Embryo Transplantation in Cattle

Fourteen true repeat breeders with entirely normal oestrous cyclicity more than 1 year after calving and 14 control donor cows were superovulated with PMSG (2000 i.u.) and flushed non-surgically 6–8 days after the superovulatory heat. The superovulatory response was identical for the 2 groups such as assessed by the number of corpora lutea (9.4 ± 1.8 C.L. per repeat breeder and 9.1 ± 1.5 per control cow), occurrence of ovarian overstimulation (polycysts), presence of a non-countable amount of corpora lutea, negative outcome of the flushings and the number of recovered embryos (5.8 ± 1.0 embryos per repeat breeder and 6.0 ± 1.8 embryos per control cow). The most pronounced difference between the 2 categories of animals was related to the fertilization rate of embryos. In the repeat breeder group only 2.4 embryos per cow or 41 % were fertilized, whereas the control animals attained a fertilization rate of 4.9 embryos or 82 %. Since most factors liable to interfere with the fertilization process were identical for both groups (age, breed, nutritional and management conditions, semen quality, dose, AI-technician e.g.), it is believed that intraovarian, follicular, or follicular-dynamic conditions were responsible for producing a high proportion of non-fertilizable oocytes.     

Cyclic AMP Affects Oocyte Maturation and Embryo Development in Prepubertal and Adult Cattle

High cAMP levels during in vitro maturation (IVM) have been related to improved blastocyst yields. Here, we employed the cAMP/cGMP modulators, forskolin, IBMX, and cilostamide, during IVM to unravel the role of high cAMP in early embryonic development produced from prepubertal and adult bovine oocytes. Oocytes were collected via transvaginal aspiration and randomly assigned to three experimental groups: TCM24 (24h IVM/control), cAMP30 (2h pre-IVM (forskolin-IBMX), 30h IVM-cilostamide), and DMSO30 (Dimethyl Sulfoxide/vehicle control). After IVM, oocytes were fertilized in vitro and zygotes were cultured in vitro to blastocysts. Meiotic progression, cAMP levels, mRNA abundance of selected genes and DNA methylation were evaluated in oocytes. Blastocysts were used for gene expression or DNA methylation analyses. Blastocysts from the cAMP30 groups were transferred to recipients. The cAMP elevation delayed meiotic progression, but developmental rates were not increased. In immature oocytes, mRNA abundance of PRKACA was higher for cAMP30 protocol and no differences were found for PDE3A, SMAD2, ZAR1, PRDX1 and SLC2A8. EGR1 gene was up-regulated in prepubertal cAMP30 immature oocytes and down-regulated in blastocysts from all in vitro treatments. A similar gene expression profile was observed for DNMT3b, BCL2L1, PRDX1 and SLC2A8 in blastocysts. Satellite DNA methylation profiles were different between prepubertal and adult oocytes and blastocysts derived from the TCM24 and DMSO30 groups. Blastocysts obtained from prepubertal and adult oocytes in the cAMP30 treatment displayed normal methylation profiles and produced offspring. These data indicate that cAMP regulates IVM in prepubertal and adult oocytes in a similar manner, with impact on the establishment of epigenetic marks and acquisition of full developmental competency.     

Factors Affecting Electro－Fusion and Electro－Activation In Serial Nuclear Transplantation In Goat（Carpa hircus） Embryo

ＦａｃｔｏｒｓＡｆｆｅｃｔｉｎｇＥｌｅｃｔｒｏ－ＦｕｓｉｏｎａｎｄＥｌｅｃｔｒｏ－ＡｃｔｉｖａｔｉｏｎＩｎＳｅｒｉａｌＮｕｃｌｅａｒＴｒａｎｓｐｌａｎｔａｔｉｏｎＩｎＧｏａｔ（Ｃａｒｐａｈｉｒｃｕｓ）ＥｍｂｒｙｏＷＡＮＧＹｕ－ｇｅ（王玉阁）;ＺＯＵＸ...     

无创胚胎染色体筛查技术在单囊胚冻胚复苏移植中的应用价值及其活产结局的因素分析

摘要 目的：探讨无创胚胎染色体筛查技术（NICS）在单囊胚冻胚复苏移植中的应用价值,分析影响活产结局的因素。方法：回顾性分析2019年1月至2021年12月我院收治的197例行单囊胚冻胚复苏移植患者的临床资料,53例行NICS检查且检测结果提示囊胚染色体拷贝数正常（NICS组）,26例NICS检测结果异常予以排除,118例未接受NICS检测（非NICS组）。收集临床资料并追踪妊娠结局,根据妊娠结局将患者分为活产组（75例）和非活产组（96例）,采用单因素及多因素Logistic回归分析影响单囊胚冻胚复苏移植活产的因素。结果：NICS组活产率高于非NICS组（P＜0.05）。单因素分析显示活产组女方年龄小于非活产组（P＜0.05）,基础卵泡雌激素（FSH）水平、常规试管婴儿（IVF）周期≥2个低于非活产组（P＜0.05）,优质胚胎数、移植日子宫内膜厚度和NICS检查比例、发育成囊胚时间为D5比例高于非活产组（P＜0.05）。多因素logistic回归分析显示女方年龄偏大、发育成囊胚时间为D6是影响单囊胚冻胚复苏移植活产的危险因素（P＜0.05）,NICS检查是其保护因素（P＜0.05）。结论：NICS筛查胎儿染色体异常可提高单囊胚冻胚复苏移植活产率,产妇高龄和囊胚发育速度过慢是影响活产的主要危险因素。在单囊胚冻胚复苏移植前有必要进行NICS检查,并尽量选择D5囊胚以提高活产率。     

血清孕酮水平检测在克隆胚胎移植受体牛的筛选及妊娠诊断中的应用

目的:孕酮(progesterone,P4)作为一种生殖激素,在牛的发情期和妊娠期呈规律性变化,且在妊娠的建立和维持过程中发挥着重要作用。拟应用孕酮浓度测定辅助人工观察筛选克隆胚胎移植受体牛并监测其整个妊娠过程。方法:通过对自然配种牛不同生殖阶段血液中孕酮水平的分析,建立其在发情初期、妊娠期孕酮浓度的变化规律,以此为依据辅助人工观察筛选适合胚胎移植的受体牛。同时将在体外培养7天后的体细胞核移植重构囊胚移植到所筛选出的同期发情的受体牛子宫内,并应用孕酮测定监测其妊娠状态。实验结果:(1)运用孕酮检测筛选克隆胚胎移植受体牛时,当孕酮浓度在发情第0天和第5天分别为≤0.64nmol/L和2～8nmol/L时,适宜作为胚胎移植受体牛,根据此筛选指标能够排除50%左右假发情牛。(2)运用孕酮检测较传统的人工观察方法,胚胎移植的克隆牛出生率提高了7.1倍。结论:运用牛血清孕酮检测方法能有效提高母牛生理周期判断的准确性,有利于选择合适的胚胎移植受体牛,既能实时、有效地监测怀孕受体牛的妊娠状态,又避免了靠人工观察受体牛返情、流产时的人为疏漏和误判,有效地提高受体牛的利用率,提高克隆牛的生产效率,并能推广应用于畜牧行业牛的生产繁育中。     

胚胎胸腺移植配合蛇毒抗癌素治疗晚期肝癌

目的探讨生物效应调节剂,联合蛇毒制剂治疗晚期肝癌近期疗效。方法采用人胚胸腺组织或细胞移植方法,配合口服蛇毒抗癌素胶囊和（或）腹腔内注射蛇毒抗癌素注射液（以下简称治疗组）与５－Ｆｕ、ＭＭＣ及ＦＴ－２０７三联（以下简称对照组）对晚期肝癌进行随机分组治疗,通过对临床症状改善、免疫功能变化以及生存期长短等项目观察判断疗效。结果对晚期肝癌治疗,治疗组疗效优于对照组,也优于单纯应用胸腺移植治疗晚期肝癌的治疗效果。结论人胚胸腺组织或细胞移植及蛇毒抗癌素胶囊或其注射液抗癌效果是确切的,联合应用比二者单用效果更佳。     

Oxytetragyclines in Cattle

Pharmacokinetics of oxytetracycline (OTC) were studied in 4 cows after administration of either a conventional (OTC-C) or a long-acting (OTC-LA) preparation. After intravenous administration of OTG-G the elimination half-life for OTG was found to be 6 h. Intramuscular injection of OTC-C and OTC-LA resulted in almost identical plasma concentrations of OTC with peak values after 6–8 h. For both preparations the bioavailability after i.m. administration was 100 % and about 60 % of the dose was excreted in the urine during the first week. Plasma concentrations above 0.5 μg/ml were with both preparations maintained for approximately 60 h, indicating no retard effect of OTC-LA as compared to OTC-C.     

Embryo recovery in swine

Embryos were surgically recovered 63 times from 13 purebred donor sows for an average of 4.8 times per donor. Recoveries were completed at three or six week intervals. An average of 15.6 transferable embryos were collected per surgery. Based on these limited observations it would appear that multiple surgical embryo recoveries may be completed on a specific donor at three and/or six week intervals without impairing future production.     

胚胎分割的研究进展

近二十年来 ,通过分割哺乳动物的早期胚胎来人工产生遗传上完全相同的同卵双胎或多胎动物 ,在绵羊、牛、小鼠、大鼠、马、兔、猪等哺乳动物中已广为开展〔１～１４〕。为生产上提供了具有优良品种（产肉、产奶量高等）的动物 ,同时 ,还给发育遗传学、生理学等领域提供了进行科学研究的宝贵材料。所谓胚胎分割系指用人工方法将一个植入前胚胎分割成两个或多个部分 ,每一部分移植后可发育成一个正常个体。早在１９５９年,Ｔａｒｋｏｗｓｋｉ〔１５〕发现一半卵裂球已被破坏的２ -细胞小鼠胚胎可以发育成囊胚 ,并出生了小鼠。其研究结果表明 :…     

家猫的胚胎工程

家猫是惟一一种没有被列为珍稀或濒危的猫科动物。通过家猫的胚胎工程研究,对保护其它濒危猫科物种有重要的借鉴意义。本文描述了家猫的一般生殖特点,着床前的胚胎在体内的发育概况;综述了近年来对家猫的超数排卵,卵母细胞的体外成熟,体外受精,胚胎的体外培养,胚胎移植,冷冻保存和胚胎克隆等方面的研究进展。