| The embryo transfer of ewe is an advanced technique. It is a complex process, including many segments, such as estrus synchronization, superovulation, egg collection, embryo investigation and implantation, etc. Each segment of the process is very important. If one segment fails, the embryo transfer will not be successful. The successful rate of the embryo transfer is low due to the complex process and many unfavorable factors in each segment.B-mold ultrasound scanner is able to scan the ultrasonogram of tissues and organs without pain and damage. It was used in this study for monitoring dynamically each segment in the process of embryo transfer, in order to reduce the rate of problems in each segment and increase the successful rate of embryo transfer in ewes.1. Sonographical anatomy of the reproductive organs of eweIn order to confirm the positions of several reproductive organs in living body such as vagina, uterine, ovary and the nearby organs from the ultrasonogram taken with B-mold ultrasound scanner, slaughter of ewes was used as the control. The results indicated that the optimum position for the transcutaneous scan with 3.5 MHz sector probe was in the less hair area between thigh inner and breast upper. The 5.0 MHz linear probe was used for transrectal scan. The ewe was restrainted standly, and the faeces in rectum was removed. The long-handle probe was inserted into the anus slowly with the scanning side facing below. The ultrasonogram of vagina, cervix, urinary bladder were present.Then it will present uterus and ovary when the probe scanned frontly and within 45 angles. The medium-intensity echo structure of the uterus and ovary were seen cleanly in front of the anichoic area of urinary bladder. The hyperechoic surround membrane was distinct. The hyperechoic pubis with acoustic shadow was found in the borders between belly and pelvic cavity. The ultrasonograms were confirmed by immersion scan and intraoperative ultrasonography.2. The simulated experiment and appiicational experiment of embryo transfer in ewe and the monitoring technique by B-mold ultrasound scannerFirstly, a simulated experiment of embryo transfer in ewe has been carried out on dairy goats and sheep, and then an appiicational experiment has been filished in a Boer gaot farm and a Poll doset sheep farm. It was successful. The donors were treated with FSH for superovulation decrease by decrease. The recipiends were treated with CIDR and PMSG for estrus synchronization. Six days later, embryo collection and implantation operation was taken at uterine horn. All of the processes were monited by transrectal scan with 5.0 MHz linear probe. The results showed: (1) After FSH treatment, the uterine and ovary of the donors began to enlarge, and the uterine wall began to thicken. Twenty-four hours later, 2-3mm (in diameter) small ovarian follicle began to appear as anichoic area, and grew larger and larger. After superovulation treatment, the 3-4d was the optimum period to monitor ovarian follicle growth. Before the operation of embryo collection, the corpus luteum could be scanned. The ultrasonogram of ovarian follicle was shown as a small anichoic area, while theultrasonogram of corpus buteum was shown as a hypoechonic area with some small echo bright dots. (2) After the treatment of estrus synchronization, the uterine and ovary of the recipients enlarged slowly. 1-2 anichoic areas of ovarian follicle could be seen when the estrus symptom was very apparent. A few recipient, long-strip anichoic area could be seen in uterine as uterine milk. (3) After embryo transfer, pregnancy recipient could scan 1cm (in diameter) of gestational sac within 20d. and the hyperechoic dumpling of embryo in the gestational sac was viewed around 30 d. The pulse of embryo heart was seen around 35 d. The optimum period for estimating the number of embryo is around 30-40d.3. Application of ultrasonographic monitoring in the producing process of embryo transfer in eweThe application was carried out in 9 farms of goats or sheep. The results indicated: (1) All goats or shee... |
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