Inbreeding/Line Breeding - Page 1

Can you/should you take a Father to a Daughter when inbreeding? Has anyone ever gone through this & seen the pros/cons of the offspring? Health problems?

What’s the best combination/quickest way of line breeding when trying to achieve the father’s traits?

Hello Friend,

This inbreeding would produce an outcome that is 75% the sire (because he is 50% the father of the litter and 25% as the grandfather of the litter). The Coefficient of inbreeding will be 25%. Super, super high and risky! If you want to preserve this dog's genetics and pass on his traits, there are two possible approaches that will involve less risk. The first approach is the half sibling approach. Mate him to two completely un-related females, but whose temperament and structure compliments him. Take a male puppy from Female-A and breed him to his half sister, from Female-B. This will produce a puppy that is 50% the sire, as opposed to 75%. But the COI drops from 25% to 12.5% and you risk is reduced. You need to go to embarkvet.com and order a test kit and test for genetic diseases first and foremost prior to doing any of this. You don't want to double up on any genetic diseases, so be sure none of the pups are carriers for Degenerative Myelopathy or epilepsy or any other disease, PRIOR to breeding.

 

The second approach is what is called a 2-3 line breeding. Take an adult daughter of this male, and breed her to a completely unrelated dog, of good character and likewise, genetically tested for no diseases. The pups that come out are therefore grand-kids of your dog, the original sire. Take the original sire, and breed him to a different mother dog, and keep a son from this breeding: the very best son, not just any son. Then, take the son of this stud dog and mate him to a grand-daughter of this stud dog, from the other daughter he has from the other female. In other words, via Female-A, you produced a son. Via Female-B you produced another son or daugther. Via the son or daugther, get a grandkid of the original dog out of them. So from female-B, your goal was to get a grandkid of the original dog, not a kid of the original dog.  From this son, or daugther get a grandkid out of him, of the original sire. Then take the grandchild on one side, to a child on the other side. To be clear: From Female-A, you produced a child of your male.  From Female-B, you produced a grandchild.  So it's a two step process, a child, followed by a grandchild, from Female-B.

This will produce a dog that is 37.5% the original sire and the coefficient of inbreeding drops to 9.63% from 12.5%. This is known as Bracket's formula: "Let the sire, of the sire, be the grandsire of the dam". If you couldn't follow this, the video and the URL explains it.

The quickest is not the safest. That's why I recommend an approach that will preserve most of the traits of the original dog, but reduce the odds for disease.

https://breedingbetterdogs.com/article/brackets-formula

there is NO secret formula, you allways would have to look at the individual dogs you use, the percentages mentioned by previous poster are theoretical, so I generally agree with the post,but must say its not functional, as every dog from every combination is different geneticly, some dogs tightly linebred can have less actual genes from desired ancester than others less closely linebred on said dog.

I did strong linebreeding and would say best oucome for me was half brother halfsister , and got good results on pairing ofspring of full littermates, so breed a daughter of the desired male, to a son of his sister or brother, again, the dogs should be selected for this, line and inbreeding based on names on paper only is worthless

@alexnds05 & @duke1965 thank you!

@alexnds05
Now if I do the half brother, half sister pairing & take the very best female from that offspring. Can I breed the female BACK to the original Sire? If I did so what would my percentages/risks look like?

Based off the video link, he said doing the half brother / half sister didn’t produce the best offspring… thoughts?

Now using the Brackets formula, if I were to take the granddaughter to the son of the original sire. They produced offspring. I kept the very best FEMALE from this breeding. Then could I take her back to the original Sire? Once again what do the percentages look like/risks?

GSDvonJägersHouse

There is a difference between these 3 strategies:
a) Line Breeding
b) Back Breeding
c) Inbreeding.

b) and c) are the same , in that they are both inbreeding. So what is the difference?
Inbreeding involves close relatives in the same generation , such as full brother and full sister, or half siblings. It also involves parent to child, and grandparent to grand-child.
a) Line Breeding involves breeding animals "in line" to the common ancestor. That means the common ancestor appears on the top and bottom of the pedigree, but in different positions in the pedigree. For example, he (or she) might appear 3 generations ago on one side, and 4 generations on the other side. Or for example, the common ancestor might appear in the 4th generation on both sides. This is a 4-4 line breeding. Or it might involve the same ancestor appearing several times in the pedigree, for example:
5,4,4-4,4,4 . The effects are cumulative. The genetic influence is cumulative. So if the ancestor is "up close" in the pedigree, his influence is greater. If he is further back in time, his influence is smaller. But if you repeat this ancestor, you are increasing his genetic influence, but still preserve hybrid vigor because a lot of other animals are involved.

Bracket's formula, if you understood the article is called a 2-3 breeding or a 3-2 breeding. In first case, the male dog's father is the female dog's grandfather. In the second case, the male dog's grand-father is the female dog's father. The first case represents an half-uncle to niece mating. (not a full uncle, but a half uncle). In the second case, it represents a half-aunt to nephew mating. (not a full aunt, but a half-aunt).  If you understood his method, you are trying to accomplish more pre-potency than a first cousin mating (which is 3-3) or a second cousin mating, which is 4-4.  But you are reducing risk by being below the level of half sibling mating, which is 2-2.  So why breed back yet again? You are defeating the purpose of this kind of mating in the first place which is to create pre-potency but reduce risk.  Your question means you didn't fully understand the Bracket method. The Coefficient of Relationship for half siblings is 50-50 and the COI is 12.5%  The Bracket Method accomplishment is a 37.5% Coefficient of relationship and a 9.63% COI. Notice how 37.5% is 12.5% below 50% of half siblings. Notice how the COI is 9.63% which is below 12.5% of half siblings. See how that works? So if you understood his idea, it was to accomplish pre-potency but reduce risk.

I have absolutely no clue why you insist on breeding half siblings of a common male, which is a 2-2 breeding and will create offspring that are pre-potent and homogenous for a lot his genes and then want to breed back to him YET AGAIN! Why? You have already created "pre-potency" in the first situation. There is no reason to breed back to him yet again. What exactly are you trying to accomplish here? Do you have a clear goal in mind? Remember, for every 10% increase in inbreeding there is a 10% decrease in litter size. There is far greater risk for disease as you inbreed further and further. You are trying to strike a balance between creating pre-potency and consistency in the litter, versus complete risk and genetic defects and birth defects. That's why COI understanding is so important.

Are you creating a new breed based on this dog or are you trying to create a line of dogs in an existing breed? In other words, let's say you are trying to create a new breed. You have "colony-A". Your male was a Cane Corso and the two females are American Bulldog females. The offspring are a mix of both breeds, but the Cane Corso dog would be pre-dominant. If you then bred these half siblings together. Separately you would do a separate "colony-B" of dogs where the father was an American Bulldog and the two mothers were un-related Cane Corso females. You would then breed these siblings to each other. You would then take puppies from "colony-a", where the Cane Corso male was the common father, and "colony-b" where the American Bull dog was the common father. So in this way, half siblings of Colony-A are bred to each other and half siblings of "colony-b" are bred to each other. After 20 years of work, you would create a new breed that "breeds true". That is how a new breed is started.

In your case, you are NOT starting a new breed. You have a German Shepherd and you want to breed father to daugther or grandkids, that are already 50% their father back to their grandfather. You are simply going to create a bunch of very diseased, mentally ill dogs. Don't do this. My explanation above is a safer approach, A 3-3 or a 3-4 breeding is much safer. Half sibling approach is going to work to accomplish pre-potency but I wouldn't go further. If you insist on breeding back to your dog and you ignore everything I wrote then perhaps you shouldn't inbreed at all. The video below will help you if you will listen to it in full.

No, you absolutely should not.