F0 F1 f2 ......

[Bissot_J]

i just got a figth with a friend
and want your advice

me i say :

2 wild fish who have baby : the parent teke name F0
2 F0 give F1 Baby
2 F1 give F2 baby

am i wrong ?

and if i mix ie : 1 male Wild and 1 female F100
the result is nothing ......

am i wrong ?

Jason

 

[Neil]

Bissot_J,
That's pretty much the way I understand it! Offspring from wild fish are F1. Offspring from F1 fish are F2. I think that F0, however, is a pretty useless term. Wild fish are wild or WC (wild-caught) and F1, F2, etc. are tank-bred or CR (captive-raised).
I am not quite sure how it works out with 1 WC and 1 CR fish though. I suspect that offspring from a wild and F1 would probably have to be considered an F2, although it should be an F1.5 .
Neil

 

[jvr]

F ?

That is the way it seems to be every where in the fish hobby except for cichlid fanciers.
I was let to believe that among cichlid keepers F0 stands for the first generation produced from wild fish, every other fishkeeper that are non-cichlid people refer to first generation from wild fish as F1.

Correct me if I have been misled.

Thanks
John

 

[tjudy]

Genetics 101



The 'F' is F1 stands for the genetics term 'filial', and it describes a generation in a line breeding experiment. There is no (sa far as I know) F0 in genetics. Any cross that starts a line breeding sequence is a P-cross (parent cross). The offspring of that cross is the 'first filial' generation...F1. When two siblings from that generation are bred together, that is called the F1 cross. An F1 cross produces an F2 generation.

The aquarium hobby has taken this system and changed it a bit. I have always used the F0 to mean wild fish. I describe a wild pair as as F0 pair. Their offspring are often described as F1...which is an accurate label. If a pair of siblings from that F1 are bred, they produce what is called F2... also accurate.

Here is where we get inaccurate... If I buy an F1 male from Bob, and an F1 female from Pete, and then manage to spawn them, then in the HOBBY the offspring are called F2. However, by genetics standards they are F1... 8O

Would that really be a problem? I do not think so. The line is really not and inbred line. Would it be dishonest to describe them as the offspring of 'wild' fish? YES!!!!! The selective pressures in the wild do not exist in a fishroom. The fish you buy that are wild are the survivors of some pretty intense experiences. The fish that are raised in captivity do not get 'culled' other than for obvious body shape deformities. I would describe the offspring of unrelated F1 fish as "the offspring of unrelated F1 fish".... :wink: .... what I would NOT call them is F2... :? ... because they are not really linebred (nicer term than inbred) fish.

 

[aspen]

great description ted. thanks for that! here's a q for you. is a wild fish 'better' genetically, than a tank bred fish, and if so, why? what we are 'gaining' are pretty colours, but what are we losing, when we tank breed fish? any thoughts?

rick

 

[tjudy]

I do not necessarily think that wild fish are 'better'. I think that wild fish gene pools are the result of a set of selection pressures that are not the same as fishroom pressures. Natural selection is an extremely complex process.

Here is an interesting scenario that might illustrate my point. Let's say that a wild fish carries a gene that makes that fish a little slower than its siblings, but only when it is a juvinile. There is probably a greater chance that it will be taken out of the gene pool before it reaches adult size if it is in the wild... but not a definite chance! That fish could survive. That gene, however, has absolutely no importance in a predator-free fishroom. Should we be worried that a 'little bit slower' gene is perpetuated? I do not think so... I also think along the same lines as wildlife biologists, however, that captive bred lines of organisms should never be released into the wild (except in situations where species recovery is at stake; and only then if recovery is assured.)

I personally do not have problems with the selective breeding of fish for specific color varieties, so long as:

1) The hobbyist is anal retentive about being honest about what is produced (no trying to claim a flower-horn is not a hybrid).
2) A new 'strain' is not named as a strain until it breeds true for at least two generations (meaning less than 10% 'sports' in a spawn.... this would eliminate most of the rapid expansion in discus strains).

I ask this question? Do we need to try to improve upon wild fish? Do we really have a right to be critical of selective breeding? There is some definite allure to that side of the hobby. Anyone who wants to work towards more red in a cockatoides or Aulunocara has every right to do so. I personally like to play that game with platy-sword hybrids.

 

[Nermal]

I must say Ted, I like your analysis of captive raised vs. wild raised.

It seems that many hobbyists think that selective breeding in captivity, for color or to produce hybrids, is perfectly acceptable. Others think vthat such actions are deplorable and species should not be hybridized or selectively bred based on hobbyist desires. Still others are disturbed that generations of fish are linebred (inbred?) although no selection for particular chacteristics are made.

I agree, there are many, many, many, many selective factors that occur in a natural environment that do not occur within the aquarium. Conversely, there are selection factors that occur in the aquarium that are not present in nature, and not necessarily a part of any willful selection on our (tobbyist) behalf.

Captive populations are so small they are subject to genetic bottlenecks and genetic drift. Both are problems that are recognized but impossible to prevent, although there are steps that can be taken to slow or minimize these factors.

This is a good subject for our Cichlid Conservation Working Group forum.

 

[firefly]

P1= wilds in this case
off spring = F1
Fry from off spring =F2
HTH

 

[Discus Man]

and if i mix ie : 1 male Wild and 1 female F100
the result is nothing ......

Neil and Ted never gave a direct answer to this point, but in my experience, a domestic parent and a wild parent offspring were called F1.

The domestic parent obviously can't be (or very unlikely) genetically related to the W.C. fish so generation 1 has been called F1. F1, 2 etc. was used to show how many generations removed from W.C. they had become.

So am I wong?

P.S. never sold any using the F terms yet, so don't worry!

 

[tjudy]

Hey I can post today!!! (I hate my ISP)....

Hey Discus Man...

From a genetics (the science of) view, a wild parent to a captive raised parent would create F1, because the parents at totally unrelated.

In the hobby I think most would say one generation lower than whatever the captive raised parent is. If it is F1, then most hobbyists would call the fry F2.

I would let buyers know it is an outcross to wild stock....