Everything we see or measure from an animal (a dog) is the sum of the genetic predisposition of an animal as well as numerous environmental influences. For breeding, only the genetic predisposition is important. Our own measurements and the performance of an animal are not enough to accurately predict the genetic predisposition of an animal.
What are breeding values?
A breeding value is a mathematical method in which the genetic predisposition of an animal for a particular trait can be estimated. It estimates how good the animal as a parent for the next generation will be. In other words: it estimates the value of the animal for breeding: this is called the ESTIMATING BREEDING VALUE.
First of all, we gather as much information as possible about the dogs (pedigrees, health screenings, assessments, etc.). This information is entered into a specially designed computer program in a standardized manner.
The data is processed into breeding values based on the animal model. The calculations are done by the BLUP system (BLUP = Best Linear Unbiased Prediction).
The animal model requires 3 sources of information to be utilized, namely the characteristics of the animal itself, the characteristics of its parents and other relatives as well as the characteristics of all its offspring.
With each breeding value the computer calculates the reliability. This is a number between 0 and 99%. This depends on the amount of information processed and the heritability of the characteristic for which the breeding value is calculated. The more information from parents, relatives and descendants is known; the higher the reliability will be.
How does it work in practice?
EBV’s can be calculated for each inherited defect or characteristic. These are then converted to a figure for each characteristic with an average of 100.
A dog which has an EBV of 100 means that he will inherit the characteristic, according to the average of the breed. However, if he has an EBV below 100, then we assume that he will have a negative impact for this characteristic on his descendants. When puppies are born, they get an EBV which is the average of the EBV’s of both parents (EBV father + EBV mother/ 2). Generally, it is recommended to achieve better than the breed average. In other words, one must ensure that the average of a combination (male + female) is higher than 100.
Therefore, it is recommended in the beginning not to publish the individual EBV’s of each dog. Instead the computer will calculate for each bitch an individual list with all the appropriate males (based on the EBV’s of the combinations).
The breeder will receive this list with all the appropriate males (based on EBV’s) in alphabetic order. By choosing either of these dogs, the breeder will produce a litter with EBV’s better than the average of the breed. In this way, the population will improve by each generation.
In the future, when a breeder chooses a combination according to the breeding advice, a note should be printed on the pedigree of the puppies, certifying that this puppy is originated from a scientific responsible combination.