黑安格斯母牛同期发情与受胎效果研究

宁夏泾源县2016年从澳大利亚引进的黑安格斯母牛群中,部分母牛不发情或发情不明显,导致长期不孕。2017年2-6月期间,对上述母牛进行了同期发情处理和冻配。同期发情方法为氯前列烯醇法和氯前列烯醇戈那瑞林法2种,结果表明,氯前列烯醇法(n=114)的同期发情率为82.42%,情期受胎率为78.72%,后者(n=267)的同期发情率为87.64%,情期受胎率为81.62%。氯前列烯醇戈那瑞林法的同期发情率和情期受胎率均高于氯前列烯醇法。本次试验不仅试验示范应用了规模化肉牛群的同期发情技术,而且解决了大量繁殖母牛的不孕难题,效果显著。     

氯前列烯醇诱导黄牛同期发情效果试验

氯前列烯醇是PGF2α的类似物,在目前常用的PGF2α及其类似物中,其活性最高。本试验应用氯前列烯醇对农牧民分散饲养的母牛进行同期发情效果观察。结果表明在24~72 h内92%的母牛发情,经直肠检查发情母牛排卵率为86%,情期受胎率为62%。说明氯前列烯醇对诱导母牛同期发情处理效果显著。     

氯前列烯醇控制黄牛同期发情及定时输精的研究初报

于黄牛发情季节应用国产氯前列烯醇 2次处理黄牛具有明显的同期发情效果 ,96小时内母牛同期发情率可达 80 %～ 92 .5% ,母牛于第 2次药物处理发情后发情率、卵泡发育率无明显差异 ,3mg氯前列烯醇剂量的人工配种情期受胎率与自然发情情期配种受胎率相比差异显著     

利用同期发情技术提高肉牛受胎率的研究

利用氯前列烯醇2次注射法在8家牛场228头黑安格斯繁殖母牛群中实施了同期发情处理,共发情166头,平均同期发情率72.81%,发情母牛全部进行了冻配,第一情期受胎率平均为74.70%,试验取得了良好效果,彻底解决了牛场空怀母牛的难题。     

氯前列烯醇控制受体黄牛同期发情试验

氯前列烯醇为我国新合成的高效畜用前列腺素F2α类似物 ,具有用量小、生物活性强、价格低等特点 ,对黄牛的功能性黄体 ,妊娠黄体 ,持久黄体等具有明显的溶解作用 ,调节黄牛的同期发情。注射氯前列烯醇到母牛发情平均间隔时间为 5 0 .5± 7.0h ,处理后周期发情的受体牛 ,冻胚移植成功率为 38.8% ,可代替 15甲基PGF2α使用。     

用氯前列烯醇对鲁北白山羊进行同期发情处理效果的观察

应用氯前列烯醇对鲁北白山羊进行同期发情处理,结果表明:采取氯前列烯醇处理空怀母羊588只,发情371只,同期发情率达63.10%,说明用氯前列烯醇对鲁北白山羊进行同期发情处理是成功的.     

采用氯前列烯醇对牛进行同期发情冻配效果好

在石阡县高魁、大岩两村用氯前列烯醇注射空怀健康的黄牛(86头)、水牛(46头)共132头母牛进行同期发情和冻配试验.结果表明:0～8 d发情牛共122头,同期发情率为92.42%(122/132),在2～6d发情的占总发情数的92.62%,有卵泡发育的母牛占发情母牛数的55%(22/40);冻配第一情期受胎率为43.59%(51/117),第二情期受胎率为60%(27/45).     

两种阴道栓诱导非繁殖季节山羊同期发情试验研究

利用氯前列烯醇(PG)、孕酮阴道栓对山羊进行同期发情处理,0~72h同期发情率平均为88.0%,其中PGF2α组为88.9%,孕酮栓组为87.5%,PG组与孕酮栓组无显著差异(P>0.05);处理羊发情时间,PG组主要集中于注射后的24~48h,发情率为80.6%,孕酮栓组主要集中于撤栓后的0~48h,发情率为84.7%;孕酮栓处理方法对处于非繁殖季节和繁殖季节的羊均可获得很好的同期效果,而PG处理方法只对处于繁殖季节的羊有效。     

几种山区牧场母牛发情调控技术方案的筛选

试验在山区牧场选择149头母牛进行。分为6组：（1）甲孕酮（MAP）＋孕马血清促性腺激素（PMSG）；2复合孕酮＋米非司＋PMSG；（3）MAP＋PMSG＋复合孕酮；（4）复合孕酮＋黄体酮＋PMSG；（5）黄体酮＋氯前列烯醇；（6）单独氯前列烯醇。试验结果，本试验6组处理对山区母牛发情及受胎率均有明显的影响，以第2组的效果为最好（P〈0．05），而第6组单独注射氯前列烯醇0．4mg处理，母牛的受胎率为0％。不同剂量PMSG多次处理表现出不同的效果。第1组与第2组比较，以较高剂量PMSG处理的为好（P〈0．05），对乏情母牛进行诱导发情，亦以较高剂量（500IU）PMSG处理的为好。     

氯前列烯醇诱导奶牛同期发情试验

应用氯前列烯醇对3组84头荷斯坦奶牛进行诱导同期发情,结果表明:用氯前列烯醇诱导奶牛同期发情是成功的;用氯前列烯醇处理2次的奶牛,比用氯前列烯醇处理1次的奶牛,其同期发情率、受胎率明显提高;同时,氯前列烯醇对奶牛持久黄体也有很好的治疗作用。     

非繁殖季节母驴诱导发情、排卵效果的研究

[目的]研究前列腺素F2α（PGF2α）、孕马血清促性腺激素（PMSG）、人绒毛膜促性腺激素（hCG）3种激素在不同处理方案下对内蒙古通辽地区乏情期母驴卵泡生长情况、排卵率、发情率、受胎率与妊娠率的影响。[方法]将50头2～6岁、体重接近、体况良好、处于乏情期的母驴随机分为A、B、C、D4组,其中D组为未使用任何激素的空白对照组。首先,采用PGF2α、PMSG进行诱导发情试验,对A、B、C3组母驴注射2mL／头PGF2α,连续处理5d,第6天对A、B组母驴分别注射PMSG 1000IU,头和500IU,头;C组不做PMSG处理。诱导发情后将A、B组再细分为A1、A2和B1、B2组,当A1、B1、C3组中母驴卵泡直径大于35mm时注射hCG（总量1500IU）进行诱导排卵;A2、B2不做hCG处理,由卵泡自然发育至排卵。对所有诱导发情后有发情表现的母驴进行自然本交。同时,在试验期间利用直肠检查和B超检查对母驴的卵巢发育进行监测。『结果]c组发情率为30％,经PGF2α处理第5天时卵巢黄体基本全部消退;A组和B组的发情率分别为93．33％和86．66％,二者差异不大,但均明显高于C组。A1、B1最终的排卵率为100％和77．78％,而A2和B2的排卵率为60．00％和50．00％。A,组受胎率和妊娠率最高,分别达到了88．89％和80．00％,其次是B,组分别为66．67％和60．00％,B2、C2组的受胎率和妊娠率都较低,D组虽然有1头母驴发情,但配种后未妊娠。[结论]单独使用PGF2α对非繁殖季节母驴诱导发情效果不明显,但其对消除母驴黄体有明显作用;PGF2α与PMSG联用对诱导乏情母驴发情效果较好。使用PGF2α与PMSG对处于乏情期的母驴诱导发情后,注射hCG对母驴卵巢上优势卵泡具有明显的促进排卵作用,能加快优势卵泡的排卵,且明显提高母驴的排卵率。该试验确定的最佳方案为：注射0．2mgPGF2α连续处理5d,第6天注射PMSG 500lU,当优势卵泡直径达35mm时注射hCG 1500lU,排卵后配种。     

Effect of GnRH pretreatment on reproductive performance of postpartum suckled beef cows following synchronization of estrus using GnRH and PGF2alpha

The effect of GnRH pretreatment on estrus detection rate, precision of estrus, and reproductive performance of postpartum beef cows synchronized to estrus using GnRH and PGF2alpha was evaluated. In Exp. 1, Angus cows (n = 87) were randomly assigned by parity, postpartum interval, and body condition score (BCS) to receive either 1) GnRH on d -7 and PGF2alpha on d 0 (GP) or 2) the GP treatment and an additional injection of GnRH on d -16 (GGP). Estrus detection and AI were conducted twice daily from d -3 to d 3. At 72 h after PGF2alpha, all animals not previously detected in estrus were bred by AI and received a concurrent injection of GnRH (TAI). Synchronized pregnancy rates were numerically increased (P = 0.15) in cows treated with GGP (55%) compared with those on the GP treatment (44%). In Exp. 2, 1,276 spring-calving, suckled beef cows in nine herds were randomized to treatments as described for Exp. 1, except that the initial GnRH injection for the GGP treatment was administered on d -14. Herd affected all indicators of reproductive performance (P < 0.05). The percentage of animals detected in estrus prematurely (d -3 to d 0; 7%) was not affected by treatment. Estrus response rate was influenced by postpartum interval (< 60 vs > or = 60; 61 vs 73%; P < 0.01) and a three-way interaction of parity, BCS, and treatment (P < 0.01). Within animals with a BCS > or = 5.5, the GGP treatment tended to increase the detection of estrus in primiparous cows (GP vs GGP; 76 vs 91%; P = 0.11) and decrease detection in multiparous cows (GP vs GGP; 78 vs 72%; P < 0.10). However, because conception rate to TAI in animals with a BCS > or = 5.5 was greater (P < 0.05) in the GGP than in the GP group (28 vs 8%, respectively), this interaction was interpreted to represent a shift in interval to estrus induced by the GGP treatment, rather than a reduction in the synchronization of ovarian function. Conception rates of animals inseminated to an observed estrus did not differ among treatments (P = 0.15). Synchronized pregnancy rate tended (P = 0.06) to be greater in GGP- (53%) than in GP-treated animals (47%). In conclusion, pretreatment with GnRH tended to increase pregnancy rates during a 6-d synchronization period, primarily through enhanced conception rates of cows bred by TAI. In contrast to our hypothesis, GnRH pretreatment did not increase the percentage of animals detected in estrus or the precision of estrus expression.     

氯前列醇诱导夏河牦牛同期发情辅助繁殖

[目的]研究探讨氯前列醇诱导牦牛同期发情的效果。[方法]选择夏河县桑科种羊场母牦牛为试验牛,采用氯前列醇注射液诱导牦牛同期发情。通过统计阶段发情率及产犊率来判断生殖激素不同处理方式对牦牛辅助繁殖的影响。[结果]首次氯前列醇注射液肌注2 mL处理后,牦牛发情率及产犊率大于第2次氯前列醇注射液肌注3.2 mL处理及第3次氯前列醇注射液肌注3.2 mL处理。[结论]通过氯前列醇处理牦牛同期发情,提高首次处理的发情率可有效提高整体产犊率,生殖激素调控藏区牦牛同期发情来提高牦牛繁育率。     

提高青年牦母牛繁殖性能的试验

33头3.5岁进入初情期的青年牦母牛采用生殖激素处理后,发情率达到69.70%,繁殖率达到57.58%;166头对照青年牦母牛的发情率为63.86%,繁殖率为22.89%;试验组比对照组发情率提高5.84百分点,繁殖率提高34.69个百分点(P<0.05)。采用PG-CL FSH和PG-CL LHRH-A3两种不同激素处理方案,PG-CL FSH处理组的发情率高于PG-CL LHRH-A3处理,两种处理的繁殖率基本相同。     

非繁殖季节奶山羊同期发情处理效果研究

为了探讨两种同期发清处理方法和不同年龄阶段对非繁殖季节奶山羊同期发情效果的影响,选用12∽15月龄初产奶山羊和4∽5胎经产奶山羊分为两组,采用孕激素耳栓埋植和阴道栓塞两种处理,并辅以肌注PMSG及PG-CL、E2,每组试验重复2次.结果显示：孕激素耳栓埋植法和阴道栓塞法两种同期发情处理方法处理初产组奶山羊总发情率分别达到87.5％和100.0％,经产组分别达到77.8％和83.3％,均无显著差异（P＞0.05）.但两种方法0∽24 h内的同期发情率初产组阴道栓法平均为94.1％,耳栓法平均为37.5％,差异显著（P＜0.05）,经产组阴道栓法平均为61.1％,耳栓法平均为44.4％,差异亦显著（P＜0.05）;无论初产、经产组奶山羊阴道栓法处理0∽24 h内的同期发情率（分别为94.1％、61.1％）显著高于24∽36 h发情率（分别为5.9％、22.2％）（P＜0.05）.用阴道栓同一种方法处理初产和经产奶山羊,初产组24 h的同期发情率（86.7％）显著高于经产组（60.0％）（P＜0.05）.阴道栓法处理同期发情效果优于耳栓法,初产奶山羊的同期发情效果优于经产奶山羊.     

半血野牦牛超数排卵研究

为提高高寒环境下牦牛的繁殖能力,选用青海大通种牛场半血野牦牛(n=12),进行了同期发情和超数排卵试验。结果表明,用氯前列烯醇处理后的发情率为(12/12)100%,用药后25~36 h之间发情的占(3/12)25%、37~48 h之间发情的占(9/12)75%。用中科院动物所生产FSH8.4 mg、FSH8.8 mg、PVP包埋FSH8.5 mg和新西兰产FSH15 mg进行超数排卵。结果表明,用中科院动物所生产FSH8.8mg超数排卵处理后,回收胚胎17枚,有效胚胎12枚,头均4枚;用新西兰产FSH15 mg超数排卵后,回收胚胎2枚,有效胚胎2枚,头均0.7枚,其他两组没有得到胚胎。     

Factors affecting pregnancy rate to estrous synchronization and fixed-time artificial insemination in beef cattle

Application of AI in extensive beef cattle production would be facilitated by protocols that effectively synchronize ovarian follicular development and ovulation to enable fixed-time AI (TAI). The objectives were to determine whether use of a controlled internal drug release (CIDR) device to administer progesterone in a GnRH-based estrous synchronization protocol would optimize blood progesterone concentrations, improve synchronization of follicular development and estrus, and increase pregnancy rates to TAI in beef cows. Beef cows (n = 1,240) in 6 locations within the US Meat Animal Research Center received 1 of 2 treatments: 1)?an injection of GnRH [100 μg intramuscularly (i.m.)] followed by PGF(2α) (PGF; 25 mg i.m.) 7 d later (CO-Synch), or 2) CO-Synch plus a CIDR during the 7 d between GnRH and PGF injections (CO-Synch + CIDR). Cows received TAI and GnRH (100 μg i.m.) at 60 h after PGF. Progesterone was measured by RIA in blood samples collected 2 wk before and at initiation of treatment (d 0) and at PGF injection (d 7). Estrous behavior was monitored by Estrotect Heat Detectors. Pregnancy was diagnosed by ultrasonography 72 to 77 d after TAI. Plasma progesterone concentrations did not differ (P > 0.10) between synchronization protocols at first GnRH injection (d 0), but progesterone was greater (P < 0.01) at PGF injection (d 7) in cows receiving CO-Synch + CIDR vs. CO-Synch as a result of fewer CIDR-treated cows having progesterone ≤1 ng/mL at PGF (10.7 vs. 29.6%, respectively). A greater (P < 0.01) proportion of CO-Synch + CIDR vs. CO-Synch cows were detected in estrus within 60 h after PGF (66.7 vs. 57.8 ± 2.6%, respectively) and a greater (P < 0.01) proportion were pregnant to TAI (54.6 vs. 44.3 ± 2.6%, respectively). For both synchronization protocols, cows expressing estrus within 60 h before TAI had a greater pregnancy rate than cows without estrus. For cows with plasma progesterone ≤1 ng/mL at PGF injection, CO-Synch + CIDR increased pregnancy rate (65.2 ± 5.9 vs. 30.8 ± 3.4% with vs. without CIDR), whereas pregnancy rates did not differ (P > 0.10) between protocols (52.1 ± 2.1 vs. 50.0 ± 2.4%, respectively) when progesterone was >1 ng/mL (treatment × progesterone; P < 0.01). Inclusion of a CIDR in the synchronization protocol increased plasma progesterone concentration, proportion of cows detected in estrus, and pregnancy rate; however, the increase in pregnancy rate from inclusion of the CIDR was primarily in cows with decreasing or low endogenous progesterone secretion during treatment.     

产后无发情和亚发情母牦牛激素诱导发情试验

选择怀孕母牦牛84头,在生产前后1个月进行补饲,其中40头在产后当年发情季节进行激素诱导发情试验,44头作对照;另选择60头自然生产的产后母牦牛在发情季节进行单纯的激素诱导发情试验,60头作对照.激素诱导发情方法是0 d注射氯前列烯醇0.2 mg,7 d后注射促黄体素释放激素A3 25 μg,连续3 d;在0和7 d进行直肠检查和血样采取,血样进行孕酮测定;测定处理时母牦牛卵巢状态,观察母牦牛发情配种受孕情况.结果显示,通过直肠检查和血浆孕酮测定,发现无发情状态的产后母牦牛占产后牦牛的63.33%和65%,亚发情的产后母牦牛占产后牦牛的36.67%和35%.采用氯前列烯醇和促性腺激素释放激素处理方案进行诱导发情,26.67%的产后母牦牛在处理后出现了发情;对怀孕母牦牛在围产期进行补饲,产后母牦牛在发情季节采用氯前列烯醇和促性腺激素释放激素诱导发情,有45.45%的产后母牦牛恢复了发情,而只补饲不进行激素诱导发情的母牦牛只有20%的母牦牛出现了发情;通过孕酮测定发现2组中激素诱导发情成功的母牦牛中,有68.18%和72%是处于亚发情状态的母牦牛.结果表明,氯前列烯醇和促性腺激素释放激素进行诱导发情的处理方案适合于产后亚发情状态的母牦牛.     

Effect of P.G. 600 on the timing of ovulation in gilts treated with altrenogest

We previously reported that ovulation rate, but not pregnancy rate or litter size at d 30 after mating, was enhanced by treatment with P.G. 600 (400 IU of PMSG and 200 IU of hCG, Intervet America, Inc., Millsboro, DE) in gilts fed the orally active progestin, altrenogest (Matrix, Intervet America, Inc.) to synchronize estrus. We hypothesized that in addition to increasing ovulation rate, P.G. 600 may have altered the timing of ovulation. Therefore, mating gilts 12 and 24 h after first detection of estrus, as is common in the swine industry, may not have been the optimal breeding regimen, and as a consequence, pregnancy rate and litter size were not altered. The objective of the present study was to determine the effect of P.G. 600 on the timing of ovulation in gilts treated with altrenogest. Randomly cycling, crossbred gilts (5.5 mo old, 117 kg BW, and 14.7 mm of backfat) were fed a diet containing altrenogest (15 mg/d) for 18 d. Twenty-four hours after altrenogest withdrawal, gilts received i.m. injections of P.G. 600 (n = 25) or saline (n = 25). Gilts were checked for estrus at 8-h intervals. After first detection of estrus, transrectal ultrasonography was performed at 8-h intervals to determine the time of ovulation. Gilts were killed 9 to 11 d after the onset of estrus to determine ovulation rate. All gilts displayed estrus by 7 d after treatment with P.G. 600 or saline. Compared with saline, P.G. 600 increased (P = 0.07) ovulation rate (14.8 vs. 17.5, respectively; SE = 1.1). The intervals from injection to estrus (110.9 vs. 98.4; SE = 2.7 h; P < 0.01) and injection to ovulation (141.9 vs. 128.6; SE = 3.2 h; P < 0.01) were greater in gilts treated with saline than in gilts treated with P.G. 600. Duration of estrus (54.4 vs. 53.7; SE = 2.5 h), the estrus-to-ovulation interval (30.2 vs. 31.7; SE = 2.2 h), and the time of ovulation as a percentage of estrus duration (55.8 vs. 57.5; SE = 3.0%) did not differ for the P.G. 600 and saline-injected gilts, respectively. In summary, P.G. 600 advanced the onset of estrus and ovulation following termination of altrenogest treatment and increased ovulation rate; however, treatment of gilts with P.G. 600 had no effect on the timing of ovulation relative to the onset of estrus.     

带犊牦牛同期发情与自然发情繁殖效果比较

[目的]为了对比带犊牦牛同期发情与自然发情繁殖效果的差异,作者根据实施的科研项目进行了两组试验,以便为甘南牦牛产业高质量发展提供参考资料。[方法]于繁殖季节在试验组母牦牛阴道内放置“孕激素阴道栓”并肌肉注射“氯前列稀醇”(CIDR+PG)诱发牦牛集中发情。[结果]结果表明,甘南牦牛在当年生产后,通过犊牛统一断奶,改变营养供给,产后3个月试验组和对照组母牦牛自然发情率分别为8%和19.2%。试验组母牦牛应用“放置孕激素阴道栓+肌肉注射氯前列稀醇”方法诱导发情后,总发情率达89.1%。试验组带犊母牦牛激素处理后受胎率为89.1%,对照组母牦牛自然发情率较低,自然交配后受胎率为100%。试验组和对照组母牦牛繁殖率、犊牛成活率分别为86.9%和19.2%、97.6%和100%,试验组犊牛的平均初生重、断奶重、6月龄重分别比对照组高1.51 kg、2.37 kg、3.28 kg,经差异显著性检验,试验组犊牛相关年龄段体重与对照组犊牛对应指标相比,初生体重差异显著(P<0.05),断奶重和6月龄体重差异极显著(P<0.01)。[结论]使用外源性激素诱发带犊母牦牛当年集中发情,母牦牛当年...