Laparoscopical intrauterine insemination with different doses of fresh, conserved, and frozen semen for the production of ovine zygotes.

The objective of the present study was to increase the efficiency in the production of ovine zygotes suitable for microinjection via laparoscopical intrauterine insemination. In the first part of the study, 71 ewes of three different breeds were inseminated with one of two different insemination doses (50 x 10(6) or 300 x 10(6) sperm per inseminate) and semen was either freshly diluted, liquid conserved, or frozen/thawed, or females were mated by a fertile ram (controls). In the second part, a total of 46 ewes was inseminated with 300 x 10(6) freshly diluted sperm to verify the findings from part 1 and to unravel effects of breed and age of donor ewe.