The use of embryo transfer (ET) in cattle breeding offers a possibilit
y to increase the progeny of genetically valuable high-performance cow
s. The present study aimed to find out in how far this goal could be a
chieved under the conditions of practical cattle breeding. 3249 cows o
f the black and white dairy cattle of the former G.D.R. were analysed.
The superovulation rate decreased from 90.1 % to 80.8 % from 1987 to
1989. Furthermore, it was influenced by the breeding plant and the ind
ividual donors. The number of intact embryos obtained per donor flushe
d is strongly dependent on the given breeding plant, SO-regime (PMSG;
FSH) and the mating bull. The pregnancy rate following fresh transfer
was most strongly influenced by the breeding plant and the donor withi
n the plant. Furthermore, the PMSG procedure was demonstrated to the s
lightly superior. The number of calves born from ET per donor cruciall
y depended on the number of intact embryos obtained, and on the pregna
ncy rate and is most strongly influenced by the level of given breedin
g plant. 2.0 calves per donor were born, 1.9 from these were intact an
d 0.39 male calves per donor were used for breeding only.