I have a F3 brood of midevil came from a local breeder. Is F3 brood weak? Or genetically inferior compare to f1 and f2? Any thoughts?
Is F3 (filial generation 3) weak brood?
- Thread starter Rakeboy
- Start date
There is no general answer to this, as many different factors play a role.
The first thing to ask is what you consider weak.
That can be different things. Such as the susceptibility to diseases, aggressiveness, deformities, but also the body shape.
An F3 may not be able to flee from predators as quickly as an f0, but a well selected F3 may even be better suited for the aquarium than an f0, as they are better adapted to the germ load in the aquarium and can be less aggressive.
E.g. the M. beanie available here are almost all f9 or f10, but they are significantly better to keep in the aquarium than either f0 or f1. And you won't see any difference in appearance since they come from a well-established conservation program.
But there are also examples in the other direction. Like Copadichromis borleyi. Most breeders have always selected the most colorful males for breeding. In a group with several males, the most aggressive specimen is always colored the most. After just a few generations, the fish became significantly more aggressive.
So it depends on the breeder how much an f3 differs from an f0 and if that is something desirable or not.
The first thing to ask is what you consider weak.
That can be different things. Such as the susceptibility to diseases, aggressiveness, deformities, but also the body shape.
An F3 may not be able to flee from predators as quickly as an f0, but a well selected F3 may even be better suited for the aquarium than an f0, as they are better adapted to the germ load in the aquarium and can be less aggressive.
E.g. the M. beanie available here are almost all f9 or f10, but they are significantly better to keep in the aquarium than either f0 or f1. And you won't see any difference in appearance since they come from a well-established conservation program.
But there are also examples in the other direction. Like Copadichromis borleyi. Most breeders have always selected the most colorful males for breeding. In a group with several males, the most aggressive specimen is always colored the most. After just a few generations, the fish became significantly more aggressive.
So it depends on the breeder how much an f3 differs from an f0 and if that is something desirable or not.
Most of your available hobby fish are F3 or greater. BTW anything after F2 is denoted as "captive bred". Like any other animal the more you continually inbreed the same stock the greater the likelihood of recessive genes expressing themselves. These recessive genes could code for deleterious aspects but could also code for different coloration like albino or melanistic for example. The best way to avoid "inbreeding" captive bred fish would be to obtain captive bred from different sources. I have no qualms about buying captive bred (F3 or greater) fish as long as they have not been hybridized. I prefer fish that come with a collection site notation but that's just from keeping killifish for years.
Are You say F3 midevils. Meaning you have the 3rd generation of the cross. And your fishes great grandparents. Are 1 devil and 1 Midas. F1 was the first cross Which is your fishes grand parents and f2 within the cross is your fishes parents.and then your F3s.
You should still be showing some
Vigor from the initial cross assuming any selections at all were made. If no election criteria was applied to breeders and weakmfish were selected or allowed to breed that can cause you problems. And by F3 assuming true F3 where it’s true down line breeding of fillial generations- you will start seeing or noticing a lot of reccssive stuff that was buried- and plenty of those traits can be problematic- but they can also be more easily discarded because they are showing up rather than being masked or buried by dominate traits that are being docsrded.
in a closed gene pool once a dominant trait is gone, it’s gone and there is a continual slow ide toward the recessive traits
an example. I have 2 sibling pairs of fish that are F3 or F4 I also have a sibling of there’s that I discarded from
My breeding program because he has a slightly short caudal peduncle. He’s a short body ever so slightly.
if I include him there a good chance that the fry will look for the most part ok- but the next generation of sibling pairs would those a high percentage of that short body. TheF3s/4s that don’t show the short peduncle proably
Don’t carry it either- and more down line selection will indeed eliminate that trait from
My “line”
We use the “filial generation” designation inappropriately frequently. Or at least partially so.
If I have 2 wild pairs of fish that are “unrelated” from the same
Collection local there offspring will each be F1 as they are the first filial generation from that broodstock. If I then cross fry from each spawn I have another F1 generation because it’s the first filial generation from that “new” parent stock. But they are the second domestic or captive bred generation. So F2 from wild as we say. The true F2 would be the second generation down the line from 1 of those pairs.
Or…
beeeding F2 from 1 pair to F2 from another pair of the same species same local would be an outcross to a different “strain” within the species and local- it won’t create F3 because it contains a cross of 2 original parent stocks.
The important thing for you is to be highly selective down line when you breed. And also to pull any fish that don’t fit your standard now so they aren’t allowed to pair off and become your breeding stock.
You should still be showing some
Vigor from the initial cross assuming any selections at all were made. If no election criteria was applied to breeders and weakmfish were selected or allowed to breed that can cause you problems. And by F3 assuming true F3 where it’s true down line breeding of fillial generations- you will start seeing or noticing a lot of reccssive stuff that was buried- and plenty of those traits can be problematic- but they can also be more easily discarded because they are showing up rather than being masked or buried by dominate traits that are being docsrded.
in a closed gene pool once a dominant trait is gone, it’s gone and there is a continual slow ide toward the recessive traits
an example. I have 2 sibling pairs of fish that are F3 or F4 I also have a sibling of there’s that I discarded from
My breeding program because he has a slightly short caudal peduncle. He’s a short body ever so slightly.
if I include him there a good chance that the fry will look for the most part ok- but the next generation of sibling pairs would those a high percentage of that short body. TheF3s/4s that don’t show the short peduncle proably
Don’t carry it either- and more down line selection will indeed eliminate that trait from
My “line”
We use the “filial generation” designation inappropriately frequently. Or at least partially so.
If I have 2 wild pairs of fish that are “unrelated” from the same
Collection local there offspring will each be F1 as they are the first filial generation from that broodstock. If I then cross fry from each spawn I have another F1 generation because it’s the first filial generation from that “new” parent stock. But they are the second domestic or captive bred generation. So F2 from wild as we say. The true F2 would be the second generation down the line from 1 of those pairs.
Or…
beeeding F2 from 1 pair to F2 from another pair of the same species same local would be an outcross to a different “strain” within the species and local- it won’t create F3 because it contains a cross of 2 original parent stocks.
The important thing for you is to be highly selective down line when you breed. And also to pull any fish that don’t fit your standard now so they aren’t allowed to pair off and become your breeding stock.
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Anything after f3 is annotated as captive bred by Kevin at TUIC…. Not the hobby at large and not the academics. Also see the difference between F3 and “3rd domesticated generation or captive bred generation”
annanimals filial generation truly is not a measure of
How long it’s family has been domesticated- tho they do have a correlation
I’ve also reduced it to sibling pairs/ when that’s not truly appropriate either.
the original parent stock could consist of a group of fish, frommwhich collectively the fry they produce are F1 and when bred together produce F2 tho they may not be sibling pairs- it’s a closed gene pool based on a selected set of parent stock. Whether that be a single pair or a group of individuals- whose progeny them become the 1st filial generation
This is why we apply The term to “from wild” as the only selection criteria for parent stock is that it was t captive bred. So when we talk about “F3- whatever” crommwild what we are implying is that they are ina filial line- but reality is- 2 unrelatedF4s from unrelated parent stock from the same local will not make F5s, but they will make the 5the domesticated generation- but it should be healthier than it’s F4 parent stock due to the reintroduction of genes cast off as result of selection pressure in each line.
the original parent stock could consist of a group of fish, frommwhich collectively the fry they produce are F1 and when bred together produce F2 tho they may not be sibling pairs- it’s a closed gene pool based on a selected set of parent stock. Whether that be a single pair or a group of individuals- whose progeny them become the 1st filial generation
This is why we apply The term to “from wild” as the only selection criteria for parent stock is that it was t captive bred. So when we talk about “F3- whatever” crommwild what we are implying is that they are ina filial line- but reality is- 2 unrelatedF4s from unrelated parent stock from the same local will not make F5s, but they will make the 5the domesticated generation- but it should be healthier than it’s F4 parent stock due to the reintroduction of genes cast off as result of selection pressure in each line.
Gonna disagree on this one. Aquarium hobby, especially specialized breeders (i.e. killifish, exotics) anything after the 2nd filial generation is most usually termed captive bred or tank raised. No serious breeder is going to care about anything after F2; quite frankly most are interested in obtained either wild specimens or F1.
Again- filial generations have nothing to do with captive generations. You obtain F1 fry rom rusty. I obtain f1 fry from Ken. We exchange F2 fry. When I breed those F2s from different together it does not make F3. It makes F1. But it also makes the 3rd captive generation.
this mattera for a variety of reasons, for instance-
If you are choosing personal stock, do you want “F2” or do you want a second captive generation derived from 2 unrelated fish? Do you want F3 or do you want the result of an unrelated f1 to f2 paring? Which will still be the 3d captive bred generation.
Now “serious hobbiest” can throw around what we jargon they like- but it doesn’t make it so, and it doesn’t make any of us any smarter.
this mattera for a variety of reasons, for instance-
If you are choosing personal stock, do you want “F2” or do you want a second captive generation derived from 2 unrelated fish? Do you want F3 or do you want the result of an unrelated f1 to f2 paring? Which will still be the 3d captive bred generation.
Now “serious hobbiest” can throw around what we jargon they like- but it doesn’t make it so, and it doesn’t make any of us any smarter.
I think we are talking about two different things in different ways.
" If you are choosing personal stock, do you want “F2” or do you want a second captive generation derived from 2 unrelated fish? Do you want F3 or do you want the result of an unrelated f1 to f2 paring? Which will still be the 3d captive bred generation."
"The best way to avoid "inbreeding" captive bred fish would be to obtain captive bred from different sources."
" If you are choosing personal stock, do you want “F2” or do you want a second captive generation derived from 2 unrelated fish? Do you want F3 or do you want the result of an unrelated f1 to f2 paring? Which will still be the 3d captive bred generation."
"The best way to avoid "inbreeding" captive bred fish would be to obtain captive bred from different sources."
I assume they are midevil since i cannot determined whether this fish was wild caught. Nevertheless, i just wonder on this topic because of the weak f3 i had with flowerhorn cichlids. I thought that this inbreeding may also be applicable with midevil.