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1.
乳汁雌二醇(E2)与孕酮(P4)含量是判断母牛卵巢机能状态的重要指标。本试验建立了E2与P4奶样纸片酶免法,P4检测灵敏度达到2.1 pg,回收率91%,板内和板间变异系数分别为5.3%(n=8)和10.4%(n=10);E2检测灵敏度达到1.7 pg,回收率89%,板内和板间变异系数分别为4.8%(n=7)和9.6%(n=10)。将该方法用于测定定时排卵程序中母牛乳汁E2与P4含量,结果表明所建立的方法简便实用,排卵程序中母牛乳汁E2、P4变化规律与理论分析相符,可以用来判定母牛发情、妊娠及卵巢功能。 相似文献
2.
超数排卵母牛血浆孕酮、雌二醇和促黄体素含量与卵巢反应及胚胎质量的关系 总被引：2，自引：0，他引：2
对9头FSH超排母牛血浆孕酮,雌二醇和促黄体素水平进行了研究。超排第1天到发情后第4天的血浆孕酮含量与排卵数的相关不显著,发情后第7天的孕酮含量与排卵数的相关极显著(r=0.849.P<0.01);发情前的雌二醇含量与排卵数有弱的正相关,发情后第7天的雌二醇含量与排卵数有极显著的负相关(r=-0.809,P<0.01);促黄体素的含量与排卵数无关。另将供体母牛随机分为A、B两组,A组注射LRH—A_3,B组不注射,作对照。结果发现,两组间排卵数、采卵数,可用卵数和未排大卵泡数的差异在统计上均不显著。本试验结果表明,超排前血浆孕酮含量不适宜预测卵巢反应,而发情后第7天的孕酮含量是评定卵巢反应的一项合适的指标。超排时给予LRH-A_3的效果虽不十分显著,但有正效果,值得进一步研究。 相似文献
3.
孕酮主要是由卵巢的黄体细胞及妊娠期的胎盘组织所分泌的。在母牛生殖的不同阶段,血浆孕酮的变化富有特征性(图1)。许多学者发现乳汁孕酮的变化与血浆孕酮的含量同步(图2),根据乳汁的孕酮量可以描绘出母牛生殖过程所发生的生理变化,包括黄体的形成及其分泌活动的连续或结束等。因此,根据乳汁孕酮的变化可检查 相似文献
4.
《中国牛业科学》1990,(4)
利用201头乏情肉用母牛研究埋植雌二醇对诱发产后卵巢周期的影响。选自4个农场有2个泌乳期以上的母牛,用雌二醇和产后时期作为主要处理,以2×3因子排列进行试验。在同一农场内依产犊资料随机抽取母牛,耳根埋植17β—雌二醇21天, 不埋植的作为对照。在埋植时,把产后时期划分为。产后≤25,26—39和≥40天,这3个阶段反映了下丘脑—垂体对雌二醇敏感性的潜在变化。在埋植嵌入时,埋植后14天,取去埋植(21)、取去埋植后14天(35天)分别采血样测定孕酮和对卵巢进行直肠检查,以估测处理对排卵反应。在处理14天时,对照和雌二醇处理母牛的血中,雌二醇浓度平均分别为3.2±1.0和23.1±4.7pg/ml。在试期内,在产后26天用雌二醇处理的和对照组母牛比较,可提高排卵母牛的比例。母牛第一个检测有排卵的产后平均天数似乎没有差异。 相似文献
5.
当前人工授精技术在全国已广泛应用，人工授精受胎率也随着技术水平的提高而逐年提高。由于人工授精受胎率直接与母牛的排卵及配种时间有关，而且影响非常大，所以试用药物调整和控制母牛发情和排卵时间，在生产上有着非常重要的意义。Maplatoft利用PRID（孕激素阴道栓）、P4-EB（孕酮＋苯甲酸雌二醇）、PGF2α（前列腺烯醇）和EB（苯甲酸雌二醇）来调控青年母牛发情、排卵及定时进行人工授精，取得了良好效果。据此，我们设计了此试验。本试验采用对40头母牛不经发情鉴定的方法。而通过PRID、P4-EB、PGF2α和EB处理后，直接进行人工授精的方法，获得了较高的妊娠率。 相似文献
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8.
《中国兽医杂志》2016,(2)
为了解孕酮免疫生物传感器的临床应用效果,本试验对7头妊娠奶牛,8头产后发情奶牛和18头乏情奶牛的血浆雌二醇、促黄体素、促卵泡素和孕酮浓度进行了检测,同时应用的孕酮免疫生物传感器进行了乳汁孕酮检测。结果显示,孕酮免疫生物传感器检测的乳汁孕酮水平与ELISA检测血浆孕酮含量之间呈正相关。该优化的生物传感器检测奶牛妊娠的孕酮浓度范围为10~15 ng/mL,发情的孕酮浓度范围为4~10 ng/mL;持久黄体的孕酮浓度范围为10~16 ng/mL,卵巢静止的孕酮浓度范围为3~7 ng/mL,黄体囊肿的孕酮浓度范围为12~18 ng/mL。表明该孕酮免疫生物传感器能有效的检测奶牛妊娠、发情和繁殖障碍疾病的乳汁孕酮水平。 相似文献
9.
应用放射免疫法对10头黑白花母牛性周期内乳汁孕酮含量进行了测定。结果显示母牛配种当天(0天)乳汁不含孕酮,配种后第3天含量仍是低值(范围0—4ng/ml,平均0.71±1.338)。以后逐渐上升,配种后第13天,70%个体出现峰值(范围14.8～36.5ng/ml,平均24.9±6.73);其余个体于配种后第16天出现峰值(范围15—31ng/ml,平均24.83±8.6)。此后显示分化现象,其波动曲线与同类报道相似。 相似文献
10.
本实验采用放射免疫测定技术(RIA)分析了9头屡配不孕母牛和6头正常母牛于发情开始后8天内的血清雌二酵和孕酮含量的变化。测定结果表明:屡配不孕母牛发情开始时的血清雌二醇水平低于正常母牛(7.4±3.4pg/ml VS 14.2±6.3pg/ml p<0.025)。发情开后96小时内屡配不孕母牛的血清孕酮水平的变化范围为0.90～1.76ng/ml,正常母牛的变化范围为0.68～1.00ng/ml。发情开始后192小时,正常母牛的血清孕酮水平已经达到2.47±2.02ng/ml,而屡配不孕母牛的血清孕酮水平则为1.97±0.60ng/ml。实验结果指示:体内内分泌失调可能是导致母牛屡配不孕的重要原因之一。 相似文献
11.
Petersson KJ Strandberg E Gustafsson H Royal MD Berglund B 《Preventive veterinary medicine》2008,86(1-2):153-163
We examined whether infrequent milk sampling for progesterone analysis could be used as a management or diagnostic tool by the dairy farmer to predict delayed ovarian cyclicity in dairy cows. The data included 1040 lactations from 324 Swedish Red cows and 183 Swedish Holstein cows and were randomly divided into two datasets. A logistic regression model was fit to the first dataset and the model was then validated on the other dataset. The model was also validated using a British dataset comprising 1212 lactations from 1080 British Holstein-Friesian cows. The dependent variable was whether delayed ovarian cyclicity occurred or not, delayed ovarian cyclicity defined as progesterone levels below threshold value for the first 56 or 45 days postpartum in the Swedish or British dataset, respectively. The basic model included the effects of breed, parity, season and housing type. To the basic model various progesterone-based measurements were added. These were the interval from calving to commencement of luteal activity and the percentage of samples with luteal activity within 60 days after calving, using all samples in the databases or one sample per month. The accuracy of the conditional probability of delayed ovarian cyclicity calculated with the different models was obtained using receiver operating characteristic (ROC) curves and calculating the area under curve. Sensitivity and specificity were calculated for cut-off probabilities using the ROC analyses. The accuracy was highest (0.94-0.99) when including the progesterone measurements based on milk sampling for progesterone analysis 2-3 times per week. The accuracy was between 0.85 and 0.88 when the progesterone measurements with monthly milk sampling were added to the model and 0.76 or 0.67 with the basic model. This study clearly shows that infrequent milk sampling for progesterone analysis, such as once a month as in the regular milk recording system, could be used to predict delayed ovarian cyclicity in dairy cows. This increases the opportunity for earlier treatment of anovulatory dairy cows and may therefore decrease involuntarily extended calving intervals in the herd. 相似文献
12.
The present study was undertaken to show the incidence of silent ovulation in high producing dairy cows, by monitoring ovarian cyclicity based on practical milk progesterone assay which was established in this study. The direct milk progesterone enzyme linked immunosorbent assay (ELISA) was developed using anti-progesterone-3(E)-carboxymethyloxime-BSA antibody for the antibody and horse radish peroxidase labeled progesterone for tracer. High sensitivity (26 pg/mL, 0.65 pg/well), high recovery rates (83-97%), high reproducibility (CV of intra-assay 4.8-11.5%; CV of inter-assay 14.3-19.1%) and high correlation between milk progesterone concentrations measured by the direct ELISA and the values obtained by the ELISA after extraction proved the reliability of the assay. In second experiment the incidence of silent ovulation was investigated based on the milk progesterone concentrations in 32 dairy cows within 70 days post partum. The incidences of silent ovulation at the first, second, third and fourth ovulation post partum were 83, 46, 13 and 0%, respectively. Most commonly observed patterns of sequential occurrence of silent ovulation in cows ovulating 2, 3 or 4 times within 70 days post partum were silent-estrus (50%), silent-silent-estrus (60%) and silent-silent-estrus-estrus (67%), respectively. These results suggest that the present ELISA is a reliable and practically applicable method for determination of progesterone in milk and that high producing dairy cows show a high incidence of silent ovulation at the first post partum ovulation as well as the second ovulation, which then decreased with the increased frequency of ovulation. 相似文献
13.
Concentrations of oestradiol-17 beta and progesterone in defatted milk have been used to study the post-partum restoration of ovarian function in 52 autumn-calved dairy cattle. In 32 cows the first preovulatory peaks in oestradiol-17 beta concentration (indicative of imminent ovulation) were less than or equal to 15 days and in 49 cows less than or equal to 49 days post partum. Delay to first ovulation was mainly due, not to failure of ovarian secretion of oestradiol-17 beta at preovulatory level, but to failure of oestradiol-17 beta at this level to exert its normal preovulatory function. Longer intervals to first ovulation were associated with longer intervals from calving to the clearance of placental oestradiol-17 beta, high peak milk yields and high body weight losses, suggesting that in high-yielding dairy cows these factors (themselves inter-related) may be associated with others, which are the immediate cause of the inhibition of the normal, preovulatory function of oestradiol-17 beta. Forty-eight per cent of cows had short, first ovulation cycles. Ovarian function, comprising oestradiol-17 beta secretion at preovulatory level, normal preovulatory function of oestradiol-17 beta and normal corpus luteum progesterone secretion were almost fully restored in this herd by the 49th day post partum. 相似文献
14.
【目的】本研究基于试验测定的中国荷斯坦牛血液和乳汁中的孕酮浓度表型，探究了影响中国荷斯坦牛体内孕酮分泌的环境因素、孕酮浓度的变化趋势、孕酮浓度与乳成分的关联程度以及血乳中孕酮浓度的预测方法。【方法】试验于2021年8月在北京、山东两个牧场采集不同胎次、泌乳阶段和妊娠状态的中国荷斯坦泌乳牛的奶样、尾根血样，测定孕酮浓度，最终获得402条乳汁孕酮浓度和298条血液孕酮浓度表型用于数据分析。对孕酮浓度进行数据转化使其近似服从正态分布后，采用固定效应模型探究胎次、泌乳阶段、妊娠状态、牧场等固定效应对奶牛孕酮表型的影响，运用R语言cor函数计算孕酮与各乳成分间的关联，并利用偏最小二乘法和个体及乳成分信息对孕酮浓度进行预测，以建立孕酮浓度表型高通量获取手段。【结果】妊娠状态对转化乳汁孕酮浓度存在极显著影响（P<0.01），胎次、场效应对转化乳汁孕酮浓度均有显著影响（P<0.05），而转化血液孕酮浓度只受到妊娠状态影响（P<0.01）；全乳固体、乳脂率、乳蛋白率、脂蛋比与转化乳血孕酮浓度均存在显著或极显著的正相关关系（r=0.14~0.37，P<0.05；P<0.01）；基于本试验数据，乳成分与个体信息对转化乳血孕酮浓度的预测准确性不高（R2=0.030~0.17），但如果增加血液或乳汁的转化孕酮浓度对乳汁或血液的转化孕酮浓度进行预测，预测效果则有大幅提升（R2=0.40）。【结论】影响泌乳期中国荷斯坦牛转化孕酮浓度的因素除妊娠状态外，可能还包括饲养条件与胎次。此外转化孕酮浓度与乳脂率、乳蛋白率等乳成分呈极显著相关。基于乳成分信息与转化孕酮的关系，获得了对中国荷斯坦牛乳血转化孕酮浓度预测的可用策略，为今后牧场的繁殖辅助管理、奶牛育种新性状研发以及孕酮浓度的高通量获取等提供了新思路。 相似文献
15.
J Eldon 《Acta veterinaria Scandinavica》1991,32(3):377-386
The progesterone level of milk was measured daily in 20 Icelandic dairy cows for 50-90 days post-partum and for 30-50 days post-conception by radioimmunoassay. In 40% of the cows the 1st post-partum ovarian cycle was shorter and the progesterone level lower than in normal cycles. The average duration of the 1st post-partum luteal phase was significantly shorter and the progesterone values lower than in the 2nd and 3rd phases. The progesterone level rose to a plateau at the onset of luteal function within 5 +/- 2 (mean +/- s.d.) days, whereas the decrease in progesterone at the end of the luteal phase was more rapid i.e. 3 +/- 1 days. The progesterone value for a normal interluteal phase was 1.5 +/- 1.3 nmol/l. However in 9 of 48 interluteal phases the progesterone values did not decline below 3 nmol/l. The average progesterone concentration was significantly increased during the first 30 days post-conception. In 4 of 20 cows a significant drop in progesterone concentration was found 15-19 days post-conception. The results indicate that the luteal activity of the 1st post-partum ovarian cycle is inferior to that of the following cycles. There is a significant correlation in the intensity of the luteal activity between cycles. Ovarian cyclicity continues in early pregnancy in, at least, 20% of cows. The sampling frequency is of importance in studies concerning the luteal activity. 相似文献
16.
The incidence of low day 5 milk progesterone in dairy cows has been investigated and the efficacy of treating the problem assessed. The incidence of inadequate milk progesterone (empirically defined as <3ng/mL) in repeat breeder cows was 34% compared with 11.4% in first insemination cows. Treatment with an intravaginal progesterone device for 7 days starting from day 5 or 6 did not improve pregnancy rate. Treatment with 1500 iu human chorionic gonadotrophin (hCG) on day 5 gave an increase in pregnancy rate that was dependent on initial progesterone concentration and significant (P<0.05) in multiparous but not primiparous cows. While the incidence of inadequate day 5 progesterone was high in repeat breeder cows, it was responsive to hCG treatment, although only in multiparous and not primiparous animals. 相似文献
17.
Use of milk progesterone enzyme immunoassay for differential diagnosis of follicular cyst, luteal cyst, and cystic corpus luteum in cows 总被引：1，自引：0，他引：1
T Nakao A Sugihashi N Saga N Tsunoda K Kawata 《American journal of veterinary research》1983,44(5):888-890
In 160 cows with ovarian cysts as determined by rectal palpation, differentiation was made of follicular cyst, luteal cyst, and cystic corpus luteum on the basis of milk progesterone concentrations estimated by an enzyme immunoassay before and at 10 days after cows were treated with gonadotropin-releasing hormone. Cows having a progesterone concentration in skim milk less than 1.0 ng/ml were considered to have follicular cysts and those with concentrations of 1.0 ng/ml or higher were regarded as the cases of luteal cyst or cystic corpus luteum. Luteal cyst was characterized by progesterone values remaining high in the cows for 10 days after treatment, and cystic corpus luteum was characterized by a decrease in progesterone concentration after cows were treated. By the rectal palpation procedure it was impossible to differentiate luteal cyst and cystic corpus luteum from follicular cyst. The frequencies of follicular cyst, luteal cyst, and cystic corpus luteum were 65%, 19%, and 16%, respectively. Of 104 cows with follicular cysts as defined by milk progesterone assay result, 73 (70%) responded to the treatment with gonadotropin-releasing hormone, the milk progesterone concentration increasing from 0.7 +/- 0.2 ng/ml (mean +/- SD) to 1.8 +/- 1.1 ng/ml. The accuracy of rectal palpation 10 days after treatment for judgment of luteinization of follicular cyst confirmed by milk progesterone analysis was only 30% (48 cows of 160). 相似文献
18.
A field study on the usefulness of milk progesterone determination to confirm estrus and pregnancy of dairy cows in the Fraser Valley area of British Columbia 
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下载免费PDF全文 Rajamahendran R Burton B Shelford J 《The Canadian veterinary journal. La revue veterinaire canadienne》1993,34(6):349-352
A field study was conducted to determine the usefulness of milk progesterone determination at the time of breeding to confirm estrus and at 21 days postbreeding to detect open cows. Twenty-seven dairy farmers collaborated in this study by providing milk samples on the day of breeding and 21 days later, together with pregnancy diagnosis data and information on herd reproductive management. Herd size ranged from 15 to 175 cows, the average being 65 milking cows. Six hundred and sixty-seven breeding-day samples and 472, 21-day samples were provided by the farmers. Analysis of milk samples for progesterone by a solid phase radioimmunoassay showed that only 32 (4.8%) of the services were performed when the cow was not in estrus (progesterone > 1 ng/mL). Of the 472, 21-day samples, 337 (71%) showed progesterone levels of > 1 ng/mL, while 135 (29%) showed progesterone levels of < 1 ng/mL. Subsequently, 243 (72%) of the cows with progesterone > 1 ng/mL and eight (6%) of the cows with progesterone < 1 ng/mL were diagnosed pregnant by transrectal palpation, giving a pregnancy rate of 53%. Progesterone concentration on the day of breeding was not associated with season or herd size. However, progesterone concentration at 21 days and pregnancy rate were associated with herd size. These results indicate that fertillzation failure and/or early embryonic mortality, rather than inaccurate detection of estrus, are the major reproductive problems encountered by the dairy farmers in British Columbia. Furthermore, progesterone values at 21 days were closely related to reproductive status and indicate the usefulness of milk progesterone assay for the early detection of open cows. 相似文献
19.
Our objectives were to investigate the effects of genotype, yield and composition of milk, and changes in BW and body condition on the initiation of cyclic ovarian activity in nonsuckled beef and dairy cows milked twice daily. Nulliparous heifers were selected from three breeds, 12 Angus, 13 Simmentals, and 26 Holsteins, based on their EBV for milk yield. Cows were machine-milked twice daily, and daily milk yield was recorded; composite samples of milk were collected twice weekly for analyses of milk components. Blood was collected from all cows thrice weekly for 75 d postpartum, and concentrations of progesterone in serum measured by RIA were used to estimate day of first postpartum ovulation. Holstein cows produced more (P less than .05) milk (unadjusted or 3.5% fat-corrected) than Angus or Simmental cows during the first 30 d of lactation. Holstein cows had higher (P less than .01) peak yield of milk than Simmental and Angus cows. Days to peak milk yield were similar for Simmental and Holstein cows, and both were more (P less than .05) than those for Angus cows. Percentages of fat, protein, and total solids in milk were highest (P less than .05) for Simmental cows, whereas milk of Holstein cows had the highest (P less than .05) percentage of lactose and lowest (P less than .05) concentration of somatic cells. Average BW at ovulation differed (P less than .05) among breeds. Estimated daily changes in BW from calving to first ovulation were different (P less than .05) for Holstein and Simmental cows but were similar to those of Angus cows.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献