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为探讨促孕散治疗持久黄体的作用机理,本研究通过直肠检查结合B超直肠检查对持久黄体奶牛做出诊断后口服促孕散,应用B超每3 d对黄体直径、卵泡数量、卵巢长度、卵巢宽度、子宫角纵径和子宫颈纵径进行测量,并统计1次,与用药前进行对比。30头持久黄体奶牛口服促孕散后,治疗有效头数25头,有效率为83.3%。停药后第1天卵巢出现小卵泡和中等卵泡,停药后分别在第10和19天大卵泡数量最多,部分奶牛出现发情并排卵,与用药前卵巢相比,结果发现左、右侧卵巢长在停药后均降低,但差异不显著(P>0.05);左、右卵巢宽在停药后均降低,但差异不显著(P>0.05);子宫颈纵径和子宫角纵径均在停药后升高,但差异不显著(P>0.05)。结果表明,B超是诊断奶牛持久黄体的有效手段,中药促孕散对持久黄体奶牛卵巢和子宫形态等指标具有一定的影响,可以促进黄体的溶解。 相似文献
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《中国畜牧杂志》2020,(4)
本实验旨在探究孕酮缓释硅胶栓结合氯前列醇钠和促性腺激素释放激素(GnRH)类似物处理对母马同期发情和定时输精效果的影响。在繁殖季节,选取43头不同胎次的健康空怀腾冲母马,分为A、B组。A组(n=23)中第1、2、3胎次母马数量分别为6、10、7头,均肌注1 mL GnRH类似物记作第0天,第2天阴道内埋植阴道孕酮缓释硅胶栓,第8天肌肉注射4 mL氯前列醇钠,第11天取栓的同时再次肌肉注射4 mL氯前列醇钠,第12～16天B超检查卵泡发育状态。当卵泡直径到33 mm时,注射GnRH类似物1 mL,8 h后用低温保存的公马精液进行输精,输精后24 h和48 h检查母马排卵率,配种后15 d检查受胎率。B组(n=20)均为第2胎次,不做任何激素处理,在自然发情条件下进行B超检测和人工授精处理,记录其发情、排卵和受胎率。结果表明:A组在处理的第12～16天,86.95%的母马卵巢出现直径大于33mm的卵泡,一次输精后的情期受胎率为65.00%;B组在12～16 d内,20.00%的母马卵巢出现直径大于33mm的卵泡,情期受胎率为75.00%。本实验方案对前3胎次母马的发情同步率和怀孕率没有显著差异。因此,本实验处理方案可以使母马群在配种季节集中发情和配种,大大减少卵泡发育的检查时间和配种次数,并能获得较理想的受胎率。 相似文献
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奶牛生产中,因为早期黄体发育不全引起不孕的占相当的比例,尤其是饲料单一、缺乏运动的奶牛。这些母牛常表现微弱发情,直检卵泡发育缓慢,输精4～5d后仅能感觉到一个很小的黄体残迹,再后来,黄体发育不全不能形成妊娠黄体,导致奶牛不孕。1采用绒毛膜促性腺激素(hCG)如奶牛有发情症状,但发情症状不明显,此时易导致排卵延迟,早期黄体发育不全,可在发情后12～24h肌肉注射hCG1000～2000单位,在配种后4～5d肌肉注射hCG3000～5000单位。2采用垂体促黄体素(LH)奶牛发情经人工授精后,可分别在输精后第3、4、5d肌肉注射LH200单位。奶牛的早期黄体发… 相似文献
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应用LRH-A和黄体酮治疗奶牛不孕症36例 总被引：1，自引：0，他引：1
奶牛不孕症的类别繁多,病因也错综复杂。本文仅介绍排卵障碍引起的功能性不孕和胚胎早期死亡引起的屡配不孕。排卵障碍包括不排卵和排卵延迟,表现为久配不孕。不排卵的病牛一般具有正常的发情周期(平均21天),直检发情期卵泡能发育到最大体积,但不排卵,进而成熟的卯泡发生退化和闭锁,形成闭锁即泡。不排卵病因可能与卵巢促黄体激素(LH)分泌不足有关。排卵延迟的病牛发情正常,但发情 相似文献
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《中国牛业科学》2017,(1)
【目的】为了获得更多的纯种和牛,【方法】采用临床观察、直肠检查和B超检查筛选出114头荷斯坦牛作为受体牛,采用CIDR埋栓做同期发情,在发情后第7天用B型超声仪对受体牛黄体直径进行测量,对符合条件的受体牛进行胚胎移植,将不同黄体直径(corpus lutum diameter,CLD)分为3个组,分别为1≤CLD≤1.5、1.5CLD≤2.5和CLD2.5。在移植后第23天用B超做妊娠诊断,以便研究黄体直径对移植受胎率的影响。【结果】表明,选择114头牛做同期发情,发情率为96.5%(110/114);黄体直径1≤CLD≤1.5组、1.5CLD≤2.5组、CLD2.5组受胎率分别是44.44%(4/9)、45.95%(17/37)和42.11%(8/19),各组之间差异均不显著(P0.05)。【结论】说明黄体大小与胚胎移植受胎率没有直接相关性。 相似文献
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[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。 相似文献
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超数排卵(超排)的目的是获得最大数量的可移植胚胎,在传统的超排方案中,处理于发情周期的中期(排卵后8￣12天,等于发情后9￣13天),奶牛在超排前,需要通过直肠检查卵巢黄体的质量好坏才能确定是否选用。其一是增加了劳动强度;其二是一部分牛因排卵后没能形成好的黄体而未被利用,而且超排处理一般在产后60天进行,重复超排间隔时间延长到2个月、甚至半年以上,严重影响了高产奶牛的利用率,减少了可移植胚胎的数量。目前,我们采用通过控制卵泡波同期化方法,在奶牛发情后的任意1天,在不做发情检测的情况下,在供体牛阴道内放置CIDR(孕酮阴道硅胶… 相似文献
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选取发情正常、无生殖系统疾病、发情后未经配种就排红的荷斯坦奶牛38头,由技术人员做直肠检查,并做好排卵与未排卵的记录。参试牛无论排卵与否,均立即进行输精1次。在输精后2个月和4个月,分别进行1次妊娠检查,确诊受胎情况。结果表明,38头参试牛中,有9头尚未排卵,输精后受胎7头,受胎率为77.78%;已排卵的29头,输精后受胎1头,受胎率为3.45%。 相似文献
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The study was aimed to observe the variation and differences of corpus luteum of delayed ovulation cows after estrus.Based on the observation of clinical symptoms, rectal examination and diagnosis of B-ultrasound scanning, 8 delayed ovulation dairy cows with the variation (delayed ovulation group) and 5 healthy and normal dairy cows with estrus (control group) were selected, and the related indicators of the corpus luteum (diameter, area, perimeter and volume) were measured by B-ultrasound scanning.These luteal indicators were compared and analyzed further, and the luteal typical sonography obtained of the different stages were described.The results showed that the diameter, area, perimeter and volume during 7 to 15 d after estrus of the corpus luteum had no significant differences between delayed ovulation group and control group (P>0.05).However, on the 9th and 13th day after estrus, the luteal relevant indicators of delayed ovulation group cows (diameter, volume, area and perimeter) were greater than that of control group cows and less than normal dairy cows on the 11th day.There were no significant differences in diameter, area, circumference and volume of corpus luteum at the different stages after estrus between the delayed ovulation dairy cows and the normal ones. 相似文献
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Endocrine changes and ultrasonography of ovaries in suckled beef cows during resumption of postpartum estrous cycles 总被引：3，自引：0，他引：3
R C Perry L R Corah G H Kiracofe J S Stevenson W E Beal 《Journal of animal science》1991,69(6):2548-2555
Changes in follicular and luteal structures were assessed and concentrations of estradiol and progesterone were measured in 13 Hereford X Angus suckled beef cows during resumption of estrous cycles. Transrectal ultrasonography was used to monitor follicular size, ovulation, and formation and regression of the corpus luteum (CL). The interval from parturition to first postpartum ovulation (FO) was 82 +/- 4.7 d. Serum progesterone remained low before FO. One cow exhibited standing estrus, two cows showed other signs of estrus, and 10 displayed no signs of behavioral estrus preceding FO. All cows exhibited standing estrus before the second postpartum ovulation (SO). All cows had a short luteal phase after FO, with an average interval of 8.5 +/- .2 d between FO and SO. Concentrations of estradiol in serum during the 8 d preceding ovulation were similar before FO and SO. Maximal diameter of the preovulatory follicle was similar before FO and SO. However, the ovulatory follicle was larger in diameter at 2 d (P = .02) and 3 to 8 d (P less than .005) before FO than before SO. The time from detection until ovulation was less (P = .005) for the ovulatory follicle preceding SO than for the follicle associated with FO (8.5 vs 10.2 d, respectively, SE = .4). The second-largest follicle was larger (P less than .005) in diameter during the 8 d preceding the FO than before the SO. The difference in size between the ovulatory follicle and the second-largest follicle on the day before ovulation was greater (P less than .005) preceding SO than preceding FO (8.7 vs 6.6 mm, respectively, SE = .4).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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K Heinonen 《Acta veterinaria Scandinavica》1988,29(2):239-243
The reliability of clinical ovarian findings was assessed as an indicator of luteal function in primiparous dairy cows. The postpartum period of 103 cows following their first parturition was studied by thrice weekly rectal palpation of ovaries and whole milk progesterone assay from 1 week after parturition to the first insemination. The relationship between milk progesterone levels and 1101 ovarian findings was compared during the follicular phases, short luteal phases and during the early, mid and late thirds of normal luteal phases. The compatibility between elevated progesterone and palpable corpus luteum was 71%, and between low progesterone and lack of corpus luteum 77%. In 10% of all rectal examinations the finding was unspecified; i.e. the clinician could not differentiate between luteal and follicular activity. During the acyclic period prior to the initiation of luteal function, the proportion of false corpus luteum findings was 11%. The corpora lutea of the short oestrous cycles were more difficult to palpate than those of normal cycles. During early dioestrus the corpus luteum was significantly more difficult to palpate than during the rest of dioestrus. The percentage of unspecified findings was highest during early dioestrus.The paper discusses the reliability of rectal examination as a method of diagnosing cyclicity and of evaluating the responsiveness of a cow to prostaglandin treatment. 相似文献
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The present study aimed to know whether all cows have been showing declining fertility or only a proportion of cows are attributed to the declining fertility, and to describe factors affecting the level of fertility. A total of 131 cows calved from February 2005 to December 2007 in a dairy herd were examined. Fourteen cows were excluded from the study because of early culling. Of the remaining 117 cows, 47 (40%) conceived within 115 days postpartum after 1–3 artificial insemination (AI) (normal fertility cows), 42 (36%) conceived after 115 days postpartum following 1–3 AI or were culled after 1–2 (sub‐fertility cows/culled), and 28 (24%) were inseminated more than three times without detectable genital tract abnormalities (repeat breeders). Calving to conception interval in the normal fertility group was 72 + 3 days, while in the sub‐fertility/culled and repeat breeding groups the intervals were 170 + 8 and 259 + 16 days, respectively. Endometritis was the risk factor for sub‐fertility/culled (odds ratio (OR) = 3.76). Prolonged luteal phase (OR = 4.08), delayed first ovulation (OR = 6.02), and delayed corpus luteum formation after AI (OR = 8.55) were the risk factors for repeat breeding. In conclusion, 60% cows showed reduced fertility in a herd, while the other 40% had normal fertility. Uterine infection and some ovarian disorders contributed to reduced fertility. 相似文献
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Fernando LóPEZ-GATIUS Irene LóPEZ-HELGUERA Fabio DE RENSIS Irina GARCIA-ISPIERTO 《The Journal of reproduction and development》2015,61(5):465-471
This study compared the responses shown by lactating dairy cows to four different P4-based protocols for AI at estrus. Cows with no estrous signs 96 h after progesterone intravaginal device (PRID) removal were subjected to fixed-time AI (FTAI), and their data were also included in the study. In Experiment I, follicular/luteal and endometrial dynamics were assessed every 12 h from the beginning of treatment until AI. The estrous response was examined in Experiment II, and fertility was assessed in both experiments. The protocols consisted of a PRID fitted for five days, along with the administration of different combinations of gonadotropin releasing hormone (GnRH), equine chorionic gonadotropin and a single or double dose (24 h apart) of prostaglandin F2α. In Experiment I (40 cows), animals receiving GnRH at the start of treatment showed a significantly higher ovulation rate during the PRID insertion period while estrus was delayed. In Experiment II (351 cows),
according to the odds ratios, cows showing luteal activity at the time of treatment were less likely to show estrus than cows with no signs of luteal activity. Treatment affected the estrous response and the interval from PRID removal to estrus but did not affect conception rates 28–34 days post AI. Primiparous cows displayed a better estrous response than multiparous cows. Our findings reveal acceptable results of 5-day P4-based protocols for AI at estrus in high-producing dairy cows. Time from treatment to estrus emerged as a good guide for FTAI after a 5-day P4-based synchronization protocol. 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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O J Ginther 《Equine veterinary journal》1990,22(3):152-156
Prolonged luteal activity is one of the most formidable terminology challenges in mare reproductive biology. Prolonged luteal activity can be a result of persistence of an individual corpus luteum or the sequential development of luteal glands, each of which may have a normal life span. Luteal tissue can originate from an unovulated follicle or from an ovulation occurring during either follicular or luteal dominance. These complexities, together with ambiguous and inconsistent terminology, have resulted in confusion regarding those conditions which can be grouped broadly under the term prolonged luteal activity. Persistence of an individual corpus luteum can occur in association with severe damage to the endometrium resulting in loss of the uterine luteolytic mechanism. Spontaneous (no known uterine pathology) persistence of the corpus luteum from the follicular-phase ovulation has not been documented adequately as a clinical entity. The occurrence of ovulation towards the end of dioestrus may cause confusion about the origin of prolonged luteal activity. Such immature dioestrous corpora lutea may not respond to the release of uterine luteolysin, thereby leading to prolonged luteal activity even though the original corpus luteum regressed at the normal time. In the absence of critical monitoring of the corpus luteum (eg by ultrasound) the prolonged activity could be attributed erroneously to persistence of the corpus luteum from the follicular-phase ovulation. Pseudopregnancy is another confusing term that is sometimes used to describe persistence of the corpus luteum, especially when the luteal persistence is caused by embryonic loss after the embryo has blocked the uterine luteolytic mechanism.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Ordonez A Parkinson TJ Matthew C Holmes CW Miller RD Lopez-Villalobos N Burke J Brookes I 《New Zealand veterinary journal》2007,55(2):69-76
AIMS: To assess if raising concentrations of crude protein (CP) in pasture in spring by the frequent application of urea fertiliser would affect ovarian follicular dynamics, luteal function, onset of oestrus and reproductive performance of dairy cows under farming conditions in New Zealand. METHODS: Spring-calved dairy cows were grazed for 101 days in paddocks that were either not fertilised (Control; n=20) during the course of the study, or were fertilised with 40-50 kg nitrogen (N)/ha every 4-6 weeks (High-N; n=20). Similar generous pasture allowances were offered to both groups. Concentrations of CP in pasture, urea in serum and progesterone in milk were measured. Ovarian follicular and luteal dynamics were determined using ultrasonography. Oestrous behaviour and the number, time and outcome of inseminations were also recorded. RESULTS: Mean concentrations of CP in pasture and urea in serum was higher in the High-N than the Control group (25.2 vs 21.6 and 8.3 vs 5.4 mmol/L for CP and urea, respectively; p<0.001). Intervals between calving and first oestrus, first insemination and conception, the time of first emergence of a dominant follicle, milk progesterone concentration, and the diameter of the corpus luteum (CL) in the first luteal phase did not differ significantly between groups. The interval from calving to first ovulation tended (p=0.10) to be lower and the diameter of the dominant follicle of the oestrous cycle at which cows conceived was greater (p=0.02) in Control than High-N cows. CONCLUSIONS: The use of large amounts of urea fertiliser during spring and the consequent increases in concentrations of CP in pasture and urea in serum did not negatively affect any of the parameters of reproductive performance of pasture-fed dairy cows that were assessed in this study. 相似文献
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Toshiaki SUMIYOSHI Tomomi TANAKA Hideo KAMOMAE 《The Journal of reproduction and development》2014,60(2):106-114
Lactating Holstein-Friesian cows kept in tie-stall barn were used as subjects in this
study. Rectal examination, ultrasonography and blood sampling were conducted every other
day and then daily after the day on which diameter of the corpus luteum decreased. After
the luteal diameter decreased for 2 consecutive days, rectal and ultrasound examinations,
blood sampling, and observation of estrous signs were conducted at 6-h intervals. Most of
the estrous signs became obvious with the increase in estradiol-17β (E2) and
became most remarkable 24 to 30 hours before ovulation, at which point the E2
peak and luteinizing hormone (LH) surge were achieved, and then weakened which progression
to ovulation. The correlation between the intensity of four estrous signs (hyperemia and
swelling of the intravaginal part of the uterus, opening of the external uterine orifice
and viscosity of the cervical mucus) and the plasma E2 concentration was higher
than that of three estrous signs (swelling of the vulva, contraction of the uterus,
diameter of uterine horn) and the plasma E2 concentration. The relaxation of
the intravaginal part of the uterus showed a unique change compared with the other estrous
signs, and it became most obvious 6, 12 and 18 h before ovulation; this obviously relaxed
period was consistent with the generally accepted theoretical optimal time for artificial
insemination (AI), i.e., 6 to 24 h after initiation of estrus. These results suggest that
observation of estrous signs by vaginoscopic examination gave useful information for
detection of the optimal timing of AI in the periovulatory period in lactating dairy cows
kept in a tie-stall barn. 相似文献