Ancestor-Loss coefficient (AVK)

Since the inbreeding-coefficient (IK) shows only the relation between 2 partner-dogs, out of a match of 2 highly inbred dogs (e.g. a match of 2 littermates) which themselves come out of 2 non-related parent-dog-bloodlines, we can get an IK nearly 0% (because there are no common ancestors in the sire's/dam's bloodline). This simply means that for breeding-purposes very important information isn't shown at all. A very simple method to overcome this problem is the calculation of the AVK. This method doesn't replace the calculation of the IK but gives for the enough information for the average breeder.

Ancestor-Loss is given when the same ancestor appear more than once in the pedigree of the dog. A 5-generations-pedigree shows 62 possible ancestors. If one of this 62 possible ancestors appears twice, the dog in question has indeed only 61 different ancestors. If 3 ancestors appear twice, this dog has indeed only 59 different ancestors. The AVK is calculated out of the no. of the ancestors and the total no. of possible ancestors.

Pedigree of Bessi

Example: Pedigree of Bessi
The ancestor Horrido appears twice, so from 30 possible ancestors you subtract 1. The AVK can now be calculated like this:

AVK = 29 / 30 = 0,966

The AVK of this dog is 96,6%.

Pedigree of Japsi

Example: Pedigree of Japsi
Here you get the following calculation:

From 30 possible ancestors you have to subtract 9. The AVK for Japsi can be calculated as quotient;
AVK = 21/30 = 0.7

So, Japsi has only 70% of the possible ancestors left.

The AVK depends on the number. of generations it is calculated over. There is normally a loss from generation to generation as most dogs go back to the same roots/ancestors. The example of Japsi shows over 3 generations the AVK of 85.71%. From the 14 possible ancestors, 2 appear twice. Therefore the calculation is 12 : 14 = 0.8571. Make sure that if you compare the AVK with examples from other sources, to look at the number of generations.

Source:  Hundezüchtung in Theorie und Praxis von Walter Schleger und Irene Stur; ISBN 3-224-1 7000-8 Jugend und Volk Wien