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本研究旨在从配种次数、配种时间以及促排卵药物的使用3个方面对后备母猪同期排卵-定时输精技术方案进行优化。将后备母猪随机分成6组：(1)自然发情对照组：母猪自然发情、配种;(2)简式定时输精组：使用烯丙孕素性周期同步化后母猪自然发情配种;(3)传统定时输精组：母猪性周期同步化后,经过孕马血清促性腺激素和戈那瑞林处理使得卵泡发育和排卵同步化,无需查情,固定时间输精;(4)两点式查情定时输精组：在传统定时输精的基础上增加了注射促排卵药物时和配种后24 h 2个查情、配种时间点;(5)诱导发情促排实时输精组：性周期和卵泡发育同步化后,母猪发情时注射戈那瑞林促排卵,实时输精;(6)诱导发情实时输精组：母猪性周期和卵泡发育同步化处理后,实时输精。使用B超监测各组母猪卵泡发育和排卵情况,评价不同程序对母猪发情时间、排卵集中度、卵泡囊肿和繁殖性能的影响。结果显示：与简式定时输精组相比,注射外源促性腺激素改变了卵泡生长速度和排卵时间,缩短了最后一次饲喂烯丙孕素到发情的间隔时间,但是并没有改变发情-排卵间隔时间和排卵前卵泡大小。诱导发情促排实时输精组母猪妊娠率（93.52%vs 76.85%）和分娩率（8... 相似文献
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随着畜牧业集约化、规模化发展,定时输精(Timed Artificial Insemination,TAI)技术已经成为家畜繁殖管理中的一项重要的实用技术,对实现家畜高效集中配种和提高生产力具有重要意义。本文介绍了家畜的繁殖调控规律,针对如何通过外源激素人为调控家畜生殖激素水平来实施定时输精做一综述,以促性腺激素释放激素法和前列腺素法作为家畜同步发情排卵的主要处理方法,详述了不同家畜品种定时输精的程序,剖析了家畜卵泡同步发育、黄体退化和排卵时间等影响家畜繁殖性能的主要因素,为实际生产中定时输精技术的应用提供借鉴和参考。 相似文献
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Tenhagen BA 《DTW. Deutsche tier?rztliche Wochenschrift》2005,112(4):136-141
This review describes factors that affect conception rate after synchronization of ovulation and timed artificial insemination. Intervals of 7 days between GnRH and PGF2alpha, 48 hours to the second GnRH treatment and a further 16 to 20 hours to the timed insemination have been proven to be most effective. Conception rates (CR) increase as lactation progresses up to 100 days in milk. Primiparous cows have higher CR than older cows. Anovular cows at the start of the synchronization protocols have poor CR. These are highest for cows started in early dioestrus. While poor body condition and some post partum and post insemination health disorders have negative effects on the CR, a significant effect of postpartum chronic endometritis could not be demonstrated. High milk yield was also not shown to have a negative effect on CR in almost all studies, while the negative effect of heat stress on fertility is also found in Ovsynch cows. However, the negative effects of high milk yields and heat stress on AI submission rates are overcome by the timed insemination protocol. 相似文献
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为了提高当年产犊母牦牛的发情率,我们对选定的120头怀孕母牦牛进行补饲,同时在犊牛产后3个月对犊牛进行隔离断奶,补饲试验于2010年3月初开始：100头母牦牛随机分为两组,试验组Ⅰ 50头母牦牛隔离断奶后进行同期发情和定时授精处理;Ⅱ组50头母牦牛隔离断乳.不进行同期发情处理,发情母牛进行人工授精。人工授精冻精液为荷斯坦和野牦牛冻精。配种45d后进行怀孕诊断。Ⅰ组发情39头,发情率为78%（39/50）,怀孕34头妊娠率为68%（34/50）;Ⅱ组发情31头,发情率为62%（31/50）,怀孕27头,妊娠率为54%（27/50）。相同草场放牧50头适配母牦牛作为对照。对照组母牛和犊牛不进行隔离和短期断乳;对照组发情率为12%（6/50）,妊娠率为6.32%（3/50）。试验结果表明,通过对带犊的母牦牛实施隔离断奶,能够明显提高当年产犊母牦牛的发情率和妊娠率。 相似文献
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[目的]为探讨同期发情—定时输精技术对云南省文山州母牛繁殖性能的影响,建立适宜于南方肉牛品种改良的轻简推广实用技术程序。[方法]通过肉牛同期发情—定时输精技术程序在文山州广南、砚山、富宁三县的应用效果作比较。[结果]结果表明,使用该技术程序后三县肉牛平均同期发情率为93.24%,平均受胎率达80.94%,应用效果良好;母牛体况对发情效果影响较大,有待提高母牛饲养管理水平。[结论]同期发情—定时输精技术对提高母牛受胎率的效果明显,值得在我国南方肉牛养殖业中大力推广。 相似文献
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羊同期发情及人工授精技术的生产应用 总被引：1，自引：0，他引：1
羊同期发情和人工授精技术是在生产中同时应用的配套技术。针对生产中应用羊同期发情技术同期发情率和受胎率参差不齐的实际情况,介绍孕激素栓＋孕马血清促性腺素（PMSG）＋氯前列烯醇（PG）羊同期发情方法,并按照技术应用操作顺序,详细介绍了同期发情及人工授精的具体技术细节,并对影响羊同期发情和人工授精技术应用效果的因素进行了分析,同时针对生产中容易出现的问题,提出了根据羊体况及场管理条件应用同期发情技术的建议。 相似文献
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An economic model concerning the value of using prostaglandin (PG) in dairy cows with nondetected estrus was developed. Considering numerous and varied assumptions, it was more profitable to treat cows with PG and to breed the cows at a detected estrus than it was not to treat the cows and to wait to breed the cows at a detected estrus. Generally, using timed artificial insemination, it was also more profitable to breed PG-treated cows than it was not to use PG. However, timed insemination was less profitable than was breeding PG-treated cows by artificial insemination at a detected estrus. 相似文献
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Hiers EA Barthle CR Dahms MK Portillo GE Bridges GA Rae DO Thatcher WW Yelich JV 《Journal of animal science》2003,81(4):830-835
Nonlactating Bos indicus x Bos taurus cows were used in three herds to determine the efficacy of different PGF2alpha treatments in combination with GnRH and melengestrol acetate (MGA) for a timed artificial insemination protocol. The start of the experiment was designated as d 0, at which time cows were assigned a body condition score and received 100 microg of GnRH. Cows were fed MGA (0.5 x mg x cow(-1) x d(-1)) on d 1 to 7. On d 7, cows received either a single injection of PGF2alpha (Lutalyse sterile solution; 25 mg; n = 297), a single injection of cloprostenol sodium (Estrumate; 500 microg; n = 297), or half the recommended dose of PGF2alpha (12.5 mg; n = 275) on d 7 and 8. On d 10, all cows were artificially inseminated and received 100 microg of GnRH. Pregnancy rates to the timed artificial insemination (39%) were not affected by treatment, herd, or treatment x herd. There was an effect (P < 0.01) of artificial insemination sire on timed artificial insemination pregnancy rate for one herd, but not the other two herds. Herd influenced (P < 0.05) 30-d pregnancy rates, but there were no treatment or treatment x herd effects as 72.3% of the cows became pregnant during the first 30 d of the breeding season. Results indicate that the type of PGF2alpha treatment administered 7 d after GnRH did not influence timed artificial insemination pregnancy rates in nonlactating Bos indicus x Bos taurus cows. 相似文献
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Marcos G. Colazo Reuben J. Mapletoft 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(8):772-780
This is a review of the physiology and endocrinology of the estrous cycle and how ovarian physiology can be manipulated and controlled for timed artificial insemination (TAI) in beef and dairy cattle. Estrus detection is required for artificial insemination (AI), but it is done poorly in dairy cattle and it is difficult in beef cattle. Protocols that synchronize follicle growth, corpus luteum regression and ovulation, allowing for TAI, result in improved reproductive performance, because all animals are inseminated whether they show estrus or not. As result, TAI programs have become an integral part of reproductive management in many dairy herds and offer beef producers the opportunity to incorporate AI into their herds. Gonadotropin-releasing hormone-based protocols are commonly used in North America for estrus synchronization as part of a TAI program. Protocols that increase pregnancy rates in lactating dairy cows and suckling beef cows have been developed. Protocols that improve pregnancy rates in heifers, acyclic beef cows, and resynchronized lactating dairy cows are also discussed. 相似文献
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Tenhagen BA Drillich M Heuwieser W 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2000,47(10):577-584
The effect of two insemination policies after synchronization of oestrus on reproductive performance in two groups of cows was investigated. Oestrus was synchronized by two treatments with prostaglandin F2 alpha (PGF2 alpha) at a 14-day interval. Cows in Group 1 (n = 234) were inseminated twice on appointment 66 and 90 h after the second treatment. Cows in Group 2 (n = 222) were intensively watched for signs of oestrus after the synchronization protocol and inseminated on observed oestrus. Cows with abnormal discharge after synchronization were excluded from breeding and inseminated later during the study period. Service rate within 1 week after synchronization was higher in Group 1 than in Group 2 (89.3 versus 67.1%). Conception rates on first service did not differ between groups (33.2 versus 30.0%). Days to first service and days open were shorter in Group 1 (P < 0.05). The number of cows culled for infertility did not differ between the groups. Endometritis 14-20 days post-partum decreased the percentage of cows pregnant at the end of the study period in both groups but did not have a significant effect on conception rates and days open. It is concluded that additional inseminations required in the timed artificial insemination protocol were economically justified by the reduction in days open in comparison with insemination on observed oestrus after synchronization. 相似文献
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Recent Developments in Oestrous Synchronization of Postpartum Dairy Cows with and without Ovarian Disorders 总被引：1，自引：0，他引：1
This report reviews the most recent developments in prostaglandin‐based oestrous synchronization programmes for postpartum dairy cows and addresses the efficiency of controlled breeding protocols based on such developments for cows with abnormal ovarian conditions. A double prostaglandin protocol applied 11–14 days apart seems to be capable of bringing most cows to oestrus. Because of varying oestrus onset times, improved conception rates are obtained following artificial insemination (AI) at detected oestrus rather than fixed‐time AI in prostaglandin‐treated cows. The administration of oestradiol or human chorionic gonadotrophin, or both these hormones, after prostaglandin treatment, improves the synchrony of oestrus yet does not enhance the conception rate. Progesterone‐based treatments for oestrous synchronization are considered the most appropriate for non‐cyclic or anoestrous postpartum dairy cows; prostaglandin alone being ineffective because of the absence of a mature corpus luteum in these cows. Improved oestrus synchrony and fertility rate have been reported using short‐term progesterone treatment regimes (7–9 days) with or without oestradiol benzoate combined with the use of a luteolytic agent given 1 day before, or at the time of, progesterone withdrawal. The ovulation synchronization (Ovsynch) protocol, based on the use of gonadotrophin releasing hormone and prostaglandin, was developed to coordinate follicular recruitment, CL regression and the time of ovulation. This protocol allows fixed time insemination and has proved effective in improving reproductive management in postpartum dairy cows. However, timed AI following Ovsynch seems to have no beneficial effects in heifers, because of an inconsistent follicle wave pattern, and in anoestrous cows, given their lack of prostaglandin responsive CL. To date, there are several prostaglandin based, fixed‐time insemination oestrous synchronization protocols for use in early postpartum dairy cows with ovarian disorders such as ovarian cysts and acyclicity. 相似文献