导　　师： 齐长明

学科专业： 090603

授予学位： 博士

作　　者： ;

机构地区： 中国农业大学

摘　　要： 羊胚胎移植是一项先进的繁殖技术,主要通过超数排卵、同期发情、采卵、检胚和移胚等技术处理实现“借腹怀胎”的目标。但因其技术环节多且环环相扣,一环脱节即全盘失败,故生产上出现问题较多、成功率不高。B超可在无痛苦、无损伤的情况下观察组织器官的超声切面图像。笔者采用这项诊断技术在羊胚胎移植各技术环节中进行监测,试图减少各环节中出现问题的几率,从而提高羊胚胎移植的成功率和经济效益。 1、母羊生殖器官的超声解剖 通过活体B超检测和屠宰对比观察,对母羊的阴道、子宫、卵巢及其周同组织器官做了详细的研究。结果表明:用3.5MHz扇扫探头作体表探查时的最佳位置是在股内侧、乳房后上侧方的少毛区,亦称鼠蹊部。用5.0MHz线阵探头经直肠探查时羊取自然站立保定,掏除直肠内宿粪后用消毒剂润滑过的长柄探头缓缓插入肛门,探头探测面朝下,并作45度角扫查,即可依次显示阴道、子宫颈、膀胱、子宫角和卵巢的声像图。在膀胱液性暗区前下方清晰可见子宫和卵巢为中等强度的同声结构,其包膜周边回声界限明显。强同声带声影的耻骨联合可作为盆腔和腹腔的分界线。其声像图结果经术中B超探查和水浴B超探查所证实。 2、羊胚胎移植模拟实验与生产实验及其B超监测技术 首先用奶山羊和小尾寒羊做胚胎移植模拟实验,而后在一个波尔山羊场和一个无角多赛特绵羊场做生产实验,初步掌握了羊胚胎移植技术及其B超监测技术。供体羊用FSH递减法做超数排卵处理;受体羊用孕酮阴道栓和PMSG做同期发情处理,处理后第6天分别采朋子宫角手术法冲胚和移胚。处理过程中均采用5.0MHz线阵探头经直肠B超监测。结果表明:①供体羊在超排处理后子宫开始增大,子宫壁增厚;卵巢持续增大,处理后24h在卵巢外周开始出现直径2-3mm的小卵泡液性暗区,并随时间推移而慢慢增大;卵泡发育的最佳监测时间为超排处理后的第3-4d,在声像图上可大致数清发育卵泡数量;冲胚前可监测到黄体形成。卵泡声像图表现为液性暗区,黄体声像图表现为夹杂有小回声光点的实质暗区,个别中央仍保留少量液性暗区。②受体同期发情处理后子宫增大,子宫壁增厚,卵巢缓慢增大。至发情表现旺盛时,卵巢上可监测到1-2个卵泡液性暗区,个别可见子宫腔内有少量长条状子宫乳液性回声带。③怀孕受体移胚20d即可监测到直径1cm左右的孕囊。30d左右可监测到孕囊液性暗区中胚节的强同声光点,35d左右可见胎心搏动。胎数鉴定的最佳时间为35-45d。 3、羊胚胎移植生产中的B超监测 在9个进行羊胚胎移植生产的羊场中实施了B超监测。结果表明:①选择供、受体前的B超普查可排除已孕羊、淘汰生殖道异常羊,从而带来直接经济效益,同时可提高胚胎移植成功率。在9个羊场917例普查统计中,准备用作供、受体的母羊已怀孕的占32.57/%,有生殖道疾病的占0.87/%,两项合计33.44/%。生殖道疾病包括子宫蓄脓、卵巢囊肿、输卵管积液、阴道积液等。②供体羊超排处理后3-5d可监测剑发育卵泡,据此可术前预测排卵数,估测采胚数。在3个羊场中对13只供体的监测统计为:B超监测卵泡数:回收胚胎数=142:133。③受体早孕鉴定与胚胎发育监测可及时掌握受体移胚后的妊娠状况。移胚后20-40d即可确诊妊娠羊,鉴定怀胎数。对5个羊场257例的统计表明,早孕监测准确率达100/%。④供体冲胚后及受体产后卵巢、子宫机能恢复状况的监测可提高供、受体的再利用率。B超监测尚可用于受体同期发情状况及公羊睾丸发育状况监测等。 4、羊胚胎移植及其B超监测参考图谱创建 经实验研究和生产实践,笔者将收集的羊胚胎移植图片和B超监测的声像图编辑成参考图谱,配以文字说明。相信对相关教学、科研和生产实践有一定的参考价值和指导意义。 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 the ultrasonogram 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

关 键 词： 羊 胚胎移植 超 声像图 监测技术

分 类 号： [S826]

领　　域： [农业科学] [农业科学]