This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by ROWSON, L. E. A. Articles by MOOR, R. M. Search for Related Content PubMed Articles by ROWSON, L. E. A. Articles by MOOR, R. M.

EMBRYO TRANSFER IN THE SHEEP: THE SIGNIFICANCE OF SYNCHRONIZING OESTRUS IN THE DONOR AND RECIPIENT ANIMAL

Summary.: Morulae and blastocysts obtained from ewes 5, 7 and 9 days after oestrus were transferred to 120 recipients whose oestrous cycles were either synchronized or ± 2 or 3 days out of phase relative to the onset of oestrus in the donors.

When synchronization was exact 75% of all recipients became pregnant. A high proportion of pregnancies were, in general, also obtained where the onset of oestrus in the recipient differed from that of the donor by ±2 days. With a difference of ±3 days, however, only 8 % of ewes became pregnant. The survival of 5-day morulae transferred to 7-day recipients was lower than when 9-day blastocysts were transferred to 11-day recipients.

The results are discussed with reference to possible factors associated with early embryonic mortality.