The Zim Family Cocker Spaniel Forum

Hi All,
I have a question about the current definition of inbreeding versus line breeding.

Personally, I will never breed. But there are recent talks by people about breeding a bitch to a grandfather, breeding two cousins where the sire of the bitch and the dam of the dog are littermates, breeding a bitch to the littermate of her dam. While I understand dogs are not humans, some of these breeding proposal makes me wonder. Experienced breeder, where do you draw the line?

BTW, some of these proposed breedings are discussed on a foreign cocker forum where I am part of.

Thanks.

I'm not an experienced breeder, or rather a breeder at all.. But I know what you're saying.
I'm also curious. Please someone enlighten me!

The perfect breeding is when the kids are in a loving home...

Robbie and I have talked about breeding as well, just not ready to raise the whole litter our self's just yet...

I'm probably not the best person to respond to this, but out of the short amount of time I've been in the show world, I've learned the difference.

Breeders line-breed to get a consistent type in their line. For example, if you bred a bitch to her grandfather, then chances are the kids will be more consistent in type. I've seen this done multiple times when breeders are trying to incorporate a certain style. Rexpointe Cockers did this, I think, which is why people were able to distinguish which dogs she bred just by their appearance. I use Rexpointe because everytime I look in an old leader now, I can point out a Rexpointe dog from a mile away. That's one purpose of line-breeding.

Breeders, you can correct me if I am wrong.

The breeder I got Abby and Ava from does line breeding...for a matter of a fact my girls are a result of line breeding. My girls have the best temperament you could ask for! They reallly are jewels in every way. The breeder knew what would be produced.

I understand the point of line breeding. Although my Heidi is a rescue, she is a line bred dog with a very respectable pedigree. Everybody can tell that Heidi is a line bred dog of Palm Hill's Krugerand "Randy" way before we found out about her pedigree. And Heidi agrees with the description of "Randy" very much.

My question is where is the line between inbreeding and line-breeding? How far is too far? As everybody knows, breeding close relatives can amplify recessive genetic traits, including undesirable traits.

Debbie, I disagree with you that the breeder always know what they are going to produce. After all, I am not saying that there is right or wrong. They do make mistakes. Some are very honorable and learn from it.

I assume that most people would call breeding a sire to a daughter will be inbreeding. But why is breeding a grand sire not inbreeding?

There has to be a certain COI before it's considered inbreeding. If you breed a bitch to her grandfather (which I am considering for Toph BTW) there is not a high enough COI to be considered inbreeding. This should help answer your question http://www.showdog.com/help/topic.aspx?id=74

Thanks Julie for the definition using COI. And I am sure you have done your research regarding Toph. We know that you love her very much and would only do what is responsible.

That said, why is 12.5% ok and 15% is not? Are there research to back those numbers up?

Also, often times, breeding a grandparent to a grandpup can result in more than 12.5% COI because the grandparent often shares some ancestry with the pup's other parent. So the effective COI could be higher than 12.5%. Is there a COI/Pedigree calculator/estimator out there?

Yes exactly Stella, if there is more than one common ancestor then the COI would be higher.

Why 15%? I'm guessing some geneticist at some point did a study. Maybe it was this guy Wright who developed the COI Can I point you to that study? No. It's pretty commonly accepted though.

http://www.canine-genetics.com/relation.htm Maybe this will help more? I'm sure I've read of a COI calculator somewhere. Perhaps a google search would turn one up?

Here is one. http://www.czerwonytrop.com/inb/index.p ... =ok&lng=en It says ideally the COI should be under 3%? That is virtually a total out cross with no ancestors in common.

Stella, my answer was somewhat hypothetical..not carved in stone of each quality, just like you have a good idea of colors but not that you will definitely get each of the possibilities. I do know my breeder matches them up for certain qualities (beauty and temperament), and if she has a dog with undesirable qualities, she will not breed them. One example is my Ava's underbite...she was originally kept for show and breeding, but when she developed the underbite she did not want to pass it on and sold her as a pet (so happy she developed that bite ). A good breeder knows what they WANT to produce and work toward that. Often times line-breeding produces these qualities or that is how I understood it when she explained it to me.

When I first saw their pedigree I thought inbreeding ....but it has been confirmed it is only line-breeding and fine.

Thank you Julie and Debbie.

Here is my personal take on the definition. I think the 15% COI is just a general guideline to guard against massive disasters. For the breeding of close relatives (the ones lower than 15%) to be called line breeding, the breeder MUST know what are the desirable traits that they want to preserve and are willing to eliminate puppies with undesirable traits from their breeding program and place them in loving homes.

And Debbie, I have heard good things about your puppers' breeder. While she does not have control over how each individual pup will end up, she knows how to control her breeding program to produce healthy, beautiful pups with good temperament on average. And yes, I agree that is line breeding.

And people should be alarmed when they see pedigrees with lots of common ancestry. Hey, we have to be able to tell the breeders who know about line breeding versus those who are breeding two close relatives out of convenience. As Debbie has pointed out, the ones who know what they are doing can explain the things clearly.

Debbie, I know that you have talked about it is the greatest blessing that Ava got the under bite. I think the best gift that my Heidi's breeder has given her was that she sold Heidi to her first mom as a pet with a limited registration and spay contract.

Stella, I agree all around with the above post.

Trust me, I don't line breed for beauty. If I bred anything for beauty I've got scores of choices of some of the best physical examples of our breed within minutes of me. I love seeing a breeder with generations of healthy, long lived dogs in their 'kennels'. Dogs whose sons, granddaughters, great nephews are 6,7,8 years of age and still eye clear. Dogs who I can look up on offa.org and find three or four generations of almost every dog hip certified, plus a list of half brother and sisters, and offspring (love those older dogs). At this point in my breeding with many of my dogs DNA tested for Prcd/PRA and clear for affected and carrier, no incidence of cataracts besides Pirate's nutritional ones, no luxating patella's, and very few incidents of hip dysplasia,and obviously I'm not going to double up on the dogs I suspect were the carriers (which were outcrosses to my stuff BTW), I feel confident line breeding on this line. It's more scary for me to outcross. I've done half brother to half sister breedings on my old dog Marshall Dillon, and grandfather to granddaughter with him as well. Some of my healthiest long lived dogs came from those breedings. It didn't hurt that they were beautiful too!

Just like in any breeding, people can linebreed for the wrong reasons, like JUST setting type, without any regard to the health. That happens every day anyway.

words from a good breeder IMO

I wish Julie bred Cavaliers, I would import one in a heartbeat!

That is really nice of you guys to say. Thanks. I have selfish motive too. I personally want my dogs to be with me as long as possible. While I obviously can't control every last thing, I want my dogs to be as healthy as they can be during that time.

And in about 3 years, I would appreciate if you can direct me to a r/w that can finish in breed and have the structure to do agility, tracking and obedience/rally.

Thanks,

Colleen

Well Colleen, don't count on me. I've been looking for a R/W for about 15 years and still haven't found a quality dog or bitch that IMO was worthy. If you find one, let me know and I'll buy the littermate lol!