Crossbreeding in dairy cattle: International trends and results from crossbreeding data in Germany

Crossbreeding has been the breeding method of choice for several species in plants and livestock. In plants, the main reason for crossbreeding is to exploit heterosis effects which can be maximized via the use of highly inbred parental strains. In livestock, notably in poultry and swine, positional effects of pure-bred parents of crosses are well known and hence crossbreeding systems are set up accordingly. Compared to plant breeding, heterosis effects are not expected to be as high but are still significant and thus give an additional benefit. Breeding systems for swine and poultry thus almost exclusively use crossbreeding systems.