Ex vivo recovery of preimplantatory embryos in bitches

The present study was conducted to investigate the timing of preimplantatory development in the dog and to evaluate the efficiency of flushing oviducts and uterine horns to collect embryos. Among the embryonic structures collected between day 8 and day 12 after ovulation, 43 % were at the 1-16 cells stage, 23% were at the morula stage and 34% at the blastocyst stage. Our collection method yielded to a recovery rate of 61.3 %, and 7.1 ± 0.7 embryos were harvested per bitch. In addition, the ovulation rate reached 11.6 ± 0.8 per bitch. The first morulae were observed from day 9 post-ovulation, while the first blastocyst appeared from day 10. Two-thirds of the collected morulae-blastocysts were obtained between the 11th and the 12th day after ovulation. To the moment, we suggest this is the best period to harvest canine embryo for cryopreservation.