Worms

[Spiderman]

I shot a bass recently and when we ate it we found a few worms in the flesh. They were dark and tightly coiled; approx 1mm diameter and coiled into a coil of about 5mm. I did some searching with Google and found that they are probably a roundworm called Phocanema decipiens. This was the first time I have found worms in a fish and I was wondering whether others had had the same experience and whether particular species or locations are more affected than others?

 

[abusingelves]

this link seems to say that there is really no danger as long as you thoroughly cook the fish. sounds a bit sketchy to me.

Seafood Network Information Center

as a half cooked medic myself i have done a college module on parasites in various foods and other intestinal parasites which are nasty to think about, but in reality cause only minor 'real' discomfort. the main ones seem to be the lung fluke, contracted from eating under/un cooked crustacea, but as far as i know that's confined to asia.

i have found white nematode (round) worms in wrasse on more than one occasion, but that was when using them as lobster bait. needless to say, i didn't feel compelled to eat them. :yack i've also seen them in mackerel and if i remember correctly herring. think i saw them in a few big pollock aswell.

the stuff below i got off a website, but will root out some more info when i get home tonight. but like i said, they didn't tell us about any human contraction of parasites from fish in these parts, so i'd presume it would be rare (very)

Infected fish. Eating raw or insufficiently cooked fish [Latin American ceviche, Japanese sushi and sashimi, Dutch maatjesharing (herring), Norwegian gravlax (salmon), Hawaiian lomi-lomi (raw salmon), Spanish boquerones (anchovies in vinegar)] may lead to infection with: (1) nematodes such as Anisakis or Pseudoterranova larvae, Capillaria philippinensis, Gnathostoma; (2) cestodes such as Diphyllobothrium (fish tapeworm) and Diplogonoporus; (3) trematodes such as Metagonimus and Heterophyes (small intestinal flukes), Clonorchis and Opisthorchis (liver flukes).
Infected crabs and crayfish. Eating larvally infested, raw or insufficiently cooked crabs may lead to paragonimiasis (lung fluke).

 

[sunfish]

Pollack almost always have worms in the flesh as do cod and indeed these are called codworms. I think they are anasakis but I'm no expert. If you look closely at the inside of a fillet in the area of the belly flaps you will see some brown spots. Dig one out with the point of your knife and you will find it is a coiled up worm. Hope I hanen't put you all off eating fish. They are harmless as long as the fish is cooked and I never even think about them unless I'm going to make ceviche or something else uncooked. Google anasakis to find out more.

 

[paddyc23]

I found a lice type grub in some species deep in there throat, wen the fish is alive you dont see them and once to fish is dead this lice type grub climbs out of its throat and mouth, depending on the size of fish, small grubs small fish and big ones for big fish, it almost looks like a big wood lice, its white in colour and has about 8-10 legs and 2 big claws on its head, very weird, sometimes there are 2 or 3 lice in one fish, a mother and a few babies, any ideas for this typ of grub?

 

[abusingelves]

ok found some info. this stuff is not specificaly europe oriented.

This is a clinical scenario I found in some of my notes.

CASE: man presents with chronic diarrhoea and fatigue. Full blood count shows a megaloblastic anaemia, diphylobothrium latum Is identified as the cause.

EXP: B12 deficiency Is associated with infection with the fish tapeworm, found in Scandinavia and the great lakes. The adult worm attaches to the mucosa of the small intestine and releases eggs into the faeces. Crustacean living in contaminated water ingest the free swimming larvae which hatch from the eggs. Fish ingest the crustaceans and then humans become infected by eating undercooked fish . the B12 deficiency results from the tapeworm absorbing B12 from the intestinal lumen.

 

[atomichaggis]

Pretty much all fish in the sea have some parasites both ecto and endo.
some common ones like anasakis can cause harm to humans but its easilly prevented by freezing the fish prior to eating or cooking thoroughly... thats why most cases of human illnesses due to fish parasiteslike this are in Japan.

recently there was a recommendation for fishermen in the med to freeze their fish after a number of people got ill.

 

[naiad]

I found a lice type grub in some species deep in there throat, wen the fish is alive you dont see them and once to fish is dead this lice type grub climbs out of its throat and mouth, depending on the size of fish, small grubs small fish and big ones for big fish, it almost looks like a big wood lice, its white in colour and has about 8-10 legs and 2 big claws on its head, very weird, sometimes there are 2 or 3 lice in one fish, a mother and a few babies, any ideas for this typ of grub?

It is an isopod (Cymothoa sp.), a crustacean related to woodlice and water lice. It eats the tongue of the fish, and then lives in the place where the tongue would be. The fish usually lives a normal life with the isopod instead of its tongue. It is not dangerous to humans (unless someone has a tale about diving with their mouth open and ending up being mistaken for a fish!).

Tongue-eating lice hit catfish farm | Practical Fishkeeping magazine
UnderwaterTimes.com :: View topic - Fish Tongue-Eating Parasite Spreading?

 

[octopus]

Interesting topic. I have extracted few advisory notes.

Thorough cooking destroys harmful bacteria and parasites. A rule of thumb is to cook fish 10 minutes for every inch of thickness.

Don't eat raw fish unless it has been frozen solid to destroy parasites. Large fish may take 48 hours at 0°F to freeze solidly. Improper smoking methods may result in undercooked, unsafe fish. Lightly marinated or salted raw fish recipes may be unsafe unless the fish has been frozen. Do not eat any fish unless it has been heated sufficiently or solidly frozen at some point in preparation.

On slightly different note:

Fishing regulations prohibit mutilating fish in the field so that its size or species cannot be determined by officials. Even though your fish may be in a cooler in your car trunk, the fish may still be considered "in the field" by your state fish and game enforcement agency. Consider leaving the tail, fins, and head on the fish until you get home.

Source:
Handling Sportcaught Fish, EC 1414

If using raw fish for sushi, sashimi, or ceviche, freeze it at 0°F or lower for at least 24 hours (or buy previously frozen) to destroy potential parasites.

Source:
www.wholefoodsmarket.com/foodsafety/seafood.html

The US regulations stipulate that the freezing process to destroy parasites should be -20C for 7 days or -35C for 15 hours (FDA, 2001).

Source:
http://www.rikilt.wur.nl/NR/rdonlyres/BDEEDD31-F58C-47EB-A0AA-23CB9956CE18/44179/R2007006.pdf

 

[sunfish]

I wonder which of the last two extracts is more accurate. 0F for 24 hours I can do but 7 days? I don't think my freezer will even approach -20. I do like ceviche though.

 

[shoutatthesky]

I don't eat any other fish than farmed salmon or trout(wild or farmed). Are these known to contain many parasites?

 

[deep thinker]

I think that should they have a parasite in the farmed fish scenario, you should get more fish contaminated by such a parasite due to the close proximity of the fish. Then again they probably clean their dams and pools regularly and fine filtering their water. Parasites also probably gets picked up by means of QC if they have that...

 

[shoutatthesky]

I think that should they have a parasite in the farmed fish scenario, you should get more fish contaminated by such a parasite due to the close proximity of the fish. Then again they probably clean their dams and pools regularly and fine filtering their water. Parasites also probably gets picked up by means of QC if they have that...

I should mention that most of the fish farmed in this part of the country is housed in nets situated in the ocean so there is a steady and continual replacement of water around the fish. Proximity however probaly would create a higher risk of the spread of parasites.
This is where I get my salmon from -
The Art of Raising and Preparing New Zealand King Salmon - The New Zealand King Salmon Company

 

[Spiderman]

I don't eat any other fish than farmed salmon or trout(wild or farmed). Are these known to contain many parasites?

I think I'm right in saying that eating farmed fish reduces your risk of parasites but increases your intake of the various chemicals used to keep the fish healthy

 

[atomichaggis]

I don't eat any other fish than farmed salmon or trout(wild or farmed). Are these known to contain many parasites?

Fish farms are the bane of migratory salmonid stocks worldwide.
They are a breeding ground for lice wich have decimated wild stocks in Ireland, Scotland and Norway.
Any number of salmonids on their first migration to the sea are eaten alive by the lice.
If they all went out of business tomorrow, I'd be a happy man.

To answer the original question... in pens they are fed pellet and artificial feed wich helps take things like anasakis out of its food chain but they are still fish in the sea and if a bit of seal crap washes by their pen then... yeah they can still get parasitic infections. any number of wild trout I catch have parasites in their gut and pretty much all have the damned sea lice(not harmful to humans) on their skin.

I'm a pretty obsessive fisherman and I'm usually up to My elbows in fish guts and I eat a helluva lot of fish. pretty much all of them have parasites of some description... but it its not a problem.
Hygienic handling and preparation of work surfaces is a bigger issue. You are more likely to get ill off Your cutting board than a freshly caught fish.
At least if You catch Your own you know it has been gutted swiftly and prepared properly and either frozen or cooked thoroughly.

Don't worry about parasites! just use common sense when preparing them... as for farms... Boycott!

 

[Spiderman]

Don't worry about parasites! just use common sense when preparing them

Cooked worms don't worry me, but my wife finds it hard to enjoy eating bass (which she loves) when she is picking out worms!

 

[atomichaggis]

Cooked worms don't worry me, but my wife finds it hard to enjoy eating bass (which she loves) when she is picking out worms!

Thats an aesthetic issue like Scars or tumours on fish, just pick em out. Should be easy to spot if you fillet them first.
Fish is good food but preperation ain't for the squeamish.

 

[abusingelves]

on the point of salmon farms, i was under the impression that the pellets fed to the fish by the majority of salmon farms was itself made of fish meal. and fish meal is indeed not exactly sustainable.

the link posted by southatthesky points out that the salmon on that particular farm are fed food from sustainable sources. that sounds good, but then again the aussies and new zealanders are way ahead of us on conservation. 'correct me if i'm wrong'.

sealice are a huge prblem. i've seen pollack with a good few of them. these fish can look much thinner than they should for their length, so i presume they affect other fish stocks, and not just salmon and trout.

 

[atomichaggis]

on the point of salmon farms, i was under the impression that the pellets fed to the fish by the majority of salmon farms was itself made of fish meal. and fish meal is indeed not exactly sustainable.

the link posted by southatthesky points out that the salmon on that particular farm are fed food from sustainable sources. that sounds good, but then again the aussies and new zealanders are way ahead of us on conservation. 'correct me if i'm wrong'.

sealice are a huge prblem. i've seen pollack with a good few of them. these fish can look much thinner than they should for their length, so i presume they affect other fish stocks, and not just salmon and trout.

It takes slightly more wild reared protein to produce a given amount of farm reared fish protein... even with the wildly varied numbers thrown around its Not a huge issue really considering other commercial fishing activities(I.E. beam/pelagic trawls), tho not exactly a sound practice.

The sea lice do affect almost every fish, tho some more than others. Salmonids are at particularly serious risk on their first migration to the sea though and stocks worldwide are being seriously depleted. The state of some of the small trout I catch is heartbreaking.
I noticed this spring that other species were crawling with Lice too.
Haddock, cod, pollack, coalies all got em, flatties got em and Gurnards are particularly bad with them, probably due to slime. I haven't seen anything that suggested lice were a serious threat to any of these fish... can't exactly be good for them though judging by their general condition.

 

[shoutatthesky]

as for farms... Boycott!

The reason I eat only farmed fish is because the fishing industry has raped and pillaged the sea to the point where I don't feel comfortable supporting them. I have no problem with people who catch fish for there own and their families use - in fact spearfishing is probaly the most ecologically sound method as you can take just the best fish, not the undersized ones that you then have to throw back into the sea wounded by a hook having been pierced through their mouth or other part of their body.
It is my personal choice to abstain from all wild fish (excepting trout because they are an introduced species here). I would rather just swim with them.
I didn't know that about the effect of farms on wild populations and shall look further into it.

 

[atomichaggis]

The reason I eat only farmed fish is because the fishing industry has raped and pillaged the sea to the point where I don't feel comfortable supporting them. I have no problem with people who catch fish for there own and their families use - in fact spearfishing is probaly the most ecologically sound method as you can take just the best fish, not the undersized ones that you then have to throw back into the sea wounded by a hook having been pierced through their mouth or other part of their body.
It is my personal choice to abstain from all wild fish (excepting trout because they are an introduced species here). I would rather just swim with them.
I didn't know that about the effect of farms on wild populations and shall look further into it.

Finding something to eat that sits well with ones own ethical standpoint is a minefield nowadays, even Danish bacon harms the british coastline!
Spearing is undoubtedly the most sound way of catching fish... providing for clean shots of course.
Rod and line has got to be second, You can eat all the fish you catch and stop when you have enough or selectively fish for big fish simply by using bigger hooks or lures and fish mortality can be prevented in most cases when returning unwanted fish to the water.
In either of these methods, waste is minimal... just a fraction of the percentages wasted by most common commercial methods.

Then there is the issue of food miles. How sound is a fish from a sustainable fishery if it travelled 1000 miles in a truck to the supermarket?

I'm all for locally caught fish speared and rod and line caught, Both Methods sit well with My conscience... s'pose I'm a bit spoiled living by the sea and catching My own but there are sometimes commercial line caught fish (not longlined) and speared fish on offer in coastal towns and inland fishmongers might be open to suggestions of buying in fish that are not pressured or commercially targeted.

You might find that a lot of Your coatal fish there in NZ aren't pressured or targeted commercially and you can add a little variety to your own fish consumption with a clear consciense... worth checking out.