Why hasn't anyone bred a smaller goldfish?

[THE V]

Runts are often stunted due to an accumulation of deleterious genes. A great and simpler example of this is black angelfish. If you incross two homozygous fish you'll get 100% homozygous fish which is great for the market but they grow very slow and it takes longer to get them to market. If you do a heterozygous x heterozygous cross you get 1/2 het blacks that grow well, 1/4 homo blacks that grow slow but are still marketable at the small size and 1/4 gold which is a nice fish in itself.

Same thing happens in goldfish. With the Philadelphia Veil-tail if you select to strongly on double anal fins you loose the length in the tail. If the tails grow to fast they can swamp slow growing fish and they just get weak and die.

If you push a strain to hard on a trait especially small size you're going to crash a line.

You can't sell tiny fish, people want a certain size fish (~2inches) but they just don't want it to get 8 inches. If a runt strain takes 3x the time to reach market as a normal fish no one is going to pay the extra $$$ for a goldfish that stays small.

Market size of 2"... If you develop a new breed, change the market. i.e. charge a premium for them. Say a normal goldfish at 2" you can sell at $1, a goldfish for smaller tanks at 1" you can start out at $10-25. Advertise as a breed that is perfect for smaller aquariums. It will live 15+ years in a 20 gallon. It's called creating a niche. Those who do it first successfully get the highest profit of course it also involves the highest risk and you might lose your shorts on it.

You seem not to be able to understand that overall adult size does not necessarily have to be from negative genes. When you are breeding for other traits they do pop up and can lead to smaller sizes. Size gene are usually QTL's with complex inheritance. These are often unpublished because of the difficulty and population specificity to them.. You seem to have practical experience in raising/breeding fish but not a strong understanding of genetics. You write about line breeding, this is a very commonly used technique because it is simple but often has disastrous results. There are other ways to breed but are usually slower and take more expertise. Population shift techniques would probably be best in this instance. Basically the goal is to shift the population to a smaller size while still maintaining enough diversity to overcome deleterious genes.

Large fish are frequently kept in aquariums but it is not a wise thing to do regardless of the apparent "success" of keeping the fish alive. Single tail Goldfish can get very large although it is possible to find runts that would fit in a 180. But how can you be sure in a reasonable time frame?

All fish we keep in aquariums survive in much larger bodies of water in the wild. In keeping them inside tanks we just have to be sure to offer them the best possible environment. 180 properly cared for is more than large enough to house 10-12 single tailed goldfish. The key phrase of course is properly cared for.

 

[Ichthius]

Hi V

I am not geneticist but I work in the field. You seem to have an understanding of genetics but not a strong understanding of breeding goldfish and developing lines. In theory, theory and practice are the same in practice they are not.

If you look at the glofish your statements about changing the market do not hold water. What was a very expensive fish is now selling for just a bit more than a standard fish. There is not way you're going to develop a market for small goldfish that actually makes money. I've seen way to many trends to know this for a fact.

Who in their right mind would market a fish that lives longer, the entire aquarium industry is based on replacing fish killed due to miss information and outrageous claims.

Making a transgenic danio is much simpler than breeding a specific goldfish as their genetics are not nearly as simple a a diploid organism. A friend of mine works with sticklebacks doing QTL work and when they looked at goldfish they quickly looked the other way.

If you think you can QTL your way into a small healthy breed you must not have work with many strains of goldfish. Go ahead and prove me wrong, not with rhetoric but rather with a small strain. I'll even buy your first fish for $100. After that your market will drop significantly.

By the way how many lines of goldfish are you breeding? Which ones? You to seem to know a lot about genetics but most people into genetics get really frustrated with goldfish because they rarely do what you expect. It's a genome duplication thing I guess.

Best fishes
David
www.goldfishgarage.com

 

[Notophthalmus]

Advertise as a breed that is perfect for smaller aquariums. It will live 15+ years in a 20 gallon. It's called creating a niche. Those who do it first successfully get the highest profit of course it also involves the highest risk and you might lose your shorts on it.

This of of course assumes there is a customer base out there who knows ordinary goldfish are not suitable for a 20 gallon..

 

[AquatiCreations]

Not the same species...the ancestor of goldfish is the gibbel carp, not the common carp. A much smaller fish, but still pretty hefty.

Of Course they are not the same species, My point being that Goldfish are carp,and carp are big.

 

[THE V]

Hi V

I am not geneticist but I work in the field. You seem to have an understanding of genetics but not a strong understanding of breeding goldfish and developing lines. In theory, theory and practice are the same in practice they are not.

If you look at the glofish your statements about changing the market do not hold water. What was a very expensive fish is now selling for just a bit more than a standard fish. There is not way you're going to develop a market for small goldfish that actually makes money. I've seen way to many trends to know this for a fact.

Who in their right mind would market a fish that lives longer, the entire aquarium industry is based on replacing fish killed due to miss information and outrageous claims.

Making a transgenic danio is much simpler than breeding a specific goldfish as their genetics are not nearly as simple a a diploid organism. A friend of mine works with sticklebacks doing QTL work and when they looked at goldfish they quickly looked the other way.

If you think you can QTL your way into a small healthy breed you must not have work with many strains of goldfish. Go ahead and prove me wrong, not with rhetoric but rather with a small strain. I'll even buy your first fish for $100. After that your market will drop significantly.

By the way how many lines of goldfish are you breeding? Which ones? You to seem to know a lot about genetics but most people into genetics get really frustrated with goldfish because they rarely do what you expect. It's a genome duplication thing I guess.

I never said it would be easy, just possible. Large populations (2-3,000 fish) and most of my lifetime to make it there. BTW Molecular Geneticist always shy away from the more diverse species. The math involved with a higher number of genes is enough to give anyone a headache. Sheesh... Drosophila, Danio, and Arabidopsis were all chosen as model species because of short generation time and small genomes.

As for market change, these can happen very slowly or incredibly fast depending upon the environment. For something like this to work, a major campaign of education would be required or choosing a market that is better educated. Italy comes to mind, having banned goldfish bowls.

BTW Goldfish is the hobby... vegetable crop breeding is the profession. Working on my Master or maybe Ph.D (still up in the air at this point) in breeding right now. I've got a final on Wednesday I should be studying for.

I work with crops that drive the molecular guys nuts as well. I know the genetics of several species and the particular challenges unique to each (watermelons suck). The more you know about this kind of stuff the more complex it gets. Goldfish are just one of the more fun ones.

 

[THE V]

Of Course they are not the same species, My point being that Goldfish are carp,and carp are big.

A Chihuahua is a dog and St Bernard's get big, therefore a Chihuahua will get big?

 

[J double R]

A Chihuahua is a dog and St Bernard's get big, therefore a Chihuahua will get big?

that comparison is moot.

chihuahua is a TYPE of dog. st bernard is a TYPE of dog.

carp is a TYPE of fish.

thus.. st bernard is a st bernard.. they are big.

carp are carp. they are big.

not all dogs are big... and not all fish are big, but some types of both are.

 

[Notophthalmus]

Actually V didn't go far enough. Chihuahuas and St. Bernards are varieties of the same species. Goldfish/gibbel carp are one species within the carp group (Family Cyprinidae, Subfamily Cyprininae), koi/common carp are another. These fish have very different sizes in nature. Common carp are frequently 50 pounds or more, while gibbel carp are seldom more than a tenth that size.

 

[J double R]

Actually V didn't go far enough. Chihuahuas and St. Bernards are varieties of the same species. Goldfish/gibbel carp are one species within the carp group (Family Cyprinidae, Subfamily Cyprininae), koi/common carp are another. These fish have very different sizes in nature. Common carp are frequently 50 pounds or more, while gibbel carp are seldom more than a tenth that size.

my point exactly. i just wanted to argue semantics for a minute and had a good opportunity.

 

[THE V]

:lol: now that's a cop out if I ever saw one. :laugh: