# Melanoma



## coralbandit

I've been breeding swordtails for about 2 years consistently now.I've managed to mix colors and come up with some beautiful variations including showa and painted.To do this I used standard black crossed with kio and and all the other colors .I've just noticed a lump(tumor) on couple of my younger mostly black ones. I've read and am trying to find more info on the link between cancer and black swords.Shortly after joining forum Navigator Black had mentioned that swords and platies were used in studies of cancer(he was right as usuall).I read a little then but had no real concern.Now I unfortunately have more interest in gathering all info I can.If anyone has genetic info or an interest(I know some of you are really intelligent) in helping me understand how I brought this out and avoid it in future I would appreciate it.Like I said I am reading all info I can find but would dig anyones input.Thanks!The culling will begin and I'm searching for new stock to continue breeding but not carry this gene any farther.


----------



## navigator black

So here is my understanding, but bear in mind I'm a high school teacher, not a doctor.
The black on swordtails and platys is potentially cancerous. My understanding is there are genetic mechanisms protecting the fish, but if you hybridize species, you break the defences in a large number of the fry, and malignant melanoma appears.
This has been useful for cancer research, as their melanoma is close enough to ours to be of value in studies.
However, the fish in stores are useless for studies, as domestic swordtails, platys and variatus are not species. They are all crosses with each other, and therefore have lost much of their natural defence system. They are aquarist-produced hybrids made for colour, shape and size- classic mutts.

Researchers work with species from the wild,. Some lines of platys have been maintained and bred since the 1930s, and their genome is mapped to the nth degree. The species of Xiphorus that are studied (there are many) are natural, non hybridized ones. See: Xiphophorus Genetic Stock Center : Texas State University

In the 1970s, black swords arrived big time, and a lot of mine died young from tumours. They vanished from the market, and only occasionally re-appear where I live. I believe from what I've been told (but not read) that cancer rates are high in recent mutts.
I keep Xiphophorus of several species - always separate, always well labelled and not hybridized. These are fish that never meet in nature, and have evolved largely in isolation from each other, although where they overlap, there is some natural crossing. 
If you look at my gallery, you'll see some natural sword species.


----------



## coralbandit

Thanks for the link(and homework assignment).I had read that TSU was doing major research on several other sites.Many sites suggest that using blacks with clear or colored(other than black) fins was one way to avoid the tumors.Other sites say this is hit&miss.I have found lumps on fish with semi clear/yellow fins along with the few that have black in fins (or tail).Unfortunatey I have also found lumps on a few that were half black(looked like fancy female guppy) and one half black half red(really cool looking fish,color divides fish in half).Most suggestions say use male of black berlin type which ironically is the male now set in breeding tank with orange and kio females.I had never noticed the lumps before(I pay pretty close attention to all my fish{nerd I know}) but feel that regardless of color of fish I use now that in mixing previous parents that a black finned must have survived(without tumors) and has left me with fish of various colors carrying the gene.UV light was said to be a contributor and although I offer advice on lighting to others when I feel I have info I am not sure if my LEDs(every tank but one{the other is corallife CFL}) is introducing UV.Possibly the I didn't understand that info completely as TSU said I think they use UV to detect the tumors/or gene.This seems(is to me rather) complicated.I appreciate your info and am still in search of more info and am willing(hoping for) anyones opinions(fact based or not) as this is still ongoing research(TSU hopes to be able to pre-dispose people possilbly with info they're gathering) to this gray area.I will continue to breed(more selectively) and unfortunately know I need to cull affected fish.The affected fish don't equall2% of my fry stock and fortunately the showa line seems clean(which is the line I'm after as they're listed as newest and most sought after variation of swords at the moment) beside being the most beautiful swords I've seen! THANKS!


----------



## Brian757

Here is a link regarding your black swordtails. It is from Ohio University. You might not find much more than school studies being that it isn't a human threat. But for fishkeepers, it means a great deal. Wish you the best of luck with your studies!

OHIO: Research | Fish cancer gene linked to pigment pattern that attracts mates

This is an extremely interesting study and I think its somewhat up your alley. Enjoy!


----------



## coralbandit

The article is encouraging to me believe it or not.The showa line of swords is white/orange(from kio swords) with black spots.Knowing that females are attracted to the spots means that given a choice my females (of any color) will be attracted to and prefer my male showa in my 180g.He was my first that "I created" by mixing and origanally thought he was unique and labeled him "calico"(photo in my gallery). Oddly enough his black has changed over time getting less solid and more spotty.I now have well over40 fry with different black orange white coloring. I really dig them! THANKS for link!


----------



## navigator black

Really interesting.
I may be a wild-type purist whoi will probably never breed for a look, but I still find this stuff quite interesting. Thanks for the link - it was a good read.


----------



## coralbandit

TWO TYPES OF MELANOMAS IN A NEW EXPERIMENTAL SYSTEM OF PLATYFISHSWORDTAIL HYBRIDS - WAKAMATSU - 2008 - Development, Growth & Differentiation - Wiley Online Library
this link says there are two types of melanoma ;fry and adult. In it they say the fry has tendancy towards regression.Does that mean it could go away?I've found nothing else saying anything similiar.On a side note another poster has camallanus which brought up Levamisol and upon searching info on drhttp://en.wikipedia.org/wiki/Levamisole one of it's uses,although listed as infrequently used was melanoma.


----------



## navigator black

It never stops eh? I love the way what we think is a simple question has a way of leading us in all kinds of directions. The we follow them and find more directions.
I never could be satisfied with just looking at a fish or fishtank. You miss too many good questions if you take things as they are without digging a little...

I have now learned a little about regression in Melanoma - interesting stuff. I started out looking for a definition and ended up reading some intriguing stuff.


----------



## coralbandit

So as I mentioned I was going to start culling the infected fish I had discovered.I only have discovered 10 so far, 5 of which are highly pigmented with only 1 very hard to notice tumor(very small).I don't feel the smartest when I read these articles and do my best to understand something I never learned about at all,but thought that maybe I should hold on to the darkest least affected as they're not contagous or behaving sickly at this point.If they live long enough I'll see if the tumors get worse /indifferent/or regress.I also figure there is a chance they're sterile so I don't need to seperate right now or soon as they're young.Also E mailed inkmaker to pick his brain today on levamisole.I haven't heard back yet but will keep everyone updated.Nature is odd and possibly that's what makes it so interesting sometimes.Without failure success does not taste so sweet, nor are we challenged.I'm still digging and will share what I find.


----------



## coralbandit

communicated with Charles who said he is aware of levamisole being used in colon cancer treatment.He said pharmacalogical reports indicated levamisole during second and third stage.Also said improved immune resistance and helped body fight the cancer was reported.Niether he or I know proper dosing for this application but he is willing to supply and I told him I can't hold him responsible for any trial I attempt.He believes dosing to be less than used for camallanus(13.3ppm) so I asked him to figure out what I would need in 20g and contact me again.Since this is "unexplored territory" due dilligance ,close observation and consistency is the approach I will take .More to come as this could take sometime, but possibly some"good" could be had out of a otherwise seemingly hopeless situation.


----------



## navigator black

Just to play the devil's advocate - since it is a genetically based cancer, do you want to treat it and carry it forward in your breeding stock? Levamisole won't affect the DNA, to my knowledge.
Would it not be likely to express itself even more in the next generation?


----------



## coralbandit

No plans to breed any of the fry.Possibly making true observation more blurred if fry tumors could regress as prior article said, but interested to see if has any effect on existing diposition.I will not breed any that have any signs what so ever.I culled all that I recognised yesterday,decided to keep none.Knowing swordtails retention of sperm I expect more.I'm more interested in preventing than curing.I have seperated all black males from black females, as I believe(since this just showed) that the black to black was the cause.Possibly(first thought, haven't had a lot of time to really weigh) levamisole introduced to parents(have healthy black fry) prior to breed would yield no tumors?I'm not sure of what to do,but have unique oppurtunity to "research" myself.I would,will never pass less than 100% healthy fish to anyone.I actually brought infected fish to LFS to show as owner had never even heard of this before. I appreciate your thoughts, I value your opinion tremendously.No sick fish leaves my house any way except toilet.Actually even expressed concerns to owner over the possibility anyone who purchased black(berlin{has good amount of orange}) lost their fish(as he said that customers really like them) and offered replacement with healthy fish.He said he had no returns.


----------



## navigator black

I know you well enough that I never thought you'd sell them - i was thinking more of the longterm viability of your strains. I guess I'm used to my wild-type lines that no one wants!
What would worry me is that if you suppress the expression of the tumours by treating for them, you might have a lot of breeders carrying the lethal genetics. At least this plague on swordtails kills a lot of the fish carrying it.
That thing in the articles (for anyone reading who didn't read the links - it appears that females in strains heavily affected by cancer shun males with cancer, but those in lightly affected populations prefer males with 'nice' skin cancer patterns) made me ponder the problem. If the cancer is not expressed (but is there) and since we know there doesn't seem to be an environmental trigger, would it tend to run wild in the genes of the strain?
I could easily be talking total garbage - it's just an interesting problem. I had a cancer problem with wild-type Rio Otapa/Veracruz swordtails. There was melanoma all over my Otapas and I gave up on them. They died off fairly young, and the survivors were left to live out there lives with only basic attention.
However, the young I didn't realize I was saving (java moss) are all clean so far. If that holds (and they are in the danger age now) then the carnage served a positive role...


----------



## coralbandit

as you said ,I didn't understand 4-6 months ago(no signs of cancer visable) and still true to this day;3 out of 4 of the fry that die in my fry / grow out tanks are black.The disease has some control over whether it continues or not.The biology student at my LFS says that it is common in all animals for female to prefer male of better color as a sign of virillity.He quickly pointed out fancy guppies and made mention of peacocks and the attraction that the female has to male she feels(triggered by nature and desire to propogate)to choose what she sees as the best(healthier )choice.I found interesting in the Ohio study although they concluded that 2 out 3 females were attracted to the spotted male , that the third(I believe they said healthy{clean})did not. We both know if you think you can predict the behavior of nature in extreme cicumstances you surely soon to be suprised.This is truely an interesting learning experience for me I would not have chosen,but(not to sound ill) am enjoying.This an oppurtunity that can't be purchased or easily brewed up. Do I wish this was not the topic we discuss? Of course, I strive for healthy ,desirable fish,but this is not all that bad as 8 or 10 out my present population of 300-400 is reasonable to me (without personal attachment{they're not my dogs}).I also feel the cost of obtaining any pet should be no where near the cost of keeping if cicumstances require.I have no clue about levamisole(or what it will cost{still waiting to hear back from Charles}) or if it will make a difference or how I'll apply it, but if it is a legit option with ;yours,Charles and any other input I can get I'll try to do something positive instead of nothing.I dig watching my fish, but can't leave it at that either.That's why I breed to have a vested interest and a sense of pride.If the toilet comment (in previous post) offended anyone who is reading this crazy thread I got to tell you the name of the game;QUALITY,NOT QUANITY.I live my life by that, I run my business on that.(period)


----------



## navigator black

Understood. I'm not sure I would be able to resist trying either. It is unfortunate, but it is really interesting at the same time.
I don't know know your background, but I have no laboratory training or skills in the research field. 
I think the kind of curiosity a serious aquarist can get into is probably not unlike what Doctor Myron Gordon had when he first realized he could use his livebearer hobby to learn about melanoma. I figure as long as we harm no one, there's nothing we shouldn't try to learn as much about as we can. I hope you'll keep this thread coming back as you learn more, so I can be an info-parasite on something intriguing.


----------



## navigator black

IU Simon Cancer Center - Levamisole

Levamisole | Definition and Patient Education

Interesting stuff, but hard to project onto how it would affect fish. Dosing seems a worry, and there were a few references to immune suppression - that a patient taking the drug would be less able to fight off a virus or another pathogen. I'd assume it to be the same for fish.

it also seems to be used as part of a drug cocktail, so it might not be very effective against fish melanoma on its own. Then again, I'm just a nerd with the internet...

There's only one way to find out.


----------



## coralbandit

So it would appear that the levamisole is not used on its own, but rather in addition to chemo, or 5 flouro.This seems a stretch for fish.To answer you back a few post, my background is not one of scientifc academia.I took earth science in 1979 and was not required to have any further science credit to graduate.I'm not required(nor have I ever been) to do research of any kind.I own my own business(copper craftsman/custom furniture/high quality builder),hardly a Dr./or lab type person.I aquire knowledge on topics that interest me and can be fairly thorough.Possibly my best approach is just in selective breeding and monitoring.I have not heard back from Charles(I imagine he is digging) and possibly quicker than I on the thought that drugs may not be the answer to this situation.I have culled all the infected fish that I recognised,but wait for more.About keeping my lines healthy I think I brought this out by letting black to black(they were already 4-6 generations deep) continue to breed without proper planning.As mentioned before black males and females are seperated not to breed amongst themselves again(for quite a while as I see it now.)The mixing of the colors to have multi- colored is really my goal(along with not producing infected fish).On that note While showing my LFS the infected fish I saw there first ever shipment of what they called "tri color swords".The coloring was nice(mine are better) and the over all health of those fish was questionable at best(and I told them both of my thoughts) and said they'll see in a few months.I believe I brought this out but have to believe it was there anyways.This has made me wonder;why swords or platies? What about black mollies,multi colored gold fish,or any of the other (stealing your phrase as seems appropiate)mutts?No other fish besides swords and platies?


----------



## navigator black

I have lost other fish to cancer or tumours, but it has been very rare. I have the advantage of my hard to believe (to me) 46 years keeping fish. I have seen a lot, as I have lurked pet stores and wholesalers the whole time. 

The only family with serious reports of melanoma are Xiphophorus. Right now, it seems a lot of the research I stumble across is on X. malinche and especially X cortezi, two really pretty wild-types that domestic breeders don't work with. They seem as prone to cancer as maculatus and helleri. 

When I say I stumble, I'm like you (I think). I like reading scientific pdfs on things concerning fish, but my last science course was Grade 10 Biology. I am a reader, and this kind of thing interests me. Swordtail group melanoma is something I learned about a long time ago, so if I see something on it, I read it and try to decipher the jargon.

I'm surprised I've never seen reference to cancer on Gambusia, given their spotting, but they are a different tribe of livebearers, genetically. The same for my beloved Mollies. I have kept marble mollies off and on since I was eight years old, and have never lost one to cancer. I saw my first cancer on a black sword within a few months of buying my first group of four, and have seen it on lots of mutts, and on wild helleri.
I have wild-type X montezumae into their sixth or seventh generation here. I have usually got buckets of them - I have to use them as feeders to keep them from overpopulating their tanks. And with them, I have never seen a tumour, in spite of lots of black pigment. the same is true of my wild platy types, X evelynae. I have never seen a tumour there, in spite of lots of black spotting.


----------



## coralbandit

Have heard back from Charles and he explained (briefly)about "proper "dosing and the theory behind any attempt I may make.I am ordering some levamisole,although not 100% locked into how I will(or if even) administer it.More research needs to done and a set "long term" treatment plan implemented with a few fish in isolation to accurately be able to verify any results.More to come in near future,when I figure out my attack.


----------



## Cat696

Bottom line is simple. (though heart breaking).. You are dealing with a recessive gene.. you will never know that the combo that you use for breeding is faulty till it is too late, all you can do is work with the probabilities.. 
You are an intelligent and resourceful man, I have no doubts that you will produce beautiful and healthy stock when all is said and done.. you are too observant.. 
Good Luck!!


----------



## coralbandit

So it's been like 3 months since this topic has been discussed.I did receive levamisole from Charles but never used it as I'm not thinking I'm going to cure an infected fish.Unfortunately any fish with this issue is culled with ice cubes and water.
The good news is with seperation of black females from black males I have virtually eliminated the melanoma.It truely is caused by an over abundance of the black pigmentation in this fish.
I still find it odd that only swordtails are subject to such ailments,but nature is often unexplainable.
While allowing my swords to do as they wanted I had a totall of maybe 20 fry that were infected with melanoma.Some were really covered with tumors some with only 1 or two.Now if I even find one of my blacks with a little tumor it is extremely rare,as I haven't seen one in more than a month.
So I'll hope that seperating the male and female blacks is sucessful.
I still use both male and female blacks , but with opposite colored mates.My 29g is where I place all black females and they have a pineaplle and kio male to breed with(great mixes come from them).I keep 1 male black with 7 orange and a kio female in my 20 long.He is the meanest male sword I've ever seen and will not tolerate 1 other male at all(I've tried with as many as 5 to distribute the beatings,but he rules).
I can keep my mixed (black and a good amount of orange) together without issue.
So this may be the last post on this topic unless something unforseen pops up.The whole issue came from to much pigmentation and seems to be resolved.


----------

