Black Ram Genetics?

My LFS recently got 5 Black Rams in stock. By the time I got there only one was left. I've got a gentics question. I have a mated pair of regular GBRs at the moment. My assumption is that the "black" gene is recessive. What are the odds/percentage that some of spawn would be black if I introduced some more of the mature regular GBR "fry" ( few months old now ) with this new black Ram? The black Ram is a female.

I ask because I would like to attempt breeding these black Rams as I have several tanks dedicated to breeding regular GBRs. Just curious if someone with a biology background or breeding experience has insight into the genetics.

 

Can't help with the specific situation because I know zilch about ram genes.

But in terms of genetics; if it is a simple one-locus case, and you are correct about black being recessive, then breeding a regular ram with a black rams will result in 100% regular coloured rams, all of which will carry the black gene.
Then when you breed one of those carriers to another black ram, 50% of their fry will come out black, the other 50% will be normally coloured but also be a carrier of the black gene. Breeding any of these carriers to a black will result in 50% black offspring, 50% regular offspring that are black carriers.
If you breed two regularly coloured rams that are both carriers of black, 25% of the offspring will be black, 50% will be regular coloured and carry black, and the last 25% will be regular coloured and not carry black at all.

This is all presuming that the regulars you start out with don't themselves already carry black (which, if they are unrelated to your blacks, is likely).

 

Can't help with the specific situation because I know zilch about ram genes.

But in terms of genetics; if it is a simple one-locus case, and you are correct about black being recessive, then breeding a regular ram with a black rams will result in 100% regular coloured rams, all of which will carry the black gene.
Then when you breed one of those carriers to another black ram, 50% of their fry will come out black, the other 50% will be normally coloured but also be a carrier of the black gene. Breeding any of these carriers to a black will result in 50% black offspring, 50% regular offspring that are black carriers.
If you breed two regularly coloured rams that are both carriers of black, 25% of the offspring will be black, 50% will be regular coloured and carry black, and the last 25% will be regular coloured and not carry black at all.

This is all presuming that the regulars you start out with don't themselves already carry black (which, if they are unrelated to your blacks, is likely).

This was exactly what I as looking for. Thanks a ton for the detailed reply!

 

I know nothing about genetics ,but think you got good info there . What you should be trying for is the dark blacks ..
Here is my two cents on getting dark blacks ..


Again I know nothing but breed fish , these fish in particular .
My understanding of how to get darks is very similar to I think what they call 'Double Dark ' black angels .
You will see many rams that look like the one you pictured and like your GBRs [that look very nice ] from spawns . You want to look for the darkest and work them .
The pictured fish is the result of breeding black rams in my fish room since 2017 ..Took me all this time ! Got my first darks [and golds] back on 9/11/17 almost 6-8 months after getting my first black rams ..I got my stock directly from the creator of the black ram Shahar Danzinger in Israel as he imports to some shops in the US..I got my blacks at discus madness in NJ..

 

Actually, in most fish black is a dominant or partially dominant gene, and given that there are a lot of "blackish" Rams out there, I suspect the same is true for this species. It appears to be partially dominant with the normal gene, just like Angelfish. However, in Angelfish it is completely dominant over other color genes, such as Gold. I've observed that certain genes tend to be inherited the same way regardless of species, so I believe that a solid black Ram might also be able to carry a hidden Gold gene. Simple test for this would be to match a Black Ram with a Gold Ram and see how the fry turn out.

If the above turns out to be true, the first question becomes how many pairs of genes are involved in producing the dark black Rams. The second question is how much does environment affect the amount of dark pigment on an individual.

At this time, no one has done any rigorous controlled testing to find out the answer to either of those questions. I don't know of anyone who has the necessary understanding of controlled breeding to accomplish this type of testing at this time. It is more than just knowing how to breed the species. It requires careful selective breeding and a lot of data tracking. People just don't "have the time" to do that stuff any more. Environmental manipulation is a bit easier, but gets expensive to provide the variations necessary.

 

Actually, in most fish black is a dominant or partially dominant gene, and given that there are a lot of "blackish" Rams out there, I suspect the same is true for this species. It appears to be partially dominant with the normal gene, just like Angelfish. However, in Angelfish it is completely dominant over other color genes, such as Gold. I've observed that certain genes tend to be inherited the same way regardless of species, so I believe that a solid black Ram might also be able to carry a hidden Gold gene. Simple test for this would be to match a Black Ram with a Gold Ram and see how the fry turn out.

If the above turns out to be true, the first question becomes how many pairs of genes are involved in producing the dark black Rams. The second question is how much does environment affect the amount of dark pigment on an individual.

At this time, no one has done any rigorous controlled testing to find out the answer to either of those questions. I don't know of anyone who has the necessary understanding of controlled breeding to accomplish this type of testing at this time. It is more than just knowing how to breed the species. It requires careful selective breeding and a lot of data tracking. People just don't "have the time" to do that stuff any more. Environmental manipulation is a bit easier, but gets expensive to provide the variations necessary.

First thank you for the reply !
When I got my darks from DM in 2017 I had many fry that were not dark .But on 9/11/17 I had a batch that only I think 7 fry survived from .
5 were very dark and I a call them still today my F1s and they had 2 other siblings that were gold .
When I asked my known fish head what happened he said the g old is used as a blank slate by breeders particularly in Israel .
Since them I now have gold rams ! Never had them before but I have more then enough now .All from the parents of my F1s.
I try to match dark to dark but Marco who perfected the black ram to the Dark knight ram has mentioned that breeding dark to gold gets 50/50 with only 50% of the fish carrying the dark gene..
I still think there is a double dark but as mentioned and not kidding clueless !
Reading on DD angels says initially they were much smaller and slower growing which is certainly the case with black/dark rams ..
When I breed fish like this I humbled and know how lucky I am ..

 

I know nothing about genetics ,but think you got good info there . What you should be trying for is the dark blacks ..
Here is my two cents on getting dark blacks ..


Again I know nothing but breed fish , these fish in particular .
My understanding of how to get darks is very similar to I think what they call 'Double Dark ' black angels .
You will see many rams that look like the one you pictured and like your GBRs [that look very nice ] from spawns . You want to look for the darkest and work them .
The pictured fish is the result of breeding black rams in my fish room since 2017 ..Took me all this time ! Got my first darks [and golds] back on 9/11/17 almost 6-8 months after getting my first black rams ..I got my stock directly from the creator of the black ram Shahar Danzinger in Israel as he imports to some shops in the US..I got my blacks at discus madness in NJ..

This explains quite allot of what I've found and read so far. Online, they appear as this, but during the rare occasion I find one at a LFS, they look as mine pictured above. This is quite impressive. Congratulations, that is a stunning fish. I'm up for the challenge, but I'm going to consider looking for better stock as well. Thanks for this info!

Approximately how much do one of these "double dark" ones run? For my mediocre stock it was still $50. Did you start out with something similar to mine and achieve what you have above?

Actually, in most fish black is a dominant or partially dominant gene, and given that there are a lot of "blackish" Rams out there, I suspect the same is true for this species. It appears to be partially dominant with the normal gene, just like Angelfish. However, in Angelfish it is completely dominant over other color genes, such as Gold. I've observed that certain genes tend to be inherited the same way regardless of species, so I believe that a solid black Ram might also be able to carry a hidden Gold gene. Simple test for this would be to match a Black Ram with a Gold Ram and see how the fry turn out.

If the above turns out to be true, the first question becomes how many pairs of genes are involved in producing the dark black Rams. The second question is how much does environment affect the amount of dark pigment on an individual.

At this time, no one has done any rigorous controlled testing to find out the answer to either of those questions. I don't know of anyone who has the necessary understanding of controlled breeding to accomplish this type of testing at this time. It is more than just knowing how to breed the species. It requires careful selective breeding and a lot of data tracking. People just don't "have the time" to do that stuff any more. Environmental manipulation is a bit easier, but gets expensive to provide the variations necessary.

Very interesting. Thanks for the reply, black being partially dominant does make more sense as I read others replies. I might pick up a gold ram and test how the fry come out.

 

This explains quite allot of what I've found and read so far. Online, they appear as this, but during the rare occasion I find one at a LFS, they look as mine pictured above. This is quite impressive. Congratulations, that is a stunning fish. I'm up for the challenge, but I'm going to consider looking for better stock as well. Thanks for this info!

Approximately how much do one of these "double dark" ones run? For my mediocre stock it was still $50. Did you start out with something similar to mine and achieve what you have above?

Not sure who else even has them or is breeding them in country ..
I'll add all my golds come from black so may carry the /a black gene even ? I sure don't know but now have a LOT of golds !
Your a few post short of PM or buy sell part of this forum

 

So idk anything about ram genetics except that some 'rules' of angelfish genetics serum to apply to rams as well, I've thought about it many times.

So a platinum angel has two gold genes and two blue genes. It's a opalescent white fish with iridescent blue fins. Apparently a ram with gold and electric blue genes results in a iridescent white ram equal to the look of a platinum angel. I've also seen discus like this.

So with angelfish, one dark gene will result in a slightly darker angelfish with black fins called a black lace. Two dark genes makes the fish jet back, so dark that you can't see the black bars without a flashlight. An angelfish with one gold gene and one dark gene is called hybrid black, and is just as black as a double dark, but a little more matte black.

Double Dark angelfish are harder to breed, they are not as genetically healthy. I assume the same applies to rams because DD rams are difficult and not very long lived atm.

So going by the info we do have about angelfish, and assuming it applies to rams as well, i'd try to work with gold x black (D/g in the color locus). Just saying what i'd do.

 

This is a quote from the creator of Dark Knight Rams, Marco Du Toit: “
Dark Knights breed true.

I get asked about this frequently and have even been called a liar. ‍♂
So I want to try and show some differences in breeding outcome.
This is very basic genetics so it should not really be contentious.

In the photos you will be able to see a pair of Electric Blue Rams with their 10 day old fry. Even at this young age you can see that there is a difference in colour amongst the fry. This is because both the parents carry genes for both Electric - as well as Powder Blue.
The fry ratio is simply expressing the genetics of the parents.
Because the Golden gene is recessive, the "Powder blue" gene is "dominated", and so the parents look like real Electric blue. (phenotype)

Then some photos of "Dark Knights" with different coloured fry. Again these are phenotypically Dark knight, but with mixed genes.
These parent fish are a 1st generation cross between a Golden and Dark knight. Again the Golden gene is "dominated" by the Dark Knight gene, and so the parents look like Dark Knight, but their offspring expose the mix in their genes. You can see some light as well as dark coloured fry

Then there is the pair of "true" Dark Knights. (Genotype)
From this pair you can see all the fry are Dark Knight. Once adult these fry will also breed absolutely, 100% true.

So, if you have a solid black Ram pair and they do not breed true, it does not mean that Dark knights do not breed true, it simply means you do not have a pure, genotype Dark knight.”

It really is no different than if you had electric blue/blue cross and it was more electric blue than a regular blue Ram, but when you breed them they obviously don’t come out pure electric blue.

 

So my suppositions were correct. Good to know, plus I learned something about Powder/Electric Blues!

 

HI Guy25

Here is a thread on another forum that may help you as well.

Separate from the thread, one of our local club members picked up six black rams in Vancouver, BC about and year ago and has bred them. They are not very prolific, with small numbers of eggs laid compared to regular blue rams. Many of the eggs seem to be infertile. And of the survivors about 25% are black rams, the remainder are light colored. I don't believe they are 'albino' per se but almost that color of pigment, it appears that the 'black' / 'dark' gene is recessive.

 

HI Guy25

Here is a thread on another forum that may help you as well.

Separate from the thread, one of our local club members picked up six black rams in Vancouver, BC about and year ago and has bred them. They are not very prolific, with small numbers of eggs laid compared to regular blue rams. Many of the eggs seem to be infertile. And of the survivors about 25% are black rams, the remainder are light colored. I don't believe they are 'albino' per se but almost that color of pigment, it appears that the 'black' / 'dark' gene is recessive.

Those rams look familiar ?

 

coralbandit

lol! same fish different user names. I had to go to a different user name on this site; it would not allow seattle_aquarist as a user name.

 

coralbandit

lol! same fish different user names. I had to go to a different user name on this site; it would not allow seattle_aquarist as a user name.

I was inferring that I sent those rams to Amy ! That is how I recognize them ..My picture and purple towel..Those are the F1 parents of most of my dark black fry ..
They were not in breather bags but may have taken 8 days to arrive to her as she documents ..