Breeding half siblings

[Shylah]

Hi everyone,
I'm new to the forum and would like some advice. My friend has 2 sphynx that have different mothers but the same father and they ended up mating. She is now thinking about continuing to mate them. I was wondering what the risks are with this coupling? I don't know much about cat breeding but do know that there are top breeders in the dog world that will breed a father and daughter without it being frowned upon.
I was hoping that breeders who have experience would be able to give me some advice to pass on to her. I would also like to hear what people think about this as I was thinking about getting one of the kittens.

Thank you in advance for the helpful and polite advice.
Shylah

 

[ElvirasMum]

U
If, they have the same father then half of their dna is identical and that would be in breeding. The entire point of responsible breeding is for genetic soundness not further instability by using inbred cats. Your friends decision is immoral and irresponsible and selfish. Your friend may not suffer but the kittens certainly will.

 

[susi794]

It's called line breeding....and there is nothing that wrong with it.....except if there are any bad genes, they are multiplied by this pairing. The kits should be fine. It's not usually done unless you are trying to amplify a certain trait that is highly sought after. Totally unrelated breeding is much better.

 

[susi794]

This comes from the GCCF (Governing Council Cat Fancy)



Inbreeding
Inbreeding is an inclusive term covering many different breeding combinations and degrees of
relationship – including the more distant, less intense; the latter is sometimes referred to as “linebreedingâ€.
In-breeding is consistently more efficient in eliminating heterozygous (varying and diverse)
genotypes and increasing homozygous (same) genotype, thereby ensuring a greater likelihood that
kittens will closely resemble their parents, which is the essence of any breed of pedigree cat. Used
here, the term does not mean close, purposeful, inbreeding of closely related cats (brother/sister,
father daughter), but rather the moderate form that results from the mating of not too distantly related
(but not directly related) cats (first cousins, half brother/half sister, second cousins, etc). Some inbreeding
is essential to stabilise conformation around a definite type and to maintain the integrity and
distinct physical and genetic characteristics of any breed of pedigree cat. In-breeding is the act of
mating individuals of various degrees of kinship, if continued it produces ever increasing homogeneity
in the offspring.
It is recognised that breeders may want to test for any genetic anomalies in their own lines and that
the mating of very closely related cats is the simplest way to do this, unless a DNA test is available
(which they increasingly are – see list at link). However, the GCCF requires any kittens bred from
the following matings of closely-related cats to be placed on the non-active register in order to
prevent the inheritance of any detrimental genetic traits by subsequent generations, unless
there is a specific purpose which has been advised by veterinary or genetic counselling and is
supported by the relevant BAC and/or approved by Executive Committee:
i) Mother to son ii) Father to daughter iii) Full siblings
In essence the overall approach should be one of balance and moderation in the degree of inbreeding
coupled with consistent selective breeding with a clear objective in mind – ie the
improvement of a key aspect and/or the elimination of weak traits or defective genes.


So line breeding needs to be done by responsible, knowledgeable breeders. These kits are not going to be deformed or anything, but their chances of ill health could be intensified if one of the parents have a genetic defect already.....line breeding intensifies good qualities but it also intensifies bad ones.

 

[Caloci]

As Susi said line breeding is common. I think it is risky unless you know a lot about the line you are dealing with. I feel that it is better left to the experts who do the DNA testing and what not. I also feel that it is not the best practice in a breed that has a small gene pool. Also, it is best if the parents and offspring have a pedigree so that the offspring do not inadvertently continue the line breeding and create more health problems.

 

[Shylah]

Thank you very much Susi! That information helped tremendously, I will definitely pass it on. Her cats are from champion lines and are show quality. I know she has the pedigree for both so she is informed when it comes to that. From what it says I think it would be best for her to have the kittens spayed/neutered before selling them to avoid any possibility of them mating with another relative.
Im sure she will appreciate all the info...any other helpful information is appreciated as well.

Thank you,
Shylah

 

[susi794]

You're quite welcome.

 

[Crinkuls]

In breeding was done in UK years ago when the first sphynx came here, my first sphynx Crinkuls who I had for 12 years was the result of having her dad bred with its own mother. This was now many generations ago and as far as I know doesn't happen any more as there are plenty of sphynx here. That was the time that Devon Rex were also used. Her pedigree papers are very interesting if a little incestuous and show her coming from the very first Sphynx cat ever to come to UK( Hather de Calicat aka Tulip)

These are the 2 rat bags I have now. They are cousins but very different. One a bit fuzzy round the tail and slight fuzz on body but Princess is as bald as a coot.

 

[susi794]

I will have to remember "bald as a coot"--what a wonderful phrase that is!

 

[Shylah]

These are the 2 rat bags I have now. They are cousins but very different. One a bit fuzzy round the tail and slight fuzz on body but Princess is as bald as a coot

Your babies are gorgeous!
@ bald as a coot

 

[Crinkuls]

Another Brit expression is "bald as a badger" but the badgers I've seen have never been bald.......unfortunately just squished on the road side

 

[Karey Kelly]

Inbreedi

It's called line breeding....and there is nothing that wrong with it.....except if there are any bad genes, they are multiplied by this pairing. The kits should be fine. It's not usually done unless you are trying to amplify a certain trait that is highly sought after. Totally unrelated breeding is much better.

This in information was super helpful and assisted me further in my web searches! Thank you

 

[Karey Kelly]

This in information was super helpful and assisted me further in my web searches! Thank you