Ancistrus inheritance

[Suckermouth]

Has anyone bred shortfin Ancistrus that had longfin parents? Sellers seem to think it's important to note that their shortfin Ancistrus had longfin parents. If I'm not mistaken, the long finned trait is dominant in zebra danios and I see absolutely no reason it wouldn't be the case in Ancistrus. That is, if you have two short-finned Ancistrus breed (and both had long-finned parents), then you should still get all short-finned Ancistrus. Can anyone confirm?

EDIT:

I changed this topic to Ancistrus inheritance. I've been writing an article on and off for PlanetCatfish about the inheritance of albinism and long fins, but if anyone has any information on the other common Ancistrus color patterns (calico, false L144) that would be great.

[krazyGeoff]

I have had longfin (F) breed with shortfin (M), and the offspring were a mix of long and shortfin.
-- Edit (I had the M and F around the wrong way)
If the longfin trait was dominant, then this must mean that the parents of my original longfin (F) must have a shortfin in there somewhere?
My longfin (F) cross longfin (M) seem to have all longfin offspring, which would indicate that the Female longfin was a double gene longfin?

Therefore I think that your statement is correct.

Cheers

[Suckermouth]

Hmmm, this doesn't actually 100% confirm my suspicions. Let's assume long fin is recessive.

The first cross would then be this: Ff (short fin F) x ff (long fin M) which would lead to Ff and ff fry (a mix). The second cross would be the long fin M with a long fin F (which would also be ff) yielding all ff fry (long-finned).

The above crosses working assume that the female short-finned parent is heterozygous with a hidden long-finned allele. This is probably unlikely, but it is still possible to get the same results you did. The fact that the parent's genotypes are unknown is the issue. However, I think your completely right, but there are assumptions and then there is solid proof.

So yes, I think what you're saying can support my suspicions that the long fin allele is dominant, but I want to be rock-solid sure. The best proof would be either 1: breeding short-finned fish that both are known to have long-finned parents and finding all short-finned fry or 2: breeding two long-finned fish together and finding you get some short-finned fry (which would only occur with certain long-finned fish that are carrying a short-fin allele).

[sunfish]

krazyGeoffs results are possible with both long-finned dominant and long-finned recessive. Since most people don't think twice about mixing several types of bristlenose it is not uncommon to find crosses between different forms. So a short-finned fish with a long-finned allele should not be that unlikely. Since he found both long- and short-finned offspring at least one of the parents has to be heterozygous.

So yes, I think what you're saying can support my suspicions that the long fin allele is dominant, but I want to be rock-solid sure. The best proof would be either 1: breeding short-finned fish that both are known to have long-finned parents and finding all short-finned fry or 2: breeding two long-finned fish together and finding you get some short-finned fry (which would only occur with certain long-finned fish that are carrying a short-fin allele).

1 only works for F1 intercross with homozygous short and homozygous long parents (i.e. Ff x Ff). However, if long-finned was recessive long x long could not produce short-finned offspring (see 2).
2 would exclude that long-finned is recessive.

[Suckermouth]

1 only works for F1 intercross with homozygous short and homozygous long parents (i.e. Ff x Ff).

You can get Ff fish from another cross, although the cross you describe is the only way to guarantee all fry that are Ff. So it's not the only way it would work, but it would be the best way to do it.

[krazyGeoff]

I have had longfin (F) breed with shortfin (M), and the offspring were a mix of long and shortfin.
--Edit had the M and F around the wrong way

If it helps the short fin (M) from this pairing is a 5th generation from my breeding programme, Currently this females "sisters" are also breeding.
There has never been any long fin babies in about 3,500 fish that have been through the programme.

Statistically I would imagine that there would have been at least 1 longfin offspring if the gene is recesive?

It may also be worth noting that the offspring from the L x S mating all have a much more brilliant colour pattern than any other offspring I have had, with the white seam on the tail occupying about 40% of the tail area, irrespective of the tail length.

I'm not entirely sure what to do with the offspring. Are they "bad fish"?

Cheers

[sunfish]

1 only works for F1 intercross with homozygous short and homozygous long parents (i.e. Ff x Ff).

You can get Ff fish from another cross, although the cross you describe is the only way to guarantee all fry that are Ff. So it's not the only way it would work, but it would be the best way to do it.

If you want to cross Ff with Ff you need to be sure of the parents' genotype. Other mixes will of course also produce a certain portion of Ff offspring. But in this case you'd have to either run a DNA test or else produce several batches of offspring before you can be sure that you really have Ff-fish.

@krazyGeoff
If your short-finned fish are from a stock that does not carry the long fin gene you will never get long-finned fry (not counting the odd spontaneous mutation). If, however, you pair L and S and then use the resulting S for your programme, statistics would indeed 'demand' a certain portion of L offspring, if long-finned was recessive.

I would not be too concerned about you LxS mixes, they're all the same species (or at least the same mix of different species). Just say that they're a mix of long and short and that's fine. Do you have a picture of those? I've never seen common BNs with such a wide seam.

[bronzefry]

I have a short finned male with a long finned female. The offspring are approximately 40% short-finned and 60% long-finned. Very vigorous pair: carpet-o-Ancistrus in a 55 gallon tank.
Amanda

[Suckermouth]

I have had longfin (M) breed with shortfin (F), and the offspring were a mix of long and shortfin.

If it helps the short fin (F) from this pairing is a 5th generation from my breeding programme, Currently this females "sisters" are also breeding.
There has never been any long fin babies in about 3,500 fish that have been through the programme.

Statistically I would imagine that there would have been at least 1 longfin offspring if the gene is recesive?

This does help. It takes as little as two generations of crossing to bring out recessive genes if you do the right crosses. If you see long-finned fry from short-finned from and it was recessive, you would expect 25% of the fry to be long-finned from those particular crosses. This confirms it.

1 only works for F1 intercross with homozygous short and homozygous long parents (i.e. Ff x Ff).

You can get Ff fish from another cross, although the cross you describe is the only way to guarantee all fry that are Ff. So it's not the only way it would work, but it would be the best way to do it.

If you want to cross Ff with Ff you need to be sure of the parents' genotype. Other mixes will of course also produce a certain portion of Ff offspring. But in this case you'd have to either run a DNA test or else produce several batches of offspring before you can be sure that you really have Ff-fish.

True, and true.

It may also be worth noting that the offspring from the L x S mating all have a much more brilliant colour pattern than any other offspring I have had, with the white seam on the tail occupying about 40% of the tail area, irrespective of the tail length.

I'm not entirely sure what to do with the offspring. Are they "bad fish"?

If your short-finned fish are from a stock that does not carry the long fin gene you will never get long-finned fry (not counting the odd spontaneous mutation). If, however, you pair L and S and then use the resulting S for your programme, statistics would indeed 'demand' a certain portion of L offspring, if long-finned was recessive.

I would not be too concerned about you LxS mixes, they're all the same species (or at least the same mix of different species). Just say that they're a mix of long and short and that's fine. Do you have a picture of those? I've never seen common BNs with such a wide seam.

I would also be interested in pictures. In your LxS mixes, do both the short-finned fry and the long-finned fry have the wider seam? Or is it just the short-finned fry with a wider seam?

I have a short finned male with a long finned female. The offspring are approximately 40% short-finned and 60% long-finned. Very vigorous pair: carpet-o-Ancistrus in a 55 gallon tank.
Amanda

The expected frequencies would be 50% long-finned and 50% short-finned. Your short-finned male is homozygous (has two short-finned alleles) and the long-finned female is heterozygous (has a long-finned allele and the hidden recessive short-finned allele).

Thanks all, your information confirms to me that long-fin is a dominant trait. This should go out as a warning to anyone who is purchasing short-finned fish where the seller talks about them having long-finned parents, as it will have no bearing on the fry of the short-finned fish produce. They are probably simply misinformed and are assuming the long-fin trait works like albinism, when it does not.

Anyone know about the inheritance of some of the other Ancistrus traits? I'm thinking piebald, false L144, and such.

[krazyGeoff]

Pictures sure.
Perhaps 40% is, under closer examination a bit of a "fishy story" but nevertheless they are quite impressive to me, and I have never seen seams this wide on an ancustrus.
Short fin:


Long fin:


False L144, I will assume here is the golden form with the black eyes? (My Avitar)

I have one young pair of regular ancistrus that produce from every spawn (approx 60 fry), at least 1 false L144, and at most 2, which does not compute with any mathematical theory I can figure out.

My false L144 (4 or 5 generations) have never produced a normal coloured offspring.

Cheers

[MatsP]

"false L144" is

Ancistrus sp(4)

.

--
Mats

[Suckermouth]

Perhaps 40% is, under closer examination a bit of a "fishy story" but nevertheless they are quite impressive to me, and I have never seen seams this wide on an ancustrus.

Interesting. Those are quite wide. I assume those reduce themselves as the fish grow? Do the parents have a normal fin margin? Do the fry have a normal fin margin after they've grown into adults? If adults do not show the wide fin margin it makes it a littler harder because we don't even know what phenotype the parents have, so we can't guess the genotype. This probably just means you'd need an additional generation of crosses than normal to confirm phenotypes/genotypes and thus the inheritance of this trait.

Do all the fry in the long-fin x short-fin batches have the wider colored fin margins? Or is it only some of them? I'm getting at a ratio here. If you have bred these fish that have the wider colored colored fin margins, is there some sort of ratio that appears in their fry?

False L144, I will assume here is the golden form with the black eyes? (My Avitar)

Yes, that's what I mean when I say false L144, and as Mats says, it is now in our Cat-eLog as Ancistrus sp. (4). From what I can tell, Ancistrus sp. (4) differs from albino Ancistrus cf. cirrhosus in having dark eyes and no light-colored spots, and perhaps a yellower body coloration.

I have one young pair of regular ancistrus that produce from every spawn (approx 60 fry), at least 1 false L144, and at most 2, which does not compute with any mathematical theory I can figure out.

You are correct, this is a very odd ratio. It means that there is more than one thing at work than simple random "Mendelian" inheritance. Unlike our traditional Mendelian inheritance there is another cause to this than dominance or recessiveness.

Where did these regular Ancistrus come from? I suppose if you knew if they had false L144 ancestry you'd have said so. Of course, even if there were false L144 in their "pedigree", it'd be an odd ratio.

However, this is also interesting because it confirms that false L144 is tied to A. cf. cirrhosus somehow. This supports racoll's finding that they are basically indistinguishable at a specific gene he looked at, indicating they're possibly the same species. It also seems to indicate that the entire suite of traits for false L144 may be controlled by a single gene, which is interesting. I would've guessed that false L144 was developed by combining various traits together and then line-breeding, but this does not appear to be the case if you can get it after a single step.

My false L144 (4 or 5 generations) have never produced a normal coloured offspring.

I would not expect the L144 color pattern to be dominant over brown, however these individuals may simply be pure. I am curious of the inheritance if you cross back to the brown fish as well as back to "normal" albino fish, although you mentioned you don't any normal albinos.

Thanks for your information, it's very interesting.

[krazyGeoff]

Interesting. Those are quite wide. I assume those reduce themselves as the fish grow?
Do the fry have a normal fin margin after they've grown into adults?

This is the only batch I have so I will need to follow up this post after they have grown out some more

Do the parents have a normal fin margin?

The longfin parent has NO fin margin, the shortfin has no signifigant margin either.

If adults do not show the wide fin margin it makes it a littler harder because we don't even know what phenotype the parents have, so we can't guess the genotype. This probably just means you'd need an additional generation of crosses than normal to confirm phenotypes/genotypes and thus the inheritance of this trait.

You have just taken one step too far than my basic knowledge.......

Do all the fry in the long-fin x short-fin batches have the wider colored fin margins? Or is it only some of them? I'm getting at a ratio here. If you have bred these fish that have the wider colored colored fin margins, is there some sort of ratio that appears in their fry?

I will get back to you on this one also, and define what I say more specifically, since you are requiring a more academic response, to be of value, rather than an aesthetically motivated response.

Where did these regular Ancistrus come from? I suppose if you knew if they had false L144 ancestry you'd have said so. Of course, even if there were false L144 in their "pedigree", it'd be an odd ratio.

One was from my "true" blood line, and the other was from a recent purchace in order to strengthen my blood line. The new fish was selected for its more regular pattern and more striking white "dot" colour.

However, this is also interesting because it confirms that false L144 is tied to A. cf. cirrhosus somehow. This supports racoll's finding that they are basically indistinguishable at a specific gene he looked at, indicating they're possibly the same species. It also seems to indicate that the entire suite of traits for false L144 may be controlled by a single gene, which is interesting. I would've guessed that false L144 was developed by combining various traits together and then line-breeding, but this does not appear to be the case if you can get it after a single step.
I would not expect the L144 color pattern to be dominant over brown, however these individuals may simply be pure. I am curious of the inheritance if you cross back to the brown fish as well as back to "normal" albino fish, although you mentioned you don't any normal albinos.

Thanks for your information, it's very interesting.

I also think that the false L144 is just a variation of the A. cf. cirrhosus, but I am not a scientist.

Cheers

[MatsP]

There are some interesting differences between false L144 and common bristlenose, tho'. Mainly that they stay smaller - Mark Walters at the CSG conference had a breeding group there, and the biggest ones were only about 3-3.5" TL.

--
Mats

[krazyGeoff]

There are some interesting differences between false L144 and common bristlenose, tho'. Mainly that they stay smaller - Mark Walters at the CSG conference had a breeding group there, and the biggest ones were only about 3-3.5" TL.

--
Mats

I had one that was 6'', it was a monster.

[Mike_Noren]

I also think that the false L144 is just a variation of the A. cf. cirrhosus, but I am not a scientist.

I thought the usual story was that the L144 originates from a single aberrant albino import Ancistrus male (of unknown species) which was cross-bred to common ancistrus females, and the offspring then bred to eachother to bring out the recessive albino trait?

If so, L144 is likely a hybrid Ancistrus sp. x Ancistrs cf. cirrhosus, with most of its genetic material from A. cf cirrhosus (and the mitochondrial genes will be pure A. cf. cirrhosus, as mitochondria are exclusively inherited from the mother). It'd be difficult to separate it from a "pure" cf. cirrhosus.

[Borbi]

Hi,

I thought the usual story was that the L144 originates from a single aberrant albino import Ancistrus male (of unknown species) which was cross-bred to common ancistrus females, and the offspring then bred to eachother to bring out the recessive albino trait?

It was cross-bred with a female from the very same shipment (and therefore most likely the same species). And that, in turn, was not "the" common bristlenose.

What we now see labelled as "L 144" (i.e., the false L 144) is a line-bred variety of the common bristlenose (which opens the question if there is one such thing as "the" common bristlenose or whether there are different, similar looking strains distributed over the world, which I would find more likely) which is not the same species as the original L 144.

Cheers, Sandor

[Mike_Noren]

It was cross-bred with a female from the very same shipment (and therefore most likely the same species). And that, in turn, was not "the" common bristlenose.

That is not the way I've heard it, but I've no reason to doubt you.

In that case these "false" fish would be either later crosses who trace their ancestry to the original albino L144 male, or commons with the same type of albinism but independently derived. Either is perfectly possible.
The main difference would be that "true" L144 would then be genetically distinct from common ancistrus, both wrt nuclear and mitochondrial genes.

[Suckermouth]

Mike, there is the possibility that false L144 have inherited their trait from the true L144. racoll was talking about how he might analyze some nuclear genes in false L144 to see if they differ from A. cf. cirrhosus, now that he's done the mitochondrial gene.

Hypothetically, the false L144 could be independently derived, having a similar mutation as the golden zebra danio, but I'm not sure.

[Mike_Noren]

Mike, there is the possibility that false L144 have inherited their trait from the true L144. racoll was talking about how he might analyze some nuclear genes in false L144 to see if they differ from A. cf. cirrhosus

I'm doubtful that'll work, but it's worth a shot.

Hypothetically, the false L144 could be independently derived

Oh yes. If one ancistrus male can get that particular mutation, so can other.

To be honest, though, I'm uncertain if the exact origin of the mutation is all that interesting. After all, both the true and the false L144 are line-bred cultivars, not found in nature (other than as extremely rare aberrant individuals). It'd be more interesting to find out exactly how it works.

[Suckermouth]

To be honest, though, I'm uncertain if the exact origin of the mutation is all that interesting. After all, both the true and the false L144 are line-bred cultivars, not found in nature (other than as extremely rare aberrant individuals). It'd be more interesting to find out exactly how it works.

The origin of the golden coloration I think is mostly a question about identity. However, I am curious as to how the L144 coloration is inherited, so that goes a little bit with "how it works".

[Jon]

"I'm doubtful that'll work, but it's worth a shot."

I agree. It's not feasible.

[krazyGeoff]

Hi Milton,
I have more information for you.

In the cross spawning there were 115 fry.
75 have long fin
40 have short fin.

It is also worth noting that the short fin are bigger than the long fin. The short fin bodies are about 2.5 times as wide as the long fin.

Cheers

Geoff

[Suckermouth]

Hi Milton,
I have more information for you.

In the cross spawning there were 115 fry.
75 have long fin
40 have short fin.

It is also worth noting that the short fin are bigger than the long fin. The short fin bodies are about 2.5 times as wide as the long fin.

Cheers

Geoff

What were the parents?

[krazyGeoff]

What were the parents?

These are from the original parents in this thread (Although I did have the M and F around the wrong way and have edited the previous posts accordingly)

M = shortfin
F = longfin

The spawn size seems really large to me, especially since the parents were not that old.
The "non fry" were all removed after the fry hatched.
It is worth mentioning that there was another teenager F longfin in this tank, but she never looked gravid, so I didn't think anything of it.

[fatcatfish]

I am living in China have been breeding both red and blue eye both parents are long fins yet repeated my frys are 75% short and 25% long fin, since long fin gene are dominent can it be that at least one of the parent are short fins but have artificailly induce longfin perhaps by radiation. can any members help.

[MatsP]

In the past, research has found that radiation is a poor way to introduce meaningful changes in DNA. Yes, radiation will change DNA, but it's nearly always destroying things rather than "making better" (assuming we believe long fins for example is "better"). Radiation is a bit like using a shot-gun to hit a single target bird in a flock of birds - yes, you may well hit a target, but you'll likely hit several others too. With DNA it's much harder, since we don't even know what gene is involved for long fins.

I'm pretty sure Long fins is a random mutation that is line-bred to "lock it in". It is entirely possible that several mutations are needed, and that the common scenario where people are mixing things will have some of those mutations already, and depending on which ones are present or not present, the results are more variable than you'd expect.

I'm far from convinced that long-fin is actually dominant - I'd have thought that long fin would be more frequent if that was the case, since it only requires one mutation (assuming it is one gene that controls this - which seems to be the case in your fish), rather than that mutation also being cross-bred with it's siblings that have the same mutation.

--
Mats