Loaches Online Forum

From time to time I have had dithers develop crooked spines. This usually happens in White Clouds or danios. The fish seem to live a normal life span, but have to live with the crooked spine. I give my fish a varied diet of different types of flakes, mini pellets, and frozen food so I don't think its diet. Right now I have a male Danio choprai with this condition. Its the most aggressive feeder of the bunch and seems otherwise fine.
Any ideas as to why this happens from time to time?

It could be fish tuberculosis. Check this out, http://www.aquarticles.com/articles/man ... ishTB.html One symptom is a crooked spine.

I've read about it from time to time on a Finnish fish forum. It can affect humans too so be careful.

As far as my very inexperienced knowledge goes, I think it's a number of separate factors none of which are likely to be down to your husbandry.

I think that many deformities occur when the fish are still fry and have not had the required vitamins, possibly more so with captive breedings where only one type of food may be fed to promote growth. In the wild deformed fish are probably amongst the first to be predated upon and so don't occur in the numbers that they do in commercial institutions.

The deformity may be genetic or as a result of injury incurred either at the fry stage or once in your tank.

I have had guppies and Danios with crooked spines. However, they never had any of the other symptoms described by the article on fish TB. They lived long lives, fed well, weren't skinny, had no problems with their scales or lesions. They were perfectly normal except terribly bent. And they weren't bent when I got them. That developed the bend as they aged. I had a similar situation to what Jim described. I am also curious about what this is. My other fish were not affected. The two fish were in two different tanks at two different times.

That's what I find unusual. The fish are all appear healthy, other than the spine, and live long lives.

it could be genetics as well like osteoporosis or other bone disease. The body can't absorb nutrients like calcium like it did.

I've noticed it a lot with female guppies toward the end of their lives.

Hello..,

I am by no means an expert on the subject, but given the fact that many fish are bred in captivity, this doesn't surprise me. Orcas kept in captivity develop a "bent over" dorasl fin, but you never seem to see it in the wild. No-one really knows why this is. Even if you look at humans, you see many deformities occuring at any stage of life, from pre-birth to old age. Some of these deformities are easy to pin down and have a direct cause. Others just seem to crop up, with or without pain, and no-one really knows why. In fish such as guppies and danios who have a fairly long history of being bred by humans (especially in their terms, having short life spans), there are probably things going amiss we may not even know about. Not only have we taken them from their natural habitat, but also we have played with their genetic makeup in order to produce the traits that are desirable to us. We see this in dogs, too. Purebreds are by far more likely to end up with health problems than mixed breeds, and we now know this is likely because we have made their gene pool smaller than what it would be in the wild. Yet as an animal lover, I like to believe we have a kinship and a mutually beneficial relationship with the animals we take into our homes and our lives. We can do the best we can to give our pets the longest and healthiest lives possible, but we are still not able to replicate exactly the conditions they would have in nature. This would be my best guess. If it is not a disease, and you have eliminated all other possibilities, I think all you can do is feed and care for these fish the same as you would for all the others.

I think it is great that you are asking why. That is what drives us to find the truth about the things around us. I think in this day and age it is so easy to think it has all been done and not ask questions. But the more I delve into fishkeeping, the more I see that it hasn't all been done, and we are the best people to try to find out the answers to these questions. How far better for someone who loves their subjects to study them.
soul-hugger

I too have noticed my danios will get bent spines in old age. Sometimes it is really crooked and/or early in life, but mostly with my fish it will be a faily mild crook and only starts after I have had them a year or more.

I notcied that my current spawning of male fancy guppies have bent spines, their grand mothers had it before they expired. I have been observing the second generation of spawnings by their sisters and have not noticed this condition (yet). I thought that this was a natural genetic condtion since all of my previous guppies of from the orginal breeding trio appear to have developed bent spines after they reach adulthood. Could this be a genetic condtion that is triggered opon reaching adulthood in some strains of these fish mentioned above?

Joe

Specifically looking at Joe's information:
* Limited Gene Pool (Original breeders)
* Known deformity in the original fish
* Deformity is showing up in some of the second generataion, but not all, yet. (Females might show the problem later?)

Any time you select parents for a certain trait, and have only a limited quantity to select from it is likely that the parents may have some genetic problem, and in line breeding and inbreeding with inadequate culling the problem will get fixed in that breed or color selection almost as firmly as the characteristics of that breed.

If you are looking for dogs with a certain head and eye shape, and you are looking within a certain breed to refine that eye shape you are already starting with closely related dogs (one breed, perhaps relatives that show the trait you are looking for). Then you further reduce your gene pool by selecting only dogs with the right eye shape and you end up with Collie Eye Anomaly.