I was visiting someone recently on a separate matter but he happened to have a litter of eight-week-old black labs. I asked if I could see them and they are eight big, beautiful, healthy pups, strong boned, lovely heads, dark eyes. A very even, nice litter, half boys and half girls. Then he told me that the parents were litter brother and sister and the mating was an accident (this was true). What does this mean for the pups? Are they as you see them (good-looking, strong pups) or does a close family mating like this bode trouble for the future? I am not after a pup (I have three dogs already so I am full up) but I am curious to know what this means. He has not advertised the pups. He has both parents, good gundog stock, so maybe he will find homes amongst his shooting friends. Thanks for any comments.

If both sire and dam are healthy (physically, mentally and genetically) then the pups should be the same. Basically, all the genes are being 'strengthened', the good ones as well as the bad - good points as well as faults will be more 'fixed'. If there are no serious faults in either parent, then there shouldn't be a problem. It's not something to be undertaken lightly, though - let's hope he's got away with it!
:)

Thank you everyone for your replies. I don't know much about the intricacies of breeding. As the pups look so good I was just wondering whether something could pop up unexpectedly in the future as a result of the close genes. I had expected the pups would have obvious problems (like five legs!) and I was surprised they look so good, and all so even. Both parents are lovely looking dogs with great temperament, but just young (two years - must have been the bitch's second season), and the man kept them out of a previous litter, for working. He has three generations of that line, well, the grand dam and the two parents. He shoots and all his dogs are working dogs. He is a close neighbour of mine so I will keep an eye on developments. As he works all his dogs regularly, I guess he will place the pups in working homes. Thanks for all the info - it's a great site for information, you lot are highly knowledgeable and it's great to be able to tap into it! :)

The important thing to remember about very close matings like this, is that it can't introduce genes that aren't already there. What it will do is make them more evident.
:)

I once saw a GSD from a litter brother/sister mating.The dog had looked normal as a pup and both parents were okay but the pup ended up with a normal body and little stumpy legs!!Did look strange poor thing.
Archer

No ..... ! Isn't that illeagal? I've got a very randy 9 month old lab who's gagging for it - my mate's got his sister - do you think we could chance it and let them get rid of their frustration???

It's not illegal but it is as Jeangenie said, not something to be undertaken lightly. I would want to know the sire and dam very well before I would even bother to think about having one of the puppies. One thing is certain, It would be extreamly unlikely that any recessive fault would NOT come out in the puppies. Just because the sire and dam appear ok does not mean that they are not carriers of something nasty and because of the relationship both are likely to be carriers of the same problem!

Regards, John

As you say, John, you'll certainly find out what recessives/mutations the individuals are carrying, because it's almost guaranteed to be carried by both, so will 'come out' in the pups.

Surely any recessive trait needs both parents to have that trait AND that trait to be inherited from both parents.
So a brother sister mating does increase the probability that this will occur but it is not certain.
Simple genetics is that you inherit one of each pair of genes from each parent. SO any gene must be passed on to 50% of offspring (on average). Where both parents have a recessive gene you have a 1 in 4 chance that this will be 'doubled up' in the offspring. So 1 in 4 will inherit a double dose, 2 in 4 (50%) will become carriers ie one normal and one recessive gene and 1 in 4 will NOT inherit.

It is NOT a mating I would do but I can see no major problem with a one off brother - sister IF both parents are sound.

A 1 in 4 chance that my puppy would not inherit anything nasty or be a carrier for it means that there is a 3 in 4 chance that it will and that does not sound like a reasonable risk to me! Sorry LD, but I disagree on that one.

Regards, John

No Anna, don't do it!!!
It won't get rid of his frustration - it'll only make him worse.

Hi Anna,

I agree with Jeangenie, it will make him impossible to live you, if you are not intending to show him or use him at stud regularly, your best bet would be to neuter him at about a year old, especially if he is being a pain!!

Brother and Sister matings, as others have said can throw up bad faults, as the genes are being doubled up more than other close matings, such as grandfather to granddaughter.

If you were going to breed a bitch who was from an accidental B/S mating, it would be a good idea, to outcross some degree to try and introduce new genes to strengthan the line again. Line breeding is all very well, but does have it's risks if you are not careful (and even if you are sometimes!!)

manda
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