Determining the sex of bovine embryos using polymerase chain reaction results: a six-year retrospective study.

摘要

Data on 4183 embryos biopsied and diagnosed for sex over a 6-year period were analysed. Sex diagnosis was made using a 165 bp Y-chromosome-specific sequence or a 210 bp autosomal sequence. The embryos were biopsied by 3 methods: blade (230 embryos);aspiration (1148); needle (2905). Fresh or frozen embryos were transferred non-surgically to synchronous recipients. For the 3 methods, the percentage of embryos in which the sex could not be determined was 14, 14 and 8 respectively. Pregnancy rate washigher for fresh than for frozen embryos (58 vs. 37%; P<0.05). Sex diagnosis using the PCR showed 93% agreement with results from ultrasound testing after day 60 of pregnancy. More embryos biopsied during October-March (least daylight) were diagnosed asfemale than during April-September (48 vs. 44%; P<0.05).