Title of the paper: Embryotransfer with recurrent donors. The repeated
ly stimulation of ovaries of cows by hormones is possible during both
one and more than one lactations. The reactions of ovaries indicate a
large variability. Therefore this procedure depends on optimal herd- a
nd farmmanagement. It is necessary to examine the sperm quality of bul
ls with respect to their use in ET-programms. A necessary condition fo
r further superovulations is the yield of 6 transferable embryos after
the first superovulation. The total number of superovulations is not
projectable. When the yield of embryos decreases from one superovulati
on to the next, it is advisable to change the treatment management.