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The appropriate crossbreeding scheme to be applied has the structure of the introgression scheme:
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Animals from a donor breed are only used to produce the F1. In the F1 and F2 the animals are as much as possible selected for the breeding goal traits at stake in the original pure recipient breed. It might be wise that the breeding organization keeps full control over the use of the F1 and F2 animals. When If the traits of these animals appear to be far outside the breeding goal of the recipient breed, than then it should always be possible to terminate the introgression of their genes in the recipient breed.
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