Parasitic Worm affecting Megalechis thoracata

[Dee]

Hello everyone, I'm hoping that you can all help me with a problem that has me at the end of my tether. Both of my

Megalechis thoracata

have what appears to be a parasitic worm protruding from the anus. The worms are white, on one hoplo it is protruding just under 1cm and on the other maybe 4mm. In both cases it is about 2mm thick. It appears to be a single worm protruding in both cases. One fish is behaving normally, the other has been steadily going downhill as I attempt to treat the problem.

I have tried the following medications:
Waterlife Sterazin
Kusuri Wormer Plus (flubendazole)
Fluke-Solve Aquarium (praziquantel)
Chanaverm (levamisole hydrochloride)

All of these wormers have been used for 2 courses of treatment except for Chanaverm which claims on the packaging I should wait several weeks before treating again (I am dubious of this claim). I am now at a bit of a loss for what to try. I would be happy to attempt to extract the worms, but I really am not experienced enough to know if this is a good idea or if it will cause serious harm to the fish. I have been attempting to get a picture of the parasite, but the fish are either swimming around too fast or sitting on top of it.

In addition, here are my tank stats:
Temperature range - 25 degrees Celcius
pH - 7.2
GH - 60 - 80 (test has a mg/l scale)
KH - 70 - 80 (test has a mg/l scale)
Ammonia - 0 before and after water change
Nitrate - 5 before water change, 0 after
Nitrite- 0 before and after water change
25% water changes are performed twice weekly. Looking back at my test records my results look stable.

The tank is a 260l fluval running a fluval 305 canister filter, usually I run this with carbon and zeo-carb media as well but have removed those while medicating. It has a thin layer of fine gravel substrate, some bogwood with plants and a few pleco caves and tunnels for good measure. The tank has been running for just over one year. Tankmates are all other cats and are listed in full on my aquaria, but there's never been any problems with them not getting along. A good few of them are certainly wild caught however (for example

Microglanis carlae

)

I would be very grateful for any and all help.

[Mike_Noren]

The worm is probably the roundworm Camallanus, and the recommended treatment is levamisole hydrochloride, although several other antihelminths have apparently worked.

Sterazin and praziquantel should have no effect against roundworms, and I have a vague memory that flubenol is only effective if ingested or combined with a substance like DMSO which allows chemicals to pass through the skin (though a quick search suggests that acetone can be used as a replacement for DMSO), but levamisole hydrochloride should have killed them. You may have used too low dose, or your worms may be resistent. Another possibility is that there's a problem with Wormer Plus, so possibly you just need to test another brand.

[Dee]

Hi Mike_Noren, thanks for your reply. I read through your link about levamisole hydrochloride and had a look at the medicine I used which contains it, which is the Chanaverm. I checked the packaging and I have given an equivalent Levamisole dose rate of 2mg/l - which is in line with the veterinary suggestions in your link, but the author suggests a much higher dose can be safely applied - up to 30mg/l for catfish for 24 hours followed by a 75% water change.

Armed with that I'm going to try and track down some more levamisole (which was not the easiest to find) and try this again at a higher dosage. Thanks very much for the useful information.

[joemc]

i would agree it sounds like Camallanus worm, i suffered an outbrake of them a few years back and they broke my heart trying to get rid of them, i brought them in on a group of bolivian rams i bought, in the end i used Sera Nematol, i followed the instructions on the pack and that was the end of them, i have since reccomended this product to some other fishkeepers and all have said it worked, easy to dose and it works!

[Mike_Noren]

Sera Nematol

That one was new to me, I searched the net and its active ingredient is emamectin benzoate. Emamectin bensoate is an insecticide, and since it kills all arthropods it's been used to control anchor worms and fish lice, but I did not know it had effect against roundworms.

[JEK]

There was recently a similar case in a certain aquarium related forum. The assumed parasite was actually a male genital papillae.. Clearly visible in this picture from catelog http://www.planetcatfish.com/catelog/_i ... age_id=582

Might not be the case here but just saying..

[Dee]

Well at the risk of sounding (and being) rather silly, that does look like it JEK I am really very embarrassed that this is something I did not learn about my fish. I think I'll spend the rest of the evening covering my bases with the other species I keep! I'm sorry to have wasted everyone's time with medication recommendations but I feel I've improved my knowledge about different medications in the process so I'm still very grateful to be clear!

However, this is a bit scary as it means I have no clue what is wrong with my sick hoplo. He was unwell before I commenced medication and the tank stats in my records were steady at that time. Him being unwell is what caused me to scrutinise him and wrongly identify worms as the cause.

He was off his food, skittish (swimming very suddenly from one end of the tank to the other, occasionally seeming out of control) and has taken to hiding most of the time. I realise that this may have been made worse by my stupid medicating, but he has had clean, unmedicated water for the best part of a week now, and while he is seemingly not getting worse, neither is he getting better - I have not seen him eat in quite a while.

[Marc van Arc]

So you have 2 males in spawning mood. Could it be that the "sick" one is being bullied by the other and therefore behaves differently from what you are used to?

[Richard B]

Hey there - absolutely no need to be sorry or embarrassed in any way at all - we are all here to help in any way we can. You've certainly not wasted anyone's time and it is always best to be safe not sorry.

As to the problem, clean well oxygenated water can only be of benefit. Hopefully one of the better informed keepers of this fish might see your thread and chip in.

[Dee]

Perhaps that is it. I guess skittish behaviour, going off food and hiding all the time would all fit with that. My only reservation about that theory is I haven't seen the other hoplo bothering him at all.

They used to swim about together and seemed fine, nothing aggressive. But I understand if they have come into a spawning mood maybe that has changed and I have missed the bullying happening.

One question since I'm way out of my depth here - is there any reason why the genital papillae would be more visible on the sick one (all the time, as far as I can tell) and not on the healthy one?

[Dee]

Thanks Richard B - I'm certainly learning a lot! I will keep on top of the tank cleaning and have had the filter outlets set to disrupt the surface of the water as much as possible, I'm also going to see if I can get an airstone tomorrow to help.

[Dee]

Just as a follow up to my other question, I've managed to take some pictures as sick hoplo is out at the front of the tank for the first time in about a week, still not looking too clever or seeming to eat though

Here is sick hoplo in his current state. Although it can't be seen, his male genital papillae appears the same as the one in the picture JEK linked to in the post further up.


Here is the healthy hoplo, which the same area I can see something, but much smaller.


Also a zoom in on the same picture to show what I can see, this is about as clear as I've managed to get. Again, this is on the healthy one and looks quite different to the sick one.