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氯前列烯醇控制受体黄牛同期发情试验 总被引：2，自引：0，他引：2
应用氯前列烯醇对１０３头次经直肠检查确认有功能黄体的健康、未孕成件母牛进行周期发情处理，发情反应率为９５．１，从注射到发情平均间隔时间为５０．５ｈ，在３８－６２ｈ范围内发情母牛为８８．３，对７４头母牛注射氯前列烯醇后排卵及黄体形成情况进行观察，结果７２头排卵，其中８头没有形成功能黄体，占发情母牛１１．０％，氯前列烯醇处理的受体黄牛移植成功率与自然发情受体牛没有差别。 相似文献
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应用氯前列烯醇诱导山羊同期发情形成同期黄体暨冷冻胚胎移植试验报告 总被引：4，自引：0，他引：4
应用氯前列烯醇处理3～4周岁母山羊90只,诱导其同期发情进而形成同期黄体。试验结果显示,以接受试情羊爬跨为准,第一次用药后参试羊发情率达到86.7%;第二次用药后发情率达到97.8%。剖检结果表明,形成的黄体达到可移植胚胎水平的占92.3%。胚胎移植成功率69.4%。 相似文献
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文章对1997-2005年人工授精技术、2002年胚胎移植技术、同期发情技术在盈江县水牛生产中的应用效果进行了总结.结果1997-2005年盈江县应用水牛人工授精改良德宏水牛11 431头/次,受胎率50.81%;改良二品种杂交水牛660头/次,受胎率40.16%,德宏水牛的受胎率高于(P＞0.05)二品种杂交水牛,但差异不显著(P＞0.05);用国产氯前列烯醇(PG)0.6mg/头·次处理后,水牛的同期发情率经产水牛高于青年水牛,(P＞0.05),杂交水牛高于德宏水牛(P＞0.05),体重401～530kg水牛高于体重300～400 kg水牛(P＜0.05);发情明显水牛的可用率极显著高于发情不明显的水牛(P＜0.01).经超排所获4枚可用鲜胚分别移植3头受体,90 d检查时的妊娠率为33.33%,但最终未产犊. 相似文献
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为控制母牛适宜的产犊间隔(12～13个月),我们采用氯前列烯醇对乏情奶牛进行促情效果的实验。1材料和方法选择年龄4～8岁,中等膘情,产后120d以上不发情,直检未孕,卵巢上有黄体的黑白花奶牛为试验牛168例,按随机选择的方法进行分组实验:A组为子宫内投用氯前列烯醇药物;B组为肌肉注射氯前列烯醇药物。氯前列烯醇(0.2mg/支),上海市计划生育科学研究所研制,批号970318。2结果见表1,子宫内灌注氯前列烯醇0.2mg、0.3mg、0.4mg,发情有效头数差异不显著(p>0.05);肌肉注射氯前列烯醇0.2mg、0.4mg,发情有效头数差异显著(p<0.05);子宫内灌注给药0.2mg、… 相似文献
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153头健康经产中国荷斯坦牛分为3组，用3种方法进行同期发情处理。第1组注射1次氯前列烯醇；第2组注射2次氯前列烯醇；第3组注射促排3号－氯前例烯醇－促排3号。结果表明：第1，2，3组发情率分别为32．65％（16／49），45．59％（31／68）和91．30％（42／46），第3组发情率显著高于其它两组（P＜0．05）。 相似文献
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GnRH、PGF2α诱导奶牛同期发情效果的比较 总被引：6，自引：0，他引：6
同期发情处理是牛人工授精中的一项重要技术，不同的方法因不同的环境而产生不同的效果。本文就同期发情的不同方法进行了比较，以寻找适合本地环境的同期发情方案。153头健康经产的中国荷斯坦奶牛分为3个组，用3种不同的方法进行同期发情处理。第1组：注射1次氯前列烯醇；第2组：注射2次氯前列烯醇；第3组：注射促排3号－氯前列烯醇－促排3号。结果表明：第1组、第2组和第3组经不同的处理后，发情率分别为32.65%(16/49),45.59%(31/68)和91.30%（42/46），第3组的发情率分别显著高于其它两个组（P＜0.05）。结果提示促排3号－氯前列烯醇－促排3号可能是较适合中国荷斯坦奶牛的同期发情方案。 相似文献
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本试验选用276头高产中国荷斯坦牛为研究对象,其中120头初产奶牛和156头经产奶牛均表现为分娩期异常或产后期异常,如难产、胎衣不下、双胎难产、早产或子宫感染。试验牛被分为处理组与对照组。处理组在产后20d间隔811连续两次皮下注射氯前列烯醇（0.4mg/次）,对照组注射4．0mL灭菌生理盐水。然后观察其首次发情的时间、适合第一次人工授精的时间、首次授精妊娠率、150d妊娠率、产后的空怀天数、重复配种奶牛的比例和每头牛的授精次数。结果表明,产后应用前列腺素对产后首次发情的时间和产后首次人工授精的时间没有影响,但处理组奶牛首次人工授精的妊娠率明显升高,这在头胎牛更为明显;产后应用氯前列烯醇可明显减少平均授精次数、缩短产后空怀时间、增加产后150d泌乳奶牛的妊娠率、降低产犊后重复配种率。 相似文献
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氯前列烯醇治疗奶牛持久黄体上效果较好。笔者为找出最佳用药量和方法,特选择年龄4～8岁,中等膘情,产后120天以上不发情,直检未孕,卵巢上有黄体的黑白花奶牛为试验牛168例。按随机选择的方法分为两种处理,用氯前列烯醇分别子宫内投药以及肌肉注射。实验结果判断,以用药当天为0天,用药后1～6天内出现发情排卵的奶牛判为有效,用药后6天以上未出现发情,直检有黄体存在的奶牛判为无效。无效的奶牛12天后继续给药。催情效果:子宫内灌注氯前列烯醇0.2、0.3、0.4毫克组牛,发情有效头数分别为88.89%(32/36)、92.11%(35/38)和90.00%(27/30),差异不显… 相似文献
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M Garcia-Winder P E Lewis R W Bryner R D Baker E K Inskeep R L Butcher 《Journal of animal science》1988,66(8):1974-1981
Effects of age of cow and a norgestomet (N) implant on number of embryos and endocrine responses to induction of superovulation were studied in old (greater than 12 yr) and young (5 to 7 yr) lactating beef cows. Seventeen cows (8 old and 9 young) received a 6-mg N ear implant on d 4 or 5 of the cycle (d 0 = estrus); the remaining 17 cows (9 old and 8 young) served as untreated controls (C). All animals were treated with 38 mg of porcine follicle-stimulating hormone (FSH-P) in decreasing dosages over a 4.5-d period beginning on d 10 or 11. Regression of the corpus luteum was induced with injections of PGF2 alpha at 0800 and 2000 on d 4 of FSH-P treatment; implants were removed at the second injection of PGF2 alpha. Cows were inseminated artificially 12 and 24 h after onset of estrus. Embryos were collected on d 7 or 8 postinsemination. Blood samples were obtained daily at 0800 from 2 d prior to initiation of treatment with FSH-P until collection of embryos. An additional sample was collected each day at 2000, from the first injection of PGF2 alpha to 1 d after onset of estrus. Samples were assayed for luteinizing hormone (LH), progesterone (P4), follicle stimulating hormone (FSH) and estradiol-17 beta (E2). Total number of embryos plus ova recovered was lower (P less than .01) in N-treated (5.2 +/- 1.1) than in C-treated (10.6 +/- 1.6) cows.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Dejarnette JM Day ML House RB Wallace RA Marshall CE 《Journal of animal science》2001,79(7):1675-1682
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. 相似文献
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Two experiments were performed to evaluate the efficacy of a progestin-based estrus synchronization program that incorporated the use of estradiol at the initiation of progestin treatment and at 48 h after progestin withdrawal (Exp. 2). In Exp. 1, cyclic, lactating dairy cows (n = 112) were assigned to receive either 1 (1mg) or 2 (2mg) mg of estradiol benzoate via an i.m. injection on d -9 (d 0 = initiation of the breeding season). All cows received an intravaginal progesterone-releasing insert (IPI; CIDR-B) on d -9. On d -2, the IPI was withdrawn and all cows were administered 500 microg of cloprostenol sodium. Beginning on d 0, cows were bred by AI upon detection of estrus. Estrus was observed in similar proportions of cows in each treatment during the first 6 d of AI (90% across treatments), but the interval to estrus was shorter (P < .05) in 1mg (1.26 +/- .18 d) than in 2mg (1.77 +/- .18 d). Conception and pregnancy rates did not vary among treatments; however, cows in estrus on d 0 tended to be less fertile (P = .11) than those in estrus on d 1. In Exp. 2, 408 cyclic cows from three herds were assigned to receive either no synchrony treatment (Control, n = 214) or the treatments described in Exp. 1 (1mg, n = 100; 2mg, n = 94). Anestrous cows from all herds received an IPI from d -9 to -2 (n = 143; Anestrus). All cows in the 1mg, 2mg, and Anestrus groups, with the exception of those detected in estrus between d -1 and 0, also received 1 mg of estradiol benzoate on d 0. Greater than 90% of cows that received an IPI were in estrus between d -1 and 3, and 92.1% of cows in the Control group were in estrus by d 21. Conception rate to first service in 2mg (61.7%) was similar to Control (57.0%), tended to be higher (P = .06) than 1mg (49.0%), and was greater (P < .05) than Anestrus (39.9%). The mean day of conception was earlier (P < .05) in the 2mg (d 13.1 +/- 2.0) than the Control (d 23.2 +/- 1.6) and Anestrus (d 22.4 +/- 1.9) groups. Conception occurred earlier in 1mg (d 17.4 +/- 2.1) than in Control. The proportion of cows that were pregnant at the end of the breeding season tended (P = .09) to be greater in the 2mg and Anestrus groups. This regimen of estrus synchronization improved reproductive competence in cyclic cows and resulted in similar reproductive performance in anestrous cows and untreated cyclic cows inseminated at a spontaneous estrus. 相似文献
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The objective of this study was to determine whether an antiestrogen (enclomiphene) would shorten the interval to first estrus and conception in postpartum beef cows. Sixty postpartum Angus beef cows were stratified by age, body condition, and calving date and were randomly assigned to one of two treatment groups. Group 1 cows (n = 24) received three silastic implants, each containing 150 mg of enclomiphene, on d 20 postpartum. Implants were removed on d 30 postpartum. Group 2 cows (n = 28), received empty implants and served as controls. Cows were artificially inseminated at first detected estrus. Estrus detection and ovulation were further verified by increased serum progesterone. Concentrations and pulse frequencies of LH were determined from blood samples collected at 15-min intervals for 6 h on d 20, 25, 30, and 40 postpartum. Hypothalami and pituitaries were collected from four cows in each treatment group on d 30 postpartum and analyzed for concentrations of estradiol receptors. Concentrations of total and unoccupied hypothalamic and pituitary estradiol receptors were reduced by enclomiphene. Neither concentrations nor pulse frequencies of LH differed significantly between treatment groups on any of the 4 d. Days to first estrus did not differ (P greater than .05) between enclomiphene-treated (57 +/- 6; n = 24) and control (56 +/- 4; n = 28) cows. Days to conception did not differ between treated (81 +/- 9) and control (79 +/- 8) cows. The dose of enclomiphene used in this study reduced hypothalamic and pituitary estrogen receptors but did not alter secretion of LH or days to first estrus in the postpartum beef cow. 相似文献
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Effects of heat stress during pregnancy on postpartum reproductive changes in Holstein cows 总被引：1，自引：0，他引：1
Effects of heat stress during the last third of gestation on reproductive changes postpartum were studied in Holstein cows. Cows and heifers 160 to 190 d of gestation were assigned in June 1978 to shade (n = seven cows and two heifers) or no shade (n = eight cows and two heifers) management treatments. After parturition, all cows (n = 19) were moved to the milking herd and managed uniformly. On the day of calving and on each Monday, Wednesday and Friday thereafter until d 50 postpartum, jugular blood samples were collected. Beginning approximately 7 d postpartum, the reproductive tract of each cow was examined rectally after collection of blood samples. Estrus was monitored twice daily and cows were inseminated after d 45 postpartum. Prepartum heat stress increased 13,14-dihydro-15-keto-prostaglandin F2 alpha (PGFM) concentrations postpartum and increased the rate of uterine involution. Regardless of prepartum treatment, progesterone concentrations indicated that luteal phases had begun by d 12.4 +/- 1.3 postpartum, which was about 3 d before PGFM was basal. The first luteal phase lasted only 10.7 +/- .9 d. First estrus was not detected until d 32.3 +/- 4.8 postpartum. The previously gravid uterine horn had a negative effect on ovarian volume, diameter of the largest follicle and percentage of ovaries with a corpus luteum. However, prepartum heat stress attenuated this effect. This study indicates that heat stress prepartum had residual effects on postpartum reproductive changes, and that the previously gravid uterine horn exerted some control, which was attenuated by heat stress, over ovarian recrudescense. Even though heat stress prepartum affected sensitive measures of postpartum reproductive function, it did not alter days to first estrus, days open (102.3 +/- 13.1) or services/conception (2.5 +/- .3). 相似文献
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从美国引进高产奶牛性控雌性胚胎，在农村条件下，选择自然发情的黄牛作受体，移植合格受体牛648头。结果显示，自然发情黄牛924头中，经直肠检查合格受体牛648头，使用合格率为70．13％（648／924）；氯前列烯醇同期处理476头，使用合格率为36．13％（172／476），差异极显著（P〈0．01）。80～100d怀孕检查，自然发情移植成功率41．98％（272／648），同期发情移植成功率40．12％（69／172），差异不显著（P〉0．05）。自然发情黄牛不同黄体级别的移植成功率分别为：A级44．09％（41／93），B级42．43％（199／469），C级37．21％（32／86），差异不显著（P〉0．05）。单胚移植580头，移植成功率42．41％（242／580），双胚移植68头，移植成功率44．12％（30／68），差异不显著（P〉0．05）。正常胚胎单枚移植541头，移植成功率42．51％（230／541），裸胚单枚移植39头，移植成功率30．77％（12／39），裸胚比正常胚移植成功率低11．74％。怀孕牛已出生犊牛83头。其中母犊79头．公犊4头，母犊占95．18％，与自然发情的性比例（50％）相比较，差异极显著（P〈0．01）。 相似文献
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Postpartum anestrous interval in beef cows is a major factor contributing to reproductive failure during a defined breeding season. Our objectives were to determine the ability of a controlled internal drug-releasing device (CIDR, 1.9 g of progesterone), a normal dose of melengestrol acetate (MGA, 0.5 mg x cow(-1) x d(-1)), or a high dose of MGA (4.0 mg x cow(-1) x d(-1)) to induce ovulation and to eliminate short estrous cycles. Multiparous beef cows (n = 100) were equally assigned to one of four treatments: CIDR, normal MGA, high MGA, or control by age, days postpartum, body condition, and body weight. All cows were fed carrier (0.9072 kg x cow(-1) x d(-1)) with (normal MGA, 0.55 mg/kg; high MGA, 4.41 mg/kg) or without MGA for 7 d (d -6 to 0). On d -6, CIDR were inserted and then removed on d 0. Estrous behavior was monitored continuously from d -6 until 29 using HeatWatch electronic mount detectors. Blood was collected on d -13, and three times weekly from d -6 to 29. Treatment influenced (P = 0.03) the percentage of cows that were detected in standing estrus. Beginning on d 2, more CIDR-treated cows had exhibited standing estrus compared with high MGA-treated or control cows, but CIDR- and normal MGA-treated cows did not differ. The percentage of CIDR-treated cows that had ovulated was greater (P < 0.05) than the percentage of normal MGA-treated, high MGA-treated, or control cows beginning on d 4. The percentage of cows that exhibited standing estrus before the first postpartum ovulation (CIDR = 65%, normal MGA = 57%, high MGA = 35%, control = 30%) did not differ (P = 0.09) among treatments. Luteal life span following the first ovulation postpartum and the percentage of cows with a normal luteal life span (i.e., progesterone > 1 ng/mL for > or = 10 d) was greater (P < 0.01) in CIDR-treated cows (14.0 +/- 0.8 d; 20/20, 100%) compared with normal MGA-treated (6.2 +/- 1.0 d; 3/13, 23%), high MGA-treated (9.6 +/- 1.0 d; 8/14, 57%), or control cows (6.1 +/- 0.9 d; 4/17, 24%), and greater (P < 0.03) in high MGA-treated cows than in normal MGA-treated or control cows. In the present study, treatment of early postpartum suckled beef cows with CIDR induced ovulation and initiated estrous cycles with a normal luteal life span in more cows than did treatment with MGA. Treatment with MGA (normal or high dose) did not induce ovulation earlier than in control cows, but a high dose of MGA increased the percentage of cows with normal luteal life spans following the first ovulation postpartum. 相似文献
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Lemaster JW Yelich JV Kempfer JR Fullenwider JK Barnett CL Fanning MD Selph JF 《Journal of animal science》2001,79(2):309-316
Postpartum and lactating crossbred cows containing a percentage of Bos indicus breeding at three locations were studied to determine the efficacy of GnRH + PGF2alpha combinations for synchronization of estrus and(or) ovulation. Cows were equally distributed to each of three treatments by body condition score at the start of the experiment (d 0). All cows received 100 microg of GnRH on d 0 and 25 mg of PGF2alpha 7 d later. The three insemination protocols included 1) AI 12 h after exhibiting estrus during d 7 to 12 of the experiment (Select-Synch; n = 197); 2) timed-AI + 100 microg of GnRH on d 9 of the experiment (CO-Synch; n = 193); 3) AI 12 h after exhibiting estrus during d 7 to 10 of the experiment. Cows not exhibiting estrus by d 10 were timed-AI and injected with 100 microg of GnRH on d 10 of the experiment (Hybrid-Synch; n = 200). The percentage of cows exhibiting estrus during d 7 to 12 of the experiment was lower (P < 0.05) for CO-Synch (17.6%) cows than for Select-Synch or Hybrid-Synch (45.2 and 33.0%, respectively) cows, which did not differ (P > 0.05). For the Select-Synch and Hybrid-Synch cows that exhibited estrus during d 7 to 10 of the experiment and were artificially inseminated, conception rates were similar across treatments (50.5%). Pregnancy rates were greater (P < 0.01) for CO-Synch and Hybrid-Synch (31.0 and 35.5%, respectively) cows than for Select-Synch (20.8%) cows. A greater (P < 0.01) percentage of cycling cows became pregnant (34.5%) than noncycling cows (25.9%) across all treatments. The CO-Synch and Hybrid-Synch synchronization protocols resulted in greater pregnancy rates compared with the Select-Synch protocol in postpartum and lactating crossbred cows containing a percentage of Bos indicus breeding. 相似文献
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奶牛胚胎分割试验研究 总被引：8，自引：0，他引：8
简单分割7～8天奶牛胚胎59枚(117个半胚)。裸半胚成对移给59头奶牛或黄牛,80～90天有27头(45.8％)妊娠。最后24头受体产犊34头,半胚产犊率29.1％(34/117)。有10对双胎,双胎率41.7％(10/24)。比较在不同情况下—7天或8天;晚桑椹或囊胚期;透明带软化处理或不软化处理—分割的半胚,成对移植后受体妊娠率分别是40.0％和57.9％;35.7％和54.8％;48.6％和41.7％。半胚产犊率分别是26.6％和34.2％;23.6％和33.9％;30.0％和27.7％。均无显著差异(P>0.05)。分割优质胚胎得到最好的(35.7％)半胚产犊率。半胚在体外5小时内移植有较高(30.5％)的产犊率。试验探索了奶牛半胚移给远处分散的农户黄牛的可能性。11对奶牛半胚移给11头黄牛有6头(54.5％)妊娠。最后5头受体产下7头奶牛犊,两对同卵双胎。 相似文献