Does Interbreeding Fish With Offspring Do The Same As Humans?

[Peter C]

If a fry grew up and mated with its mum / dad would the fry be ok or would they be deformed or have problems?

 

[Alm0stAwesome]

Apparently you shouldn't let brothers and sisters cross but mother/son and father/daughter is OK.

It feels SO wrong typing that

 

[wirralbull]

probably not the 1st fewf generations but the more inbred they become the bigger the risk of genetic problems

 

[justin85]

Apparently you shouldn't let brothers and sisters cross but mother/son and father/daughter is OK.

It feels SO wrong typing that

Feels just as wrong reading it to be honest lol

 

[MBOU]

Look at guppies/platies/mollies/blue and gold rams.... for that matter... pretty much *anything* that has colour variations...

Breeders will often use 'line breeding' in breeding a son/daughter back to a parent, sometimes this is necessary to creat colours because two copies of one gene (one from each parents) if the genes are co dominant or recessive.... might not create off spring that are visual for the colour you are aiming for... so breeding offspring back to a parent means that the offspring from that second paring will produce (hopefully) about 75% chance of the colour you are looking for....

A responsible breeder will then 'outcross' to a completely unrelated fish to strengthen the line again...

Not to be undertaken by just anyone if you dont know the genetics of your fish... but then again... look at how many people just let their fish breed themselves to death... *shrugs*

Yes, inbreeding does cause a lot of genetic problems, curved/kinked spines, deformed faces, bug eyes, loss of colour... compromised immune systems, hereditary diseases that might not have been symptomatic had the fish not had 2 copies of the 'bad' genes...

 

[Moby-Krib]

^^spot on info above

In Africans its somewhat common to breed wild caught to the F1 or F2 (first generation , 2nd generation). offspring while line breeding.
Once it reaches F3 (now considered tank bred) most will get a fresh stock to mix in. (outcrossing)
Never goes too deep though as problems do arise.

cichlid_breeding

 

[fish48]

Look at guppies/platies/mollies/blue and gold rams.... for that matter... pretty much *anything* that has colour variations...

Breeders will often use 'line breeding' in breeding a son/daughter back to a parent, sometimes this is necessary to creat colours because two copies of one gene (one from each parents) if the genes are co dominant or recessive.... might not create off spring that are visual for the colour you are aiming for... so breeding offspring back to a parent means that the offspring from that second paring will produce (hopefully) about 75% chance of the colour you are looking for....

A responsible breeder will then 'outcross' to a completely unrelated fish to strengthen the line again...

Not to be undertaken by just anyone if you dont know the genetics of your fish... but then again... look at how many people just let their fish breed themselves to death... *shrugs*

Yes, inbreeding does cause a lot of genetic problems, curved/kinked spines, deformed faces, bug eyes, loss of colour... compromised immune systems, hereditary diseases that might not have been symptomatic had the fish not had 2 copies of the 'bad' genes...

inbreeding does not cause a lot of genetic problems all of the above simptons can and are often coursed by incorrect Temp- water quality and incorrect feeding there are also many other reasons why these simptons may accrue.

 

[Akasha72]

I had brother and sister platies that bred. All the fry were deformed and had to be euthanised - NOT a nice job.

My advice would be not to do it and I personally never would. It's just too risky and too upsetting to see deformed fry and to have to 'deal' with the fry aswell ...

 

[minnnt]

Most fish are cross bred, at the end of the day when most fish keepers buy fish they get a group or a pair. The same fish in a tank at the LFS will more than likely be siblings. A pair of cichlids for instance or a group of Platies, etc. I have never experienced any deformaties and I reckon 99% of the fish I have bred would have been brothers and sisters.

 

[fish48]

I had brother and sister platies that bred. All the fry were deformed and had to be euthanised - NOT a nice job.

My advice would be not to do it and I personally never would. It's just too risky and too upsetting to see deformed fry and to have to 'deal' with the fry aswell ...

so they were all deformed it don't mean it's to do with inbreeding My advice is if you or any one inbreeds there fish is to understand what you are doing and how you are looking after your fish.

 

[TwoTankAmin]

Genetics is not a simple topic. If some of what has been written above is indeed correct, please explain this:

In the 1920s, the American biologist Dr. Myron Gordon and German biologists Haussler and Kosswig independently discovered that hybrids of a particular strain of the platyfish, Xiphophorus maculatus, and the swordtail, Xiphophorus helleri, developed cancers virtually identical to malignant melanomas in man. They traced the origin of these tumors to pigment cells of a platyfish color pattern consisting of black spots on the dorsal fin. Genetic studies demonstrated that melanomas developed only in hybrids that had replaced both copies of a platyfish regulatory gene with swordtail forms that could not control proliferation of the platyfish pigment cells. This animal model was one of the first to prove that some cancers were inherited diseases; after 65 years, these fish still are used in cancer research in the United States, Germany, Canada and Japan.

Dr. Gordon realized that to precisely identify the genes responsible for development of cancer, scientists would require genetically identical platyfish and swordtails for research. Therefore, in 1939, he established the Xiphophorus Genetic Stock Center, housed at the American Museum of Natural History and the New York Aquarium until 1993, when transfer of the stock center to Texas State University - San Marcos was completed. During its more than 70 years, the stock center has been directed by Dr. Gordon and Dr. Klaus D. Kallman in New York, and currently by Dr. Ronald Walter at Texas State University - San Marcos.

Several of the original genetic strains of platyfish and swordtails developed by Dr. Gordon in the 1930s still are available today; they are virtual genetic clones, the products in some cases of more than 80 generations of brother-to-sister matings.

From http/www.xiphophorus.txstate.edu/stockcenter/introduction.html

 

[minnnt]

So what's your take on it TTA?

 

[MBOU]

It happens, its not always bad.. like i said... used in line breeding so long as you are aware of whats going on.... and one or two generations might not necessarily cause devastatingly obvious deformities..

Seeing bags of 120 male guppies coming in and seeing at least 5 or 6 with kinked spines etc and knowing the others are likely siblings with same poor genetics.... not so fun. The things people do for the sake of new colours...

I'd not be devastated if all the big livebearer breeders started steralising the fish before exporting them... Or someone came up with the equivalent of 'the pill' for fish to be readily availeable

 

[Moby-Krib]

WOW!! I came armed with a link on depression of genes etc. in response to a certain post. The thread has grown so I'll just throw this out there. My link

In MY opinion is it can and eventually does cause malady, but this is a repeated uncontrolled inbreeding scenario and further strengthens the need for a bit of wild caught, or known genetically removed stock to be introduced on a regular basis .
confused thread but needed if any wish to breed for profit.