14.7 Prevention of inbreeding

In the long term the average additive relationship in the population determines the constrained inbreeding. Therefore prevention of (forced) inbreeding highly depends of the methods to manage relationships among animals in the population. In commercial breeding populations a lot of effort is applied to manage this, although random effects (e.g. a selected animal produces no offspring) might disturb the intentions of the mating program. In less controlled breeding programs it is very difficult to realize management programs to control relatedness. Then it is wise to give breeders inside in the implications of mating relatives and to stimulate individual breeders to apply matings that all together have a favourable effect on the average additive relationship. A mating advice (which sires can be mated to this individual dam to minimise the increase in relationship in the population) might be of great help.  

What measures will help to cease down in a population the increase of the average additive relationship and have therefore a favourable effect on the rate of inbreeding? Three measures might be effective:

1. Expansion of the size of the effective population

2. Restrictions in the number of offspring per parent

3. Mating schemes to control and manage relationships