ancestral loss coefficient [AVK]
What is the AVH?
This I would like to explain with an example:
The mating of two siblings shows that you have been to the 2-generation ancestor loss. "Sarah" from the blue road "has thus no more 4 grandparents, but only second
In humans, such a mating would be to today's Time to think hard. In dogs can be so, or in later generations often. An ancestral loss is therefore, if an ancestor more than once in a pedigree.
But what's so wrong with that?
The ancestral loss can lead to the accumulation of harmful recessive genes for traits that influence and reinforce each other and thus reduce the vitality and cause only work together as the most genetic diseases (eg HD = hip dysplasia). The aim should be to heterozygosity, as far as possible reached to breeding within breeds! Say, the greatest possible genetic diversity. Of the about thirty thousand Genes of the domestic dog, we affect the breeding for conformation perhaps thirty.
When you select this line and intensive farming runs, then the offspring look uniform "breed type" from. It was then inevitably other genes located in a homozygous form. These may then also be harmful alleles are either recessive genetic diseases in a simple form or even genetic diseases with a polygenic process (such as HD etc.). It can also be forms of the process of influencing the growth, the nature, strength or fertility (etc.).
But what's so wrong with that?
The ancestral loss can lead to the accumulation of harmful recessive genes for traits that influence and reinforce each other and thus reduce the vitality and cause only work together as the most genetic diseases (eg HD = hip dysplasia). The aim should be to heterozygosity, as far as possible reached to breeding within breeds! Say, the greatest possible genetic diversity. Of the about thirty thousand Genes of the domestic dog, we affect the breeding for conformation perhaps thirty.
When you select this line and intensive farming runs, then the offspring look uniform "breed type" from. It was then inevitably other genes located in a homozygous form. These may then also be harmful alleles are either recessive genetic diseases in a simple form or even genetic diseases with a polygenic process (such as HD etc.). It can also be forms of the process of influencing the growth, the nature, strength or fertility (etc.).
calculation of the AVK The AVK
calculated from the ancestors really exist [Av] and the theoretically possible number [Am] of ancestors.
AVK = Av / Am
For two generations, Am = 6;
for 3 generations, Am = 14; is
at 4 generations Am = 30;
at 5 generations on = 62
example
Bluna of Pinn's Hof over 4 generations. On = 30
Pieter is 2 times before, will trigger a
Kimberly 2 times before, will trigger a
Ignatia 2 times before, trigger a total withdrawal
3, ie Av = 30-3 = 27
AVK (4) = 27 / 30 = 0.90
The loss of ancestral Bluna is over 4 generations, ie 90%.
Note: The PAD should normally calculate more than 5 generations. For Bluna then the AVK 85.48%
A rule of thumb would say, not the AOD should fall below 85%. The AVK is always considered along with the inbreeding coefficient [IK].
The IK is explained in the next blog!
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