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KrazyNoobs
08-16-2012, 10:19 PM
I have searched the internet for all the information I could grab on Discus Fish genetics, and there isn't too much information.

I have two pairs of discus, one of those pairs are spawning.

The first pair is a 15cm Blue Diamond Discus male and a 13cm Wild Brown Discus (F1, parents were wild caught) female, and they have layed eggs in a community tank before, the Blue Diamond Discus fertilizing them. The main problem was that my Angelfish, Tetras, and Ram Cichlids always would sneak past the two discus parents and eat all the eggs.

I decided to move the pair from the 500 litre (125 gallon) 2ft tall, 18" deep, 6ft wide (60cm*45cm*180cm) tank that was heavily planted to a bare-bottom 216 litre tank (2ft*2ft*2ft OR 60cm*60cm*60cm) that was empty. I purchased the tank to house the breeding pair.

10 days later, (today) I finally have eggs. The two parents are protecting the eggs pretty well, but this time around, the male DID NOT fertilize them, so I expect all of them to be white in 24 hours, and all gone in another 12.

When they first started shaking around each other a few days ago, I became interested in what the fry will look like. I decided to look up some information on Discus Genetics. There IS NOT enough information on the internet, but there is plenty to predict the colours of the Discus Fish. (A Blue Diamond Body [recessive] * a Wild Brown Body [dominant, i think. Please correct me if I'm wrong] would make the fry 100% Wild Brown in appearance, although their genotype would be a heterozygous Wild Brown with recessive Blue Diamond)

I continued to proceed to other species to learn more about genetics, and I read about the Pea Plants, where there are multiple chromosomes that impact different characteristics, such as Flowers, Height, etc.

I want to know in which ways the same thing applies to Symphysodon (Discus Fish) species, and what different chromosomes impact what different characteristics? (is body colour one chromosome, is fin colour/tail colour another, how about eye colour, and stripes?).

My second pair always stay together, but they haven't shown any interest in spawning. I am expecting them to start soon, so I set up another 216 litre 2ft*2ft*2ft tank for them. One is a Red Leopard Discus Male, and the other is a Cobalt Female. I cannot decipher all the complicated talk about Leopard Discus, and what occurs with their genetics. Any ideas on the outcomes for this pair?

Also, what would happen with an intermediate of two recessive genes, such as the recessive Blue Diamond and a recessive Golden? What would be the hybrid between the two? Would it be an intermediate (both traits are evident, showing Blue Diamond AND Golden on the same fish), or would it just be one or the other? Would it be colourless?

I am also designing a program in Visual Basic 6.0 to estimate the outcome of a cross between Discus Fish species, but I need lots of information first, so answering the question about the recessive/recessive would help alot, but most importantly, the chromosome question's answer would be information that I crucially need. Thanks!

Rod
08-18-2012, 03:33 AM
Hi KrazyNoobs,

Welcome to simplydiscus

That is some first post and i'm not going to attempt to answer it all. But i'll have a go at a couple of points.

BD x brown will not produce more browns. They will be brown based, but i think you will find a lot of variation in the blue color. The blue color is controlled by multiple genes and as such does not operate under simple mendalian genetics (monogenic inheritance). Otherwise your assumptions are correct, they will be wild base color blue turquoise variations carrying the BD recessive gene.

Concerning your leopard x cobalt pair. They will produce turquoise type discus. Neither have any monogenic mutations and both types are produced purely by selection. They will probably be really colorful discus, though highly variable.

2 recessives are commonly found on the same discus, albino blue diamond is a good example. They are carried completely independantly of each other.

HTH

Rod

KrazyNoobs
08-19-2012, 07:54 PM
Thanks for the information, Rod!

About the eggs with the Blue Diamond and Wild Brown, as predicted, they weren't fertilized, and they turned white, and all fluffed up and died. :(

On the other hand, the Red Leopard Discus was fought off by a Blue Calico Discus, and now the Cobalt female is with the Blue Calico. (The Blue Calico is a standard Calico Discus with a whitish-bluish body and pure blue fins. Also, a yellow tail is slightly evident)

This pair is exactly what I have been hoping for, as the Blue Calico Discus is one of the most beautiful Discus Fish I have ever seen (I will probably add pics later). I hope this doesn't take too much of your time, but what would occur with this cross (assuming the Blue Calico has an intermediate between a Blue Diamond Body and a White Body)?

The only issue with the pair is that the Blue Calico is a bit young (9 - 10 months). He is approximately 7.5cm (3"), and the Cobalt Female is well over two years (11cm, 4.5").

Also, would anything interesting happen if my Cobalt Discus (mine has 5 vertical dark-purple stripes, red on the tip of its top fin and a yellow tail) bred with a standard Calico Discus?

If anyone would at least give me an idea of the genetics of a Calico Discus, that would be excellent! I hope I'm not asking too much!

Also, are there any good sources for information on Discus Genetics? (such as books, articles, etc.)

Thanks!

Rod
08-20-2012, 05:12 AM
I'm not sure what a blue calico is? It sounds like a variety of ghost discus, and unfortunely i have no useful experience with them. I don't know how the gene is carried. It sounds like a great cross, i'd love to see the resulting fry.

As far as genetic information on discus is concerned, there is nothing that i know of that is really useful. What information we do know, is from hobbiests experimenting and making deductions using Mendel's law of segregation.

Rod

KrazyNoobs
08-20-2012, 04:45 PM
Thank you very much for the information!

Later, I will attach some pics of my pairs.