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Hi All. Just hade a batch of fry off my bristlenoses and i have three distinct colours. Normal brown, Albino with pink eyes(normal) and an interesting orange colour with black eyes. The brood is probably a three way split between the colours. The parents are brother/sister from a brown albino cross. Do you think the fry (6 weeks old) will retain this orange colour and is this a common occurance ( colour wise). The photos are the best i could get , sorry.
Thanks Dave

I believe the "orange" colour is what we call Calico in the Cat-eLog, but I'm not sure.

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Mats

I think Mats is right on that, although in South Yorkshire it also seems to be referred to as "black and red" variety; I was of the opinion that that was a different genetically fixed trait rather than a "half albino" phenotype, but I could be wrong. I'd have expected 3/4 black, 1/4 albino, although a second possibility exists that there's a recessive calico gene carried by your brown fish.

My original male was quite pale when young, then turned very dark later on- he's more of a midnight olive green than black or brown now. We've had a few posts over the last year in terms of people reporting bristlenose colours (I don't mean albinos) changing over time- I've a first generation pair with a black male and very pale female- their offspring came out of the cave as the majority being very pale, but with some black fish, and then most of the fry changed to black, although a couple are still pinky-orange. I've had a few strange experiences with bristlenose changing their colour over time, even sometimes changing when over a year old.

Obviously your albinos will stay as albino, and I assume the "black" fish will stay as brown (or at least not change to albinos), but it will be interesting to see if the middle-coloured fish change.

I'm pretty sure the albino trait and the brown trait are behaving just like the Mendaliev diagram would predict: 25% albino, 75% normal. That's certainly what I get when my fish breed and give off albino. What is likely the scenario here is that the parents are also part Callico form, as well as part Albino.

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Mats

Thanks for that Mats- that was the "second possibility" I referred to, but I misinterpreted your original post- sorry.

Hmmm, what are the exact numbers of fry of each color?

I don't know much about the calico color form, but it's allele is not necessarily the same locus as albinism.

MatsP wrote:I'm pretty sure the albino trait and the brown trait are behaving just like the Mendaliev diagram would predict: 25% albino, 75% normal. That's certainly what I get when my fish breed and give off albino. What is likely the scenario here is that the parents are also part Callico form, as well as part Albino.

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Mats

As a small note, Gregor Mendel bred peas, and Mendeleev made the periodic table. Two different guys. ;)

Sorry for the name mixup. And yes, I'm 100% sure that the genetics behind the Calico and the Albino form are different in different positions, and that it's likely that the parents have had both genes in some past.

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Mats

So can i assume that the orange fry are likley to be calico. If the calico came from a recessive gene from one or both of the parents what would be the likley outcome from crossing the orange (calico)fry back to each other (brother/ sister).
Thanks Dave

MatsP wrote:Sorry for the name mixup. And yes, I'm 100% sure that the genetics behind the Calico and the Albino form are different in different positions, and that it's likely that the parents have had both genes in some past.

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Mats

Indeed. Assuming calico is recessive (a safe assumption if both are brown) and assuming the fish were both heterozygous at both loci, we would expect a 9:3:3:1 ratio. The 9 would be brown, 3 would be albino, 3 would be calico, and 1 would be "albino and calico". This makes a little more sense in traits that don't interact like albinism and calico probably do (epistasis); biology classes usually use wrinkles and pea color as an example. My guess is if the albinism gene is homozygous, you get albinism regardless of the state of the calico, which would result in a phenotype ratio of 9:4:3. In any case, brown would still be the majority of the young. It's possible that calico works differently.

baldyman wrote:So can i assume that the orange fry are likley to be calico. If the calico came from a recessive gene from one or both of the parents what would be the likley outcome from crossing the orange (calico)fry back to each other (brother/ sister).
Thanks Dave

IF calico is a recessive gene as predicted and ignoring albinism, then you will get no calico fry crossing with a fish that is pure for brown, 50% if they were backcrossed with a fry that is brown and "carrying" the recessive calico gene, and 100% if they were crossed with a calico fry. The presence of albinism actually complicates this, but without doing all the crosses (there are are many several genotype possibilities among the brood) on punnett squares, you would get fewer calico and more albino young then I gave above, which assumed no albinism in the genes.

The orange ones sure look like Calicos. Albino as well as Calico are recessive. So both parents have a copy of each gene (= are heterozygous). The fry should roughly be 50% brown and 25% albino and calico (To be exact: 9/16 brown, 3/16 calico or albino and 1/16 calico + albino).

The brown ones can be "just" brown, but most also carry albino and/or calico. Crossing those will give you only brown fry or brown, albino and/or calico fry, depending on their genotype.

The calico ones are homozygous for calico, and the albino ones for albino. 25% of the albinos will also be calicos, but I really don't know whether they look different to "normal" albinos.

Crossing two of the albinos will give you 100% albinos (with possibly 25% of them calicos).

Crossing two of the calicos will either give you 100% calico or 75% calico and 25% albino(calico), depending on whether both parents carry albino.

Thanks everyone for all the replies. First time i have had bristlenoses spawn . I know they are supposed to be easy. But to have a bonus mixture like this is very pleasing. Are the Calico bristlenoses more expensive to buy than the brown or albino , or do they all tend to go for the same price?
Thanks again Dave

Prices on different colour fish depends on the customer... Some people pay a lot to get something "special", others don't. When I sold some at an auction, two similar size males, one brown and one albino, the brown went for about half again what the albino did. But I've also seen shops where the albino or 3x the price of the brown ones.

I'd say calico are "more" like the normal ones, so more likely to be "same price".

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Mats

wow, you're lucky to get three colours! awesome! Around here the calico and albino would go for more money then the browns. Silly, huh? Same fish. Although I had so many batches of BN fry I cannot even count them and no calico or albino. So go figure.