人工授精+胚胎移植(AI+ET)法诱发肉牛双胎的试验研究

应用AI ET法分别对3组试验牛处理,人工诱导生产肉牛双胎,双胎率达60.8%(79/130),产犊率147.7%(192/130).其中试验组Ⅱ(自然发情后AI ET)双胎率达66%(33/50),产犊率150%(45/30),显著提高了母牛的繁殖率.     

胚胎移植诱导肉牛双胎应用研究

用超数排卵方法对西门塔尔牛与本地黄牛杂交的母牛进行处理,获胚胎69枚,其中可用胚胎(A、B级)45枚,移植妊娠率66.7%,诱导双胎率达到40%.     

安格斯肉牛胚胎移植试验

应用胚胎移植技术，对当地9头母牛进行了安格斯肉牛胚胎的移植试验，结果受胎4头，受胎率为44．4％。     

肉牛冷冻胚胎移植试验

通过对平凉市45头秦川血系受体牛移植红安格斯、利木辛、夏洛来、皮埃蒙特等品种肉牛冷冻胚胎的结果分析,证明要提高胚胎移植妊娠率,就要选择健康的受体牛,作好受体母牛补饲工作,处理好受体母牛同期发情,认真观察发情,作好发情记录,准确移植。     

肉牛胚胎移植研究

采用严格筛选受体牛和以个体为核心的措施,将5枚德国黄牛和比利时蓝牛的冷冻囊胚移植给本地牛,移植成功率达到60%,取得了较好移植效果。     

上杭县肉牛可视化人工授精技术试验

由于传统直肠把握人工授精技术需要操作人员把手伸进牛直肠,给人“脏”的感觉,且操作难度较大,让很多想学习技术的人望而却步。我们整合集成现代技术,用发情排卵测定仪对母牛进行发情鉴定,用可视化输精枪进行输精,用B超进行怀孕测定,在上杭县蓝顺养殖有限公司开展了牛细管冷冻精液可视化人工授精集成试验,取得了成功。     

体外受精和胚胎移植技术在肉牛双胎生产中的应用研究进展

牛繁殖效率低导致的犊牛生产成本高已成为制约肉牛产业发展的重要因素。利用体外受精和胚胎移植（IVF-ET）技术进行双犊生产是提高肉牛繁殖效率的有效途径。IVF-ET技术通过一系列复杂的胚胎工程操作过程,已经获得多种家畜。在我国,牛IVF-ET技术应用于生产实践还存在技术与经济效益方面的问题,但作为一种获得肉牛双犊的生产技术,IVF-ET有潜力改变肉牛产业的生产现状。本文概述了牛IVF-ET各个技术环节在国内外的发展现状,以及目前存在的问题和发展方向,进一步探讨了该技术应用与肉牛双胎生产实践的可能性,为提高肉牛生产效益提供新的策略。     

肉牛胚胎移植技术应用研究

1998～ 2 0 0 0年通过对 13头西门塔尔牛FSH -PG法超排处理 ,超排有效头数 10头 ,获可用胚 7 8枚 /头。探索了在不同营养条件下的移植妊娠率 ,说明注射营养药对妊娠率有著影响 (P <0 0 1)。比较了经产牛与育成牛的移植妊娠率 ,育成牛显著高于经产牛 (P <0 0 1) ,分析了 1次PG与 2次PG注射法对受体牛同期发情的影响 ,表明 2次PG注射法高于 1次注射法 (P <0 0 5 )。对冻胚与鲜胚移植效果进行了比较 ,并对影响移植效果的因素进行了分析 ,从而对大规模的实施牛的ET计划提供了科学参考依据     

安格斯肉牛胚胎移植试验报告

〔目的〕为探讨和研究安格斯肉牛胚胎移植在武威市的应用前景,指导我市的高档肉牛养殖,〔方法〕我们以西杂母牛为受体,进行了10头安格斯双胚、6头输精后7天移植单胚、389头单胚、10头移植前注射黄体酮和促黄体素a3共4项试验研究。〔结果〕双胚移植受孕2头,产犊结果都为单胎;移植加输精0头、单胚移植受孕率为16.8%、注射激素受孕率为10%。〔结论〕使用体内胚胎,加强妊娠牛的饲养管理,可能会提高产双犊几率,在以后生产中可以推广和应用;输精后牛各项激素和生殖受孕环境发生变化不适合于胚胎移植,在生产中利用不大;胚胎移植同步注射黄体酮和促黄体素a3在提高牛体外胚胎妊娠率的利用中作用不大。     

A new alternative for embryo transfer and artificial insemination in mares: ultrasound-guided intrauterine injection

A transvaginal ultrasound-guided intrauterine injection (IUI) technique was developed for embryo transfer and for injection of small quantities of sperm in mares. The target area of a horn was positioned by transrectal manipulation against the wall of the vaginal fornix over the face of a transvaginal transducer. A needle with a catheter containing the embryo or semen was inserted through the needle guide of the transducer into the uterine lumen. The tips of the needle and catheter, the movement of the catheter in the uterine lumen, and the ejection of fluid was monitored on the ultrasound screen. Pregnancy rate 15 days after ovulation for the IUI embryo transfer technique (30/39, 77%) was similar to the pregnancy rate for transcervical (TC) embryo transfer (30/38, 79%). The pregnancy rate for IUI insemination of 20 × 10⁶ progressively motile sperm into the tip of the uterine horn ipsilateral to ovulation was 5/10 (50%). Results indicated that the IUI approach is a viable alternative for embryo transfer. Results also supported the potential of IUI for insemination of low numbers of sperm, but more extensive studies with various doses of sperm are needed.     

肉牛品改冷配技术体系中的计算机管理系统

在我国南方很多省份,肉牛主要以散养为主,导致母牛发情后常不能及时冷配,而冷配员却又闲着的现状,从而使母牛配种率低、存栏母牛有下降趋势。针对此情况,研发了肉牛冷配软件(软著登字2009SR11157,软件产品登记测试(2009-12-S2701)),对发情(乏情)预报、发情控制以及冷配员日常工作等方面进行计算机管理。冷配员通过规范地记录日常工作数据,逐步输入计算机,利用软件制定的日常工作计划实施冷配。结果表明:(1)对发情正常但漏配的母牛,通过软件准确预报有效黄体期,实施1次PG同期发情技术,同期发情率高于直肠检查组;(2)对乏情母牛,既实现了不通过直肠检查尽早发现、及时治疗缩短产犊间隔的目的,又获得了较高的受胎率;(3)规范了母牛的繁殖记录、提高了数据利用效率,并促进了牛繁殖数据记录的持续开展。     

Conception rate,uterine infection and embryo quality after artificial insemination and natural breeding with a stallion carrier of Pseudomonas aeruginosa: a case report

Background

Pseudomonas aeruginosa may cause venereal disease and infertility in horses. A Pseudomonas aeruginosa - carrier stallion, often unresponsive to artificial vagina collection, was used to naturally breed mares. Semen collected from the same stallion was also used to perform artificial inseminations. Pregnancy rates, embryo quality and incidence of uterine infection were compared between inseminated or naturally-bred mares.

Methods

P. aeruginosa was isolated from swabbing of the penis, prepuce and distal urethra of the stallion. Before being bred or inseminated, clitoral/vestibular samples were collected from all mares, and cultured for isolation of P. aeruginosa. At the first observed estrus, endometrial swabs were also collected. All mares subjected to natural mating (NS) were re-evaluated for P.aeruginosa by culture of clitoral and endometrial swabs. Artificial inseminations (AI) were performed either with fresh-extended semen (11 AI/7 mares) or frozen semen (10 AI/7 mares). The stallion was also used to breed 3 mares (4 services). For embryo collection, 2 mares were inseminated with fresh-extended semen (1 AI/mare), and 2 additional mares were inseminated with frozen semen (2 AI/mare). Two mares were naturally-bred with a total of 9 services, for embryo collection. All mares were examined after AI or natural service (NS), for uterine pathologies. Embryo recoveries were attempted passing a catheter with inflatable cuff connected to a sterile flexible 2-way flushing catheter, through the cervix. Flushed media was recovered into an Em-Con filter, and embryos searched using a stereoscope. Embryos were graded from 1 (excellent) to 4 (degenerated/dead).

Results

Pregnancy rates obtained after NS was 50% per cycle. However, more than half of the NS resulted in uterine disease, while uterine pathology was seen only in 22% of the time following AI. Half of the mares bred by NS got positive to P. aeruginosa. Percentage of embryo recovery rates was identical after AI or NS (66.7%). The 4 embryos recovered after AI were classified as Grade 1, while after NS only 2 out of the 6 recovered embryos were Grade 1.

Conclusion

a) there was no evidence of reduced fertilization after AI or NS, b) a numerically higher incidence of uterine disease was noticed after NS, c) venereal transmission of P. aeruginosa after NS was confirmed, d) a lower percentage of G1 embryos may be obtained after NS. Overall, the data supports the indication for P. aeruginosa-carrier stallions to be bred by AI rather than by NS, and raises the possibility that P. aeruginosa may affect embryo quality.     

人工授精技术在辽宁绒山羊改良工作中的重要作用

人工授精技术在辽宁绒山羊产业中的应用,不仅使优秀种用公羊的利用效率明显提高,同时也极大地促进了我国个体的低产绒山羊的改良工作,可提高绒山羊养殖的经济效益,实现科研推广部门和养殖户利益双赢,具有非常大的发展前景。     

浅谈猪精液保存在人工授精中的发展与展望

在世界上主要的猪肉生产国中,猪人工授精(AI)技术的应用率在90%以上。尽管猪冷冻精液技术在不断进步,但由于其效率不高,在猪场实际生产中并不多见使用。在猪人工授精技术中,液态精液是目前应用最广泛的精液,与传统的牛冷冻精液不同,其独特的精子微胶囊保护膜技术,可以对猪精子进行更加完善的液态保存,因此液态精液是目前猪人工授精使用的主要方式。文章综述了猪精液保存技术在人工授精中的应用,并展望了今后的发展方向,为人工授精技术助力恢复生猪生产提供参考。     

猪人工授精技术在我国北方地区的应用

猪人工授精技术是当前养猪业生产中的一个重要环节,在我国北方地区,尤其是内蒙古地区,猪人工授精技术还没有普及。为了适应养猪业发展步伐,在内蒙古西部地区的养猪场建立了采精站,针对北方冬季寒冷的特点,探索在采精室安置暖气和空调,授精时用护腕包裹授精瓶等前提下应用猪人工授精技术,达到促进我国北方地区养猪业健康良性快速发展的目的。     

Effects of acrosomal conditions of frozen-thawed spermatozoa on the results of artificial insemination in Japanese Black cattle

The purposes of this study were to examine the relationship between male artificial insemination (AI) fertility and sperm acrosomal conditions assessed by new and conventional staining techniques and to identify possible reproductive dysfunctions causing low conception rates in AI using frozen-thawed spermatozoa with poor acrosomal conditions in Japanese Black bulls. We investigated individual differences among bulls in the results concerning (1) acrosomal conditions of frozen-thawed spermatozoa as assessed by not merely peanut agglutinin-lectin staining (a conventional staining technique) but also immunostaining of acrosomal tyrosine-phosphorylated proteins (a new staining technique), (2) routine AI using frozen-thawed spermatozoa as assessed by pregnancy diagnosis, (3) in vivo fertilization of frozen-thawed spermatozoa and early development of fertilized eggs as assessed by superovulation/AI-embryo collection tests and (4) in vitro fertilization of frozen-thawed spermatozoa with oocytes. The percentages of frozen-thawed spermatozoa with normal acrosomal conditions assessed by the abovementioned staining techniques were significantly correlated with the conception rates of routine AI, rates of transferable embryos in superovulation/AI-embryo collection tests and in vitro fertilization rates. These results are consistent with new suggestions that the distribution of acrosomal tyrosine-phosphorylated proteins as well as the acrosomal morphology of frozen-thawed spermatozoa are AI fertility-associated markers that are valid for the prediction of AI results and that low conception rates in AI using frozen-thawed spermatozoa with poor acrosomal conditions result from reproductive dysfunctions in the processes between sperm insemination into females and early embryo development, probably failed fertilization of frozen-thawed spermatozoa with oocytes.     

Reservoirs of Staphylococcus aureus in meat sheep and dairy cattle

The objective of the study was to investigate reservoirs and transmission of S. aureus in ewes and lambs in 3 meat sheep flocks. Repeated sampling of milk, teat skin, nasal- and vaginal mucous membranes was performed and samples were analysed for S. aureus. For comparison, samples were also collected from cows and young heifers in 3 dairy cattle herds. Selected isolates were compared by pulsed-field gel electrophoresis (PFGE). S. aureus was detected in 8 (1.5%) of 520 milk samples from ewes and in 38 (6.4%) of 588 milk samples from cows. From body site swabs, S. aureus was found in 394 (32.6%) of 1208 samples from sheep and in 67 (16.0%) of 420 samples from cattle. The proportion of S. aureus-positive nasal swabs from ewes and cows were 56.7% and 13.9%, respectively. From lambs, 58.2% of the nasal swabs were S. aureus-positive. In each flock, one S. aureus pulsotype predominated. Identical S. aureus pulsotypes were found in milk and from body sites. Paired S. aureus isolates from the nasal cavity of (i) ewes and their lambs, (ii) twins and (iii) from repeated swabs of individual ewes were compared by PFGE, and in the majority of cases the two isolates were identical. The results contribute new knowledge indicating frequent transmission of S. aureus between the dam and her lambs and within animals in a flock. In contrast to cattle, S. aureus is frequently present in the nose of sheep which may represent the primary reservoir of S. aureus in sheep flocks.     

Studies of gel with immobilized semen by intrauterine endoscopy post-artificial insemination

An extended lifespan of spermatozoa following artificial insemination (AI) can make the timing of insemination less critical, as previously demonstrated with immobilized spermatozoa that are gradually released from an alginate gel. The purpose was to examine the in vivo dissolution of SpermVital (SV) alginate gel over time by endoscopy and secondly to assess spermatozoa quality after incubation of the gel. In vivo endoscopy showed SV gel in the uterus 3, 6, 20 and 24 hr after AI, demonstrating the potential release of spermatozoa to the uterus during this period. In utero ex vivo incubation of the semen demonstrated that high motility and viability of sperm cells was sustained following overnight incubation.