I'm a member of a club in the North-East of England who regularly stock one of our lakes exclusively with Brownies.

A recent sampling campaign by members found that around 60% of fish caught had intestinal worms.

After sending samples off to the 'E.A'. for analysis it was found that these are a form of 'Tapeworm' which are present in our plentiful minnow population and thence transferred to our stockfish.

We are now faced with a dilemma re future stocking policy: If we continue to stock with Browns, those fish which have spent a while in the lake wthout being caught will inevitably pick-up these worms and the cycle will continue.

I was wondering if 'Rainbows' are more resilient to this type of infestation than 'Browns' and, if so, if we switch to 'bows and attempt to get them out a.s.a.p. after stocking so that the worms don't have time to 'take-hold' would this go towards solving our problem.

Are there any 'Marine Biologists' out there or members who have also suffered this problem?

Any advice would be greatly appreciated.

do you know what species of worm you have ??

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I'm pretty certain that the Rainbows would pick up the tapeworm as well,Did the EA not give you any advice.

Jim

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The Fishermans Friend is the Flirty Fly,Fickle Food for Fleeting Fish.

possible but not nessasarily the case jim... i studied molecular parasitology for 3 years

the problem you have is that dependant on the species there will be a vector for the infection... for example in the cestode C. truncatus gammerus is an intermediate host , the the cyst of the worm develops in the haemocoel of the shrimp (fluid filled body cavity) and matures for around 10 days, it then starts to produce chemicals which change the shrimps behaviour which will make it more likely to be picked off my a fish, insuring the worm is transmitted to the final host...,
it would be a tough one to get rid of short of electro fishing regularly to empty the lke then leaving it fallow (almost impossible to do) or treating wth medication to break the life cycle... gimme a species and i will find out what i can

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I bow to your vastly superior knowledge.

jim

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The Fishermans Friend is the Flirty Fly,Fickle Food for Fleeting Fish.

Mematoade(sp) worm can be introduced to your waterby sea guls. Roadford lake in devon has this problem BIG TIME and has had for some years. Once the fish is dead the worm moves out from the stomach and into the flesh of the fish.
Rod.

I was told quite a few years ago that rainbow trout are not affected by this worm. I know a water where the brownies have worms, but the rainbows don't. you may have to go down the line of stocking rainbows, that would be a pity.
Billy.

...on the other hand, such problems are sometimes reported with trout in completely wild systems from time to time, they're often reported as being cyclical although I'm not sure if that's true. What I'm saying is that the situation may not be static (and might improve). If you can get the species, I'd be interested in hearing what Icky says.

Come to think of it, I've never noticed a heavily parasitised rainbow but maybe that's because the bulk of the rainbows we catch are simply not at large for long enough to pick up a noticable burden (or they generally occupy a different dietary niche)? Wouldn't it be fair to say that most wild trout of "takeable" size will be parasitised to some extent (if we but cared to look)? I've never let it put me off eating a fish (if I kill one it is a duty!), although I tend not to eat them raw...

Would there be a lot of coarse fish in the lake seem they have an adverse affect on stocked trout.

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I will arise and go now, and go to Innisfree,9 bean rows will I have there and a hive for the honey bee.

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