The reproductive success in domestic animals is an important factor to
wards the ecomical production of livestock. Thus, a lot of energy has
been spent on the amelioration of the reproduction by means of genetic
s but no considerable success was achieved since the additive genetic
variance is low, This communication is supposed to elucidate its molec
ular biological basis in reproduction and furthermore, the article sho
uld point out the way in reseach how to improve reproductive parameter
s. We propose to characterize all sorts of genes and their gene produc
ts that are involved in reproduction. This is to realize a full unders
tanding of the sperm egg interaction and to derive benefit from effect
s like heterosis.