Review on international trade with boar semen.

For more than 40 years, AI (artificial insemination) has been carried out with pigs. In some countries, it constitutes since the 1990 s the dominant procedure with piglet production to fertilize the sow. This procedure of insemination with fresh semen has become prevalent in all countries on a worldwide basis with an important pig meat production, with the exception of China. Meanwhile, up to 90% of the sows have been artificially inseminated. The trend is still upwards. As the need of pig meat and thus the production continues to increase, one can proceed on the assumption that the number of semen doses, which is necessary for this procedure, will likewise increase correspondingly. Until now, the trade beyond borders has only been marginal. An improvement in the sense of a longer shelf life for semen doses is indispensable for the trade over longer distances.