiaminase, the enzyme that causes vitamin deficiencies in fish-eating snakes.
http://www.gartersnake.info/articles/2012/all-about-thiaminase.php
8. R. Bitsch, Thiaminases & other Antithiamin Factors, Encyclopedia of Food Sciences & Nutrition (Second Edition), 2003.
9.
https://dailydogfoodrecipes.com/thiaminase-and-fish-everything-you-need-to-know/
10.
https://www.practicalfishkeeping.co...d-to-know-about-predator-fish-and-thiaminase/
11.
https://theholisticcanine17.com/tag/thiaminase-in-raw-fish/
Nutrient ranking of 159 Fish Highest in Thiamin (B1)
tools.myfooddata.com
Food Fish Highest in Thiamin (B1), Ranked by 100g Serving Size, 1.2mg = 100% DV
1. Pompano Florida Cooked Dry Heat 0.7mg (57% DV)
2. Pompano Florida Raw 0.6mg (47% DV)
3. Trout Mixed Species Raw 0.4mg (29% DV)
4. Burbot Cooked Dry Heat 0.4mg (36% DV)
5. Burbot Raw 0.4mg (31% DV)
6. Trout Mixed Species Cooked Dry Heat 0.4mg (36% DV)
7. Pike Walleye Raw 0.3mg (23% DV)
8. Salmon Atlantic Farmed Cooked Dry Heat 0.3mg (28% DV)
9. Cod Atlantic Dried & Salted 0.3mg (22% DV)
10. Mussel Blue Cooked Moist Heat 0.3mg (25% DV)
11. Tuna Fresh Bluefin Cooked Dry Heat 0.3mg (23% DV)
12. Fish Roe Mixed Species Cooked Dry Heat 0.3mg (23% DV)
13. Pike Walleye Cooked Dry Heat 0.3mg (26% DV)
14. Salmon Atlantic Wild Cooked Dry Heat 0.3mg (23% DV)
15. Mackerel Atlantic Raw 0.2mg (15% DV)
16. Mackerel Atlantic Cooked Dry Heat 0.2mg (13% DV)
17. Fish Roe Mixed Species Raw 0.2mg (20% DV)
18. Trout Rainbow Wild Cooked Dry Heat 0.2mg (13% DV)
19. Wolffish Atlantic Raw 0.2mg (15% DV)
20. Salmon Atlantic Farmed Raw 0.2mg (17% DV)
21. Catfish Channel Wild Raw 0.2mg (18% DV)
22.Fish Caviar Black & Red Granular 0.2mg (16% DV)
23. Eel Mixed Species Raw 0.2mg (13% DV)
24. Eel Mixed Species Cooked Dry Heat 0.2mg (15% DV)
25. Salmon Atlantic Wild Raw 0.2mg (19% DV)
26. Salmon Sockeye Cooked Dry Heat 0.2mg (13% DV)
27. Shad American Raw 0.2mg (13% DV)
28. Spot Raw 0.2mg (13% DV)
29. Abalone Mollusks Mixed Species Raw 0.2mg (16% DV)
30. Abalone Mixed Species Cooked Fried 0.2mg (18% DV)
31. Mussel Blue Raw 0.2mg (13% DV)
32. Tuna Fresh Bluefin Raw 0.2mg (20% DV)
33. Catfish Channel Wild Cooked Dry Heat 0.2mg (19% DV)
34. Salmon Nuggets Breaded Frozen Heated 0.2mg (17% DV)
35. Salmon Nuggets Cooked As Purchased Unheated 0.2mg (16% DV)
36. Shad American Cooked Dry Heat 0.2mg (15% DV)
37. Spot Cooked Dry Heat 0.2mg (15% DV)
38. Whitefish Mixed Species Cooked Dry Heat 0.2mg (14% DV)
39. Wolffish Atlantic Cooked Dry Heat 0.2mg (17% DV)
40. Yellowtail Mixed Species Cooked Dry Heat 0.2mg (15% DV)
41. Clam Mixed Species Cooked Moist Heat 0.2mg (13% DV)
42. Oyster Eastern Cooked Breaded & Fried 0.2mg (13% DV)
43. Oyster Eastern Canned 0.2mg (13% DV)
44. Herring Atlantic Raw 0.1mg (8% DV)
45. Herring Atlantic Cooked Dry Heat 0.1mg (9% DV)
46. Mackerel King Raw 0.1mg (8% DV)
47. Mullet Striped Raw 0.1mg (8% DV)
48. Mullet Striped Cooked Dry Heat 0.1mg (8% DV)
49. Pike Northern Cooked Dry Heat 0.1mg (6% DV)
50. Sablefish Raw 0.1mg (8% DV)
51. Salmon Coho Wild Raw 0.1mg (9% DV)
52. Salmon Coho Wild Cooked Moist Heat 0.1mg (10% DV)
53. Salmon Pink Raw 0.1mg (7% DV)
54. Sardine Atlantic Canned In Oil Drained Solids With Bone 0.1mg (7% DV)
55. Scup Raw 0.1mg (9% DV)
56. Sea Bass Mixed Species Raw 0.1mg (9% DV)
57. Shark Mixed Species Cooked Batter-Dipped & Fried 0.1mg (6% DV)
58. Sturgeon Mixed Species Cooked Dry Heat 0.1mg (7% DV)
59. Sturgeon Mixed Species Smoked 0.1mg (8% DV)
60. Sunfish Pumpkin Seed Raw 0.1mg (7% DV)
61. Tilefish Cooked Dry Heat 0.1mg (12% DV)
62. Trout Rainbow Wild Raw 0.1mg (10% DV)
63. Tuna Fresh Yellowfin Raw 0.1mg (10% DV)
64. Whiting Mixed Species Cooked Dry Heat 0.1mg (6% DV)
65. Yellowtail Mixed Species Raw 0.1mg (12% DV)
66. Oyster Eastern Farmed Raw 0.1mg (9% DV)
67. Oyster Eastern Farmed Cooked Dry Heat 0.1mg (11% DV)
68. Tilapia Cooked Dry Heat 0.1mg (8% DV)
69. Trout Brook Raw New York State 0.1mg (11% DV)
70. Herring Atlantic Kippered 0.1mg (11% DV)
71. Herring Pacific Raw 0.1mg (5% DV)
72. Ling Raw 0.1mg (9% DV)
73. Anchovy European Raw 0.1mg (5% DV)
74. Anchovy European Canned In Oil Drained Solids 0.1mg (7% DV)
75. Mackerel Pacific & Jack Mixed Species Raw 0.1mg (9% DV)
76. Bass Fresh Water Mixed Species Raw 0.1mg (6% DV)
77. Mackerel Spanish Raw 0.1mg (11% DV)
78. Carp Cooked Dry Heat 0.1mg (12% DV)
79. Mackerel Spanish Cooked Dry Heat 0.1mg (11% DV)
80. Catfish Channel Cooked Breaded & Fried 0.1mg (6% DV)
81. Pout Ocean Raw 0.1mg (7% DV)
82. Cod Atlantic Canned Solids & Liquid 0.1mg (7% DV)
83. Perch Mixed Species Raw 0.1mg (6% DV)
84. Perch Mixed Species Cooked Dry Heat 0.1mg (7% DV)
85. Pike Northern Raw 0.1mg (5% DV)
86. Croaker Atlantic Raw 0.1mg (6% DV)
87. Pollock Alaska Cooked Dry Heat (May Contain Additives To Retain Moisture) 0.1mg (5% DV)
88. Sablefish Smoked 0.1mg (11% DV)
89. Salmon Chinook Raw 0.1mg (5% DV)
90. Halibut Atlantic & Pacific Raw 0.1mg (4% DV)
91. Halibut Atlantic & Pacific Cooked Dry Heat 0.1mg (5% DV)
92. Crab Alaska King Cooked Moist Heat 0.1mg (4% DV)
93. Salmon Sockeye Raw 0.1mg (11% DV)
94. Crab Blue Raw 0.1mg (7% DV)
95. Sea Bass Mixed Species Cooked Dry Heat 0.1mg (11% DV)
96. Crayfish Mixed Species Wild Raw 0.1mg (6% DV)
97. Seatrout Mixed Species Raw 0.1mg (5% DV)
98. Crayfish Mixed Species Wild Cooked Moist Heat 0.1mg (4% DV)
99. Snapper Mixed Species Cooked Dry Heat 0.1mg (4% DV)
100. Sturgeon Mixed Species Raw 0.1mg (6% DV)
101. Swordfish Raw 0.1mg (6% DV)
102. Swordfish Cooked Dry Heat 0.1mg (7% DV)
103. Tilefish Raw 0.1mg (10% DV)
104. Oyster Pacific Raw 0.1mg (6% DV)
105. Turbot European Raw 0.1mg (6% DV)
106. Whitefish Mixed Species Raw 0.1mg (12% DV)
107. Whiting Mixed Species Raw 0.1mg (5% DV)
108. Salmon Coho Farmed Raw 0.1mg (8% DV)
109. Salmon Coho Farmed Cooked Dry Heat 0.1mg (8% DV)
110. Bass Striped Cooked Dry Heat 0.1mg (10% DV)
111. Trout Rainbow Farmed Raw 0.1mg (10% DV)
112. Bluefish Cooked Dry Heat 0.1mg (6% DV)
113. Trout Rainbow Farmed Cooked Dry Heat 0.1mg (12% DV)
114. Salmon Coho Wild Cooked Dry Heat 0.1mg (6% DV)
115. Butterfish Cooked Dry Heat 0.1mg (12% DV)
116. Conch Baked Or Broiled 0.1mg (5% DV)
117. Halibut Greenland Cooked Dry Heat 0.1mg (6% DV)
118. Herring Pacific Cooked Dry Heat 0.1mg (6% DV)
119. Ling Cooked Dry Heat 0.1mg (11% DV)
120. Mackerel King Cooked Dry Heat 0.1mg (10% DV)
121. Pollock Atlantic Cooked Dry Heat 0.1mg (5% DV)
122. Pout Ocean Cooked Dry Heat 0.1mg (8% DV)
123. Scup Cooked Dry Heat 0.1mg (11% DV)
124. Seatrout Mixed Species Cooked Dry Heat 0.1mg (6% DV)
125. Octopus Common Cooked Moist Heat 0.1mg (5% DV)
126. Bass Striped Raw 0.1mg (8% DV)
127. Bluefish Raw 0.1mg (5% DV)
128. Butterfish Raw 0.1mg (10% DV)
129. Carp Raw 0.1mg (10% DV)
130. Cisco Raw 0.1mg (7% DV)
131. Cod Atlantic Raw 0.1mg (6% DV)
132. Drum Freshwater Raw 0.1mg (6% DV)
133. Grouper Mixed Species Raw 0.1mg (6% DV)
134. Halibut Greenland Raw 0.1mg (5% DV)
135. Crab Queen Raw 0.1mg (7% DV)
136. Shrimp Mixed Species Cooked Breaded & Fried 0.1mg (11% DV)
137. Squid Mixed Species Cooked Fried Calamari 0.1mg (5% DV)
139. Frog Legs Raw 0.1mg (12% DV)
VITAMIN B1 IN FOOD:
Which marine fish have the most vitamin B1? Leaf ima 0.22 mg vitamin B1 (thiamin, Aneurin) . Mackerel ima 0.15 mg vitamin B1 (thiamin, Aneurin) . Hake ima 0.08 mg vitamin B1 (thiamin, Aneurin) . Cod (fresh) ima 0.06 mg vitamin B1 (thiamin, Aneurin) . Herring (fresh) ima 0.06 mg vitamin B1...
world-population.net
Which marine fish have the most vitamin B1 per 100g?
1. Leaf 0.22 mg
2. Mackerel 0.15 mg
3. Hake 0.08 mg
4. Cod (fresh) 0.06 mg
5. Herring (fresh) 0.06 mg
6. Sardine 0.06 mg
7. Tuna (fresh) 0.05 mg
8. Canned tuna 0.05 mg
9. Herring (smoked) 0.04 mg
10. Sardines (whole canned in water) 0.02 mg
11. Sardines (fresh) 0.00 mg
12. Gilthead 0.00 mg
13. Surmullet 0.00 mg
14. Herring (marinated) 0.00 mg
15. Devilfish 0.00 mg
Which freshwater fish have the most vitamin B1?
1. Sprout 0.20 mg
2. Salmon (fresh) 0.17 mg
3. Eel (fresh) 0.15 mg
4. Pike 0.15 mg
5. Eel (smoked) 0.14 mg
6. Carp 0.09 mg
7. Trout 0.09 mg
8. Perch 0.08 mg
9. Canned salmon 0.03 mg
10. Gudgeon 0.00 mg
11. Sturgeon 0.00 mg
12. Dace 0.00 mg
Okay, let's talk about Hole in the Head. What causes it? - You will hear a million different theories - ready to hear mine? years of collective research and gathering opinions with an open mind has led me to these conclusions.. Simply put, 'Hole in the Head' and 'Lateral Line Erosion' are...
www.monsterfishkeepers.com
Thiaminase destroys Thiamine (Vitamin B1). Goldfish & Rosie Reds (and most cyprinidae) contain a very high level of thiaminase. Thiamine deficiency can lead to a myriad of problems including neurodegeneration, wasting and death. Tissue Distribution in many living animals is dependent on Thiamine levels. Once Thiaminase is ingested, it has very long-lasting effects and does not purge itself from the body. Lack of Thiamine (Vitamin B1) is the primary reason why fish would not be able to properly produce fleshy tissue. - VJ: and according to the author one common reason behind the HITH disease.
Well, the initial post is indeed interesting, and there have been studies that support the fact that thiaminase heavy diets can be detrimental to fish. http://afs.allenpress.com/perlserv/?request=get-pdf&doi=10.1577%2FH03-078.1 This is a peer-reviewed scientific article about thiamine...
www.monsterfishkeepers.com
Well, the initial post is indeed interesting, and there have been studies that support the fact that thiaminase heavy diets can be detrimental to fish.
This is a peer-reviewed scientific article about thiamine deficiency causing early mortality syndrome in salmonids. Therefore, we can surmise that thiaminase is not broken down by the stomach acids and is either retained in the gut or absorbed through the walls of the gut.
Thiaminase heavy diets also seem to affect alligators, as this paper details:
However, the effects of thiaminase alone are not the sole cause of mass mortality in alligators as this next paper argues:
Therefore, while high levels of thiaminase does have an effect on a fish's (or reptile's) physiology, the exact level of the effect is uncertain. Moreover, thiaminase is obviously dealt with by different kinds of fish differently. Fish that don't normally ingest large amounts of thiaminase can obviously not be expected to deal with large concentrations of it well. Likewise, fish that normally ingest large amounts of it will have evolved a physiological way to dispose of it.
I also noticed that thiamine deficiency seems to be affect central nervous systems most severely, and so don't understand the argument that it's preventing fish from producing adequate fleshy tissues etc.?
http://afs.allenpress.com/perlserv/....1577/1548-8667(1995)007<0269
ABMOT>2.3.CO;2
Granted, the papers I just linked you to go into examples of deformed fry, but in my mind, none of those deformities are pertinent to the sensory pores that HLLE affects.
Studies involving thiamine deficiencies and humans also center around brain disorders and central nervous system affects. I realize that humans do not have the same sensory apparatus us fish, nor the same physiology, but if reptiles and mammals appear to express thiamine deficiency in a similar manner, as well as some fish fry, what are the odds that adult cichlids in particular will express the disorder in a different manner?
In fact, the below link mentions nothing about sensory pores despite mentioning nervous disorders and hemorrhaging...
