Bad genetics??? recessive disease??? this is rearing it's ugly head again, so far only in one original group of fish

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Magnum Man

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Jun 21, 2023
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Southern MN
so I've had a group of the yellow Axelrodi Rainbow fish, since I restarted my tanks almost 2 years ago now... I had bad water, to start with, later an outbreak of Ich, but most seemed to succumb to a strange disease, & I've posted pictures before... I started with 3-4 of them originally... the tank its in, has gone from pretty bad, to where it's starting to come around... what ever the others had, did not seem contagious, but they wasted away, the muscles around their spines seemed to shrink, & they deformed over time... I have one left in the that tank, & I noticed the 1st signs of deformation, that the others displayed before they passed, so I'm thinking I'm going to put this last one down... they had been in a tank with a couple other varieties of rainbows, one of which did not survive the Ich outbreak, but the Madagascar's that have been in that tank are starting to look fabulous ( I lost one male during the Ich outbreak, but one male & 2 females remain ), & since I have added a few of the blue & orange, juveniles, but those also look good... I know they had begun breeding these in Asia, & the yellows were purchased from a seller I no longer buy from, but that purchases a lot of Asian bred fish... it starts with dark coloration along the spine on both sides, & almost looks like bruising... and slowly the muscles start to shrink up???

this is one of the couple threads I started on these guys...

this is something that can turn a nice normal looking fish, to look like the one in the picture in the linked thread, over the course of 3-5 months... fortunately it doesn't seem to be contagious??? the tread I linked, was posted in Oct. of 2023, & the newly effected fish, survived Ich, since then, & is just now starting to show the 1st signs...

there seems to be quite a few assorted "bent spine" threads, on this forum... I'm wondering what we are really dealing with here???
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This is the last fish from this original group... I'm hoping if I put it down, that will be the end of this... but it would be nice to know what the issue is...
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Pictures of the fish?

Since this has happened before, I would find a fish vet and take the live fish to them to be necropsied.
will try to get a picture of this fish tonight ( less deformed than the one in the linked picture ) since I have no local contact here, I'm wondering if it could be frozen???
I could freeze it, & send it here... looks like it would cost me almost $100.00

Looks like refrigeration is better than freezing...

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Yeah possibly $100, maybe more if they send it off for further testing. That part kind of concerns me if they send it off for more testing. But something like that would be a good start and should tell you why it happened.
It sure sounds like "wasting disease." I had a large clown loach with it. i was able to cure it using Flubendazole. I moves the fish from it's 150 gal into a 20L to treat it. Fortunately it had not yet stopped eating. I gave it one round of the flubendazole. rested it and did a big water change and then did a round of Praziquantel (this was likely not needed). Then again rested it and repeated the flubendazole.

By that time it seemed to have started to gain weight. So I spent another few weeks power feeding all kinds of good food- Froaen bloods and brine shrimp, Repashy mixes of Spawn & Grow and Soilent Green or Bottom Scratcher and Soilent Green (both an 80%/20% mixture).

I chose to use Flubendazole because of this article:

Eradicating Hydra and Other Pests with Flubendazole
From: Journal of the American Killifish Association September/October 2003
Vol.36, No. 5
By Charles Harrison, Ph.D.

The hydra-killing Flubendazole that I used in my office aquarium to eradicate hydra led me to a larger realization. The “wasting” fish in that tank seemed to become cured when I added Flubendazole to the water. Whoa! This was quite a remarkable revelation. My intent was to remove the hydra and any possible nematodes and, to my surprise, the disease I have found to be associated with a particular protozoan species was cured.
You can buy Flubendazole from Dr. Harrison here:
I'm going to come in with my usual Eeyore view of things. You have Melanotaenia herbertaxelrodi. The hobby stock from the farms is reported to be rotten with tb. I bred mine as soon as I got them and was able to get fry that grew up clean and lived well. But the adults I bought were dead from tb within months. I would have lost the fish if I hadn't bred them and used a UV sterilizer as they hatched.

I've seen tb sores in stores, on herbertaxelrodi, blues, dwarfs and a few of the rarer ones.

Symptoms? Wasting. Eventual rectangular sores, not open, on the flanks.

If they weren't rainbows, I wouldn't suggest this. It isn't as much of an issue with other groups of fish. I used to keep a dozen species of rainbows, and am now down to two because of the frustrations caused by what this sneaky disease does to them.

I hope it was something else. But they are rainbows...

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