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1.
试验对水牛发情周期血清和唾液中雌二醇(E_2)和孕酮(P_4)的浓度变化规律、水牛唾液结晶与卵泡发育变化分别进行了分析研究,为进一步探讨水牛发情规律、指导生产提供依据。采用酶联免疫分析法(ELISA)测定发情母水牛血清和唾液中E_2和P_4的浓度变化,并对血清和唾液的激素变化规律进行相关性分析。结果表明,水牛血清和唾液中的E_2和P_4呈波动性变化。发情前期,唾液中P_4浓度一直维持在6.50～7.10 ng/mL,发情第13天达到11.09 ng/mL,随后快速下降。唾液中E_2浓度在发情第3～5天出现一个峰值178.53 pg/mL,在第14～17天唾液中E_2浓度显著升高,出现第二个峰值179.10 pg/mL。母水牛唾液中E_2和P_4浓度的变化趋势与其在血清中的变化趋势基本一致,均呈显著相关(P<0.05);唾液中E_2与P_4浓度呈极显著相关(P<0.01)。水牛发情当天唾液结晶呈现明显的蕨类作物形状且分维值显著低于其他时间点(P<0.05)。水牛发情周期唾液结晶图形的变化与卵巢卵泡发育基本同步,可作为监测水牛发情及预测排卵的可靠指标之一。 相似文献
2.
试验对水牛发情周期血清和唾液中雌二醇(E_2)和孕酮(P_4)的浓度变化规律、水牛唾液结晶与卵泡发育变化分别进行了分析研究,为进一步探讨水牛发情规律、指导生产提供依据。采用酶联免疫分析法(ELISA)测定发情母水牛血清和唾液中E_2和P_4的浓度变化,并对血清和唾液的激素变化规律进行相关性分析。结果表明,水牛血清和唾液中的E_2和P_4呈波动性变化。发情前期,唾液中P_4浓度一直维持在6.50～7.10 ng/mL,发情第13天达到11.09 ng/mL,随后快速下降。唾液中E_2浓度在发情第3～5天出现一个峰值178.53 pg/mL,在第14～17天唾液中E_2浓度显著升高,出现第二个峰值179.10 pg/mL。母水牛唾液中E_2和P_4浓度的变化趋势与其在血清中的变化趋势基本一致,均呈显著相关(P0.05);唾液中E_2与P_4浓度呈极显著相关(P0.01)。水牛发情当天唾液结晶呈现明显的蕨类作物形状且分维值显著低于其他时间点(P0.05)。水牛发情周期唾液结晶图形的变化与卵巢卵泡发育基本同步,可作为监测水牛发情及预测排卵的可靠指标之一。 相似文献
3.
试验旨在探究围产期亚临床酮病与泌乳早期奶牛繁殖性能、卵泡发育之间的关系,并检测试验牛血液生化指标的变化。试验在黑龙江某大型集约化牛场开展,根据产后血酮水平确定亚临床酮病组（SCK）和健康组（C）奶牛共60头,根据试验牛产后50 d内发情状况,将SCK组再分为发情组（SCKE,16头）和乏情组（SCKA,14头）,C组也同样分为发情组（CE,25头）和乏情组（CA,5头）。所有试验牛在产后50 d通过直肠检查和B超检查了解子宫复旧及卵泡发育状况,记录繁殖性能数据,并进行血液生化指标分析。结果表明：与健康组发情奶牛相比,亚临床酮病发情奶牛产后首次发情日期推迟约10 d（P<0.05）;产后50 d卵泡直径差异极显著（差值约4 mm）（P<0.01）。亚临床酮病乏情奶牛子宫复旧延迟发生率显著高于健康组发情奶牛（P<0.05）;亚临床酮病奶牛血浆中胰岛素样生长因子-1（IGF-1）含量显著低于健康奶牛（P<0.05）,而泌乳量极显著提高（P<0.01）。与发情奶牛相比,乏情奶牛血浆中甘油三酯（TG）含量显著升高（P<0.05）;葡萄糖（Glu）、胰岛素（Ins）、雌二醇（E2）、孕酮（P4）含量显著或极显著降低（P<0.05;P<0.01）。综合以上试验结果,奶牛患亚临床酮病而导致能量代谢指标异常是引起奶牛乏情、产后卵泡发育受阻和繁殖障碍的主要因素,进而导致奶牛繁殖力下降。 相似文献
4.
为研究中草药集中催情和孕马血清促性腺激素（PMSG）外源诱导对非繁殖季节内蒙古绒山羊产羔和血清指标的影响,选取体重相近的内蒙古绒山羊272只,分为中草药试验Ⅰ组（112只）、激素试验Ⅱ组（100只）和对照组（60只）,试验Ⅰ组饲喂中草药,每次50 g/只,发情前7 d开始饲喂,每2 d饲喂1次,共3次;试验Ⅱ组海绵栓+PMSG 250 IU/只;对照组正常饲养。在试验结束后第2天早饲前各组选择5只羊颈静脉采血,测定并分析血清中生理生化指标及生殖激素含量的变化。结果显示,试验Ⅰ组和试验Ⅱ组绒山羊的发情率、产羔率和双羔率极显著高于对照组（P<0.01）,试验Ⅱ组的产羔率和双羔率极显著高于试验Ⅰ组（P<0.01）,发情率显著高于试验Ⅰ组（P<0.05）。试验Ⅱ组绒山羊血清总蛋白（TP）、白蛋白（ALB）、尿素氮（UREA）、谷胱甘肽过氧化物酶（GSH-Px）含量显著高于试验Ⅰ组和对照组（P<0.05）,试验Ⅰ组绒山羊丙二醛（MDA）含量、超氧化物歧化酶（SOD）活性显著高于试验Ⅱ组和对照组（P<0.05）;试验Ⅱ组血清促卵泡素（FSH）、雌二醇（E2）和促黄体素（LH）含量显著高于对照组（P<0.05）,孕酮（P4）、睾酮（T）在三组之间差异均不显著（P>0.05）,试验Ⅰ组生殖激素指标与对照组差异均不显著（P>0.05）。对激素和抗氧化酶的相关性分析显示,试验Ⅰ组绒山羊血清P4含量与GSH-Px含量呈显著负相关（P<0.05）,其相关系数为-0.594,试验Ⅱ组绒山羊血清LH含量与GSH-Px含量呈极显著正相关（P<0.01）,其相关系数为0.757。本研究结果表明,中草药和激素处理均可极显著促进内蒙古绒山羊在非繁殖季节集中发情,并提高产羔率。激素处理可提高非繁殖季节内蒙古绒山羊对蛋白质的消化利用程度和抗氧化功能,中草药处理可提高血清SOD活性;分析认为GSH-Px与P4之间存在显著颉颃作用,GSH-Px与LH之间存在极显著协同作用。 相似文献
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[目的]对广西水牛发情周期唾液和血液中雌激素(E2)和孕酮(P4)的浓度变化规律及相关性进行了分析,为进一步探讨水牛发情规律来指导生产提供依据。[方法]采用酶联免疫分析方法(ELISA)测定发情母水牛血液和唾液中E2(雌二醇)和P4(孕酮)的浓度变化,并对血液和唾液的激素变化规律进行了相关性分析。[结果]广西水牛血液和唾液中的E2和P4呈波动性变化,结果表明,发情前期,唾液中P4浓度一直维持在6.57.1ng/mL,第13天达到11.09ng/mL以上,随后快速下降。唾液中E2浓度在发情前期第35天出现一个峰值178.528pg/mL,在1417d唾液中E2浓度显著升高,出现第二个峰值达到120.57pg/mL。唾液E2和P4浓度的变化趋势和血清E2和P4浓度的变化趋势基本一致,相关性较好。母水牛唾液和血清样品的P4浓度相关性显著(R=0.4080;P0.05),母水牛唾液和血清标本的E2浓度相关性显著(R=0.5113;P0.05)母水牛唾液E2和P4浓度相关性非常显著(R=0.7754;P0.01)。[结论]唾液和血液中的这两种激素水平起伏变化基本趋于一致,其相关性显著,可以作为监测水牛发情及预测排卵的可靠指标之一。 相似文献
7.
本试验旨在探究生长分化因子9（GDF9）对卵丘细胞扩展相关基因和激素受体基因表达量及激素分泌的影响,为GDF9在绵羊卵泡发育中的作用提供依据。以绵羊卵丘细胞为研究对象,通过在低血清细胞培养液中添加不同浓度（0、50、100、200、400 ng/mL）的GDF9,培养绵羊卵丘细胞48 h后,提取细胞总RNA,利用实时荧光定量PCR技术,以β-actin为内参基因,检测卵丘细胞扩展相关基因透明质酸合酶2（HAS2）、前列腺素内过氧化物合酶2（PTGS2）、穿透素3（PTX3）及激素受体相关基因卵泡刺激素受体（FSHR）、促黄体生成素受体（LHR）和雌激素受体（E2R）的mRNA相对表达量;利用酶联免疫吸附法（ELISA）测定培养液中卵丘细胞分泌的雌二醇（E2）和孕酮（P4）含量。结果显示：在细胞培养液中添加200 ng/mL GDF9时,HAS2、PTX3、FSHR、E2R和LHR的mRNA相对表达量极显著高于对照组与其他处理组（P<0.01）;PTGS2 mRNA相对表达量极显著高于对照组、50和400 ng/mL GDF9组（P<0.01）,显著高于100 ng/mL GDF9组（P<0.05）。当添加400 ng/mL GDF9时,各基因mRNA相对表达量均极显著低于200 ng/mL GDF9组（P<0.01）;E2分泌量极显著高于对照组与50 ng/mL GDF9组（P<0.01）,显著高于100 ng/mL GDF9组,与200 ng/mL GDF9组差异不显著（P>0.05）。100、200和400 ng/mL GDF9组P4分泌量显著高于对照组（P<0.05）,与50 ng/mL GDF9组没有显著差异（P>0.05）,且3组之间差异不显著（P>0.05）。综上所述,GDF9能够促进绵羊卵丘细胞扩展,并参与绵羊卵丘细胞激素分泌的调控。 相似文献
8.
本研究旨在探讨饲喂N-氨甲酰谷氨酸（NCG）对奶牛超数排卵效果及血液生化指标的影响。选取荷斯坦育成牛16头，随机分为2组，每组8头，对照组饲喂基础饲粮，试验组在基础饲粮的基础上饲喂20 g/（d·头）的NCG，采用连续4 d递减注射FSH法测定NCG饲喂时间对供体牛超排效果的影响，分别在3次超排处理的第0、5、9天采集尾根静脉血测定激素指标及血清生化指标。结果表明，①NCG饲喂20 d时（第1次超排），试验组头均回收胚数、可用胚数、退化胚数、未受精卵数与对照组相比差异均不显著（P>0.05）；NCG饲喂50 d时（第2次超排），试验组头均回收胚数显著高于对照组（P<0.05）；NCG饲喂80 d时（第3次超排），试验组头均可用胚数显著高于对照组（P<0.05）；综合考虑3次超排效果，试验组头均回收胚数显著高于对照组（P<0.05）。②NCG饲喂时间对供体牛血清中促卵泡素、促黄体素、孕酮、雌二醇的浓度均无显著影响（P>0.05），说明NCG饲喂时间对奶牛生殖激素的分泌无影响或为次要影响因素，超排效果的变化与生殖激素变化无明显的关联作用。③NCG饲喂时间对供体牛血清中谷草转氨酶的浓度无显著影响（P>0.05）；在NCG饲喂13 d时，试验组供体牛血清中葡萄糖浓度显著高于对照组（P<0.05）；在NCG饲喂34 d时，试验组供体牛血清中尿素氮浓度显著低于对照组（P<0.05）；在NCG饲喂43和69 d时，试验组供体牛血清中一氧化氮浓度显著高于对照组（P<0.05）。综合考虑，在重复3次超排时，每头供体牛每天饲喂20 g NCG，可提高3次连续超排的回收胚数4.98枚及可用胚数1.8枚，进而降低胚胎的生产成本。 相似文献
9.
沼泽型水牛发情期血清生殖激素的变化规律研究 总被引：1，自引：0，他引：1
研究应用RIA法对沼泽型水牛发情期的血清生殖激素浓度进行测定,并分析了生殖激素的变化规律。结果表明:①同期发情的水牛在处理后至发情当天均有2个E2峰出现,第1个在发情前,第2个在发情后并与LH峰同时或之前2 h;②PMSG(肌注)+PG(肌注)处理的水牛出现发情前E2峰、发情后FSH峰和LH峰的时间为处理后24、60 h和63 h,而PMSG(肌注)+PG(子宫灌注)+LH(肌注)处理的水牛出现发情前E2峰、发情后FSH峰和LH峰的时间为处理后48、80 h和82 h;③各组水牛P4水平在发情后48 h内均低于0.8 ng/mL;④与自然发情水牛对比,同期发情处理可显著影响其发情期的FSH和LH内源性分泌水平(P<0.05);而对E2和P4均没有产生显著性的变化(P>0.05)。 相似文献
10.
不同卵泡波类型水牛生殖激素变化的试验研究 总被引：1，自引：1，他引：0
为了了解不同卵泡波类型水牛的生殖激素变化情况与卵泡波之间的关系,试验对已探明卵泡波类型的6头沼泽型水牛采集经同期发情处理后的血样,采用放射免疫测定法(RIA)测定其血清生殖激素浓度,分析比较不同卵泡波类型水牛的生殖激素变化情况。结果发现3个卵泡波青年水牛的促卵泡素(FSH)水平在发情周期第15 d后明显高于表现为2个卵泡波的青年水牛(P<0.05);黄体素(LH)水平则相反,在第15 d前,2波周期的青年水牛其黄体素(LH)水平明显高于3波周期的青年水牛。3波周期的青年水牛,其E2、P4水平要高于2波周期的青年水牛。血清促卵泡素(FSH)、黄体素(LH)、雌二醇(E2)、孕酮(P4)水平在表现为不同卵泡波类型的水牛中并不存在显著差异(P>0.05)。 相似文献
11.
为研究排卵延迟奶牛发情配种后黄体的变化规律及其差异性,本研究在临床症状观察、直肠检查和B超辅助检查诊断的基础上,选取8头排卵延迟奶牛(排卵延迟组)、5头健康正常发情奶牛(对照组),应用B超对黄体的相关指标(直径、面积、周长和体积)进行了测量及分析,对获得的不同阶段典型黄体声像图进行了描述。结果显示,与对照组相比,排卵延迟组与对照组奶牛黄体的直径、面积、周长和体积在发情配种后7~15 d差异均不显著(P>0.05)。在发情配种后第9和13天排卵延迟组奶牛黄体相关指标(直径、体积、面积和周长)大于对照组奶牛,而在第11天小于对照组奶牛。结果表明,排卵延迟奶牛发情后不同阶段B超黄体直径、面积、周长和体积与正常发情排卵后的相应指标没有显著差别。 相似文献
12.
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
13.
Mejia-Guadarrama CA Pasquier A Dourmad JY Prunier A Quesnel H 《Journal of animal science》2002,80(12):3286-3300
Low protein intake during lactation has been demonstrated to increase the loss of body protein and to reduce the reproductive performance of female pigs. The objectives of the current experiment were 1) to determine whether protein (lysine) restriction alters levels of somatotropic hormones, insulin, follicle-stimulating hormone, and leptin around weaning, and 2) to evaluate the relationships between these eventual alterations and postweaning reproductive performance. One day after farrowing, crossbred primiparous sows were randomly allocated to one of two diets containing 20% crude protein and 1.08% lysine (C, n = 12) or 10% crude protein and 0.50% lysine (L, n = 14) during a 28-d lactation. Diets provided similar amounts of metabolizable energy (3.1 Mcal/kg). Feed allowance was restricted to 4.2 kg/d throughout lactation, and litter size was standardized to 10 per sow within 5 d after farrowing. Catheters were fitted in the jugular vein of 21 sows around d 22 of lactation. Serial blood samples were collected 1 d before (day W - 1) and 1 d after (day W + 1) weaning, and single blood samples were collected daily from weaning until d 6 postweaning (day W + 6). Sows were monitored for estrus and inseminated. They were slaughtered at d 30 of gestation. During lactation, litter weight gain was similar among treatment groups. Reduced protein intake increased (P < 0.001) sow weight loss (-30 vs -19 kg) and estimated protein mobilization throughout lactation (-4.1 vs -2.0 kg). On day W - 1, L sows had higher (P < 0.02) plasma glutamine and alanine concentrations, but lower (P < 0.05) plasma tryptophan and urea than C sows. Mean and basal plasma GH were higher (P < 0.001), whereas plasma IGF-I and mean insulin were lower in L than in C sows on day W - 1. Preprandial leptin did not differ between treatments on day W - 1, but was higher (P < 0.01) in L sows than in C sows on day W + 1. Mean FSH concentrations were similar in both treatments on day W - 1 (1.3 ng/mL), but L sows had greater (P < 0.001) mean FSH on day W + 1 than C sows (1.6 vs 1.2 ng/mL). The weaning-to-estrus interval (5 +/- 1 d) was similar in both groups. Ovulation rate was lower in L than in C sows (20.0 +/- 1 vs 23.4 +/- 1, P < 0.05). No obvious relationships between reproductive traits and metabolic hormone data were observed. In conclusion, these results provide evidence that protein (lysine) restriction throughout lactation alters circulating concentrations of somatotropic hormones and insulin at the end of lactation and has a negative impact on postweaning ovulation rate. 相似文献
14.
Seventy-one 10th-generation gilts from White Line-1 (WL-1 = randomly selected control line) and White Line-2 (WL-2 = selected for an index of ovulation rate and prenatal survival rate) were used to compare the pattern of follicular development and atresia during the follicular phase of the estrous cycle. Gilts were treated with PGF(2alpha)on d 13 of the estrous cycle (d 0 of induced follicular development) to induce luteolysis and assigned randomly within line and sire for ovary recovery on d 0, 2, 3, 4, 5, and the day after estrus. Ovaries were evaluated for numbers of corpora albicantia and small (2 to 2.9 mm), medium (M1 = 3 to 4.9 mm; M2 = 5 to 6.9 mm), and large (>or=7 mm) follicles. The concentration of estradiol-17beta in follicular fluid was used to classify individual M2 and large follicles as estrogen-active (>or=100 ng of estradiol-17beta/mL) or inactive (<100 ng of estradiol-17beta/mL). The WL-2 gilts had a greater ovulation rate than WL-1 gilts at their pre-treatment estrus (20.4 vs. 13.8 corpora albicantia; P < 0.001). The small and M1 follicle populations decreased rapidly in both lines over time (P < 0.001). The M2 follicle population increased in both lines between d 0 to 4 and then decreased. Mean estradiol concentration of M2 follicles increased in both genetic lines over time (P < 0.02). All large follicles were estrogen-active in both lines; the number of large follicles increased with day (P < 0.001) and was similar in both lines. The number of estrogen-active M2 follicles was similar in both lines, increasing to d 3 and 4 and then decreasing (P < 0.01) thereafter. However, the total number of estrogen-active follicles (sum of estrogen-active M2 and large follicles) was greater in WL-2 than in WL-1 gilts (P < 0.04), increasing to the ovulatory potential by d 3 in WL-1 gilts, but continuing to increase through d 4 in WL-2 gilts. Selection of an additional six ovulatory follicles from the estrogen-active M2 follicle pool after d 5 was required in both lines to achieve the projected ovulation rate, and after estrus, the number of large follicles remained insufficient to attain the ovulatory potential of each line. 相似文献
15.
为掌握母牦牛繁殖季节促卵泡素(FSH)、促黄体激素(LH)、孕酮(P4)、瘦蛋白(Leptin)、雌二醇(17β-E2)激素含量变化,在牦牛繁殖季节对其卵巢、卵泡变化进行直肠检查,对FSH、LH、P4、Leptin、17β-E2激素进行测定。结果表明,牦牛在繁殖季节非发情期其FSH、LH、P4、Leptin、17β-E2含量在0.0836～0.3767(mIU/ml)、0.1350～1.0109(ng/ml)、3.1283～7.4809(pg/ml)、0.0650～8.0119(ng/ml)、0.1604～0.5139(mIU/ml)。在繁殖季节发情期以上激素含量分别为0.1280～0.4050(mIU/ml)、0.6820～1.6744(ng/ml)、3.1586～3.8438(pg/ml)、0.5275～1.3760(ng/ml)、0.4110～0.5975(mIU/ml)。由此说明牦牛繁殖季节非发情期和发情期其激素变化个体差异很大,因此牦牛发情期的长短个体差异较大。 相似文献
16.
Effects of postweaning dietary energy source on reproductive traits in primiparous sows 总被引：2，自引：0，他引：2
An experiment was conducted to study the effects of major dietary energy source fed from weaning to ovulation or from ovulation to d 35 of pregnancy on reproductive traits in primiparous sows. Dietary energy sources were used to manipulate the plasma insulin concentration. One hundred thirteen sows were used in a split-plot design. From weaning to ovulation sows were fed at two times maintenance either a diet with tallow (Fat) or maize starch plus dextrose (Starch) as the major energy source. From ovulation onward, sows within each dietary group were alternately reassigned to either the Fat or the Starch diet and were fed at 1.25 times maintenance. Estrus detection was performed three times a day from d 3 to 9 after weaning and sows were inseminated each day of standing estrus. On d 35 of pregnancy, the sows were slaughtered and their reproductive tracts were removed. Plasma insulin concentration was higher in sows fed the Starch-rich diet than in sows fed the Fat-rich diet on d 4 after weaning (1.30 vs 0.97 ng/mL, P = 0.08) and on d 32 of pregnancy (1.20 vs 0.51 ng/mL, P < 0.001). Plasma glucose and IGF-I concentration on d 4 after weaning and d 32 of pregnancy did not differ between sows on the two dietary energy sources. The percentage of sows exhibiting estrus within 9 d after weaning was 52 and 67% for the Fat and Starch diet before ovulation, respectively (P = 0.11), whereas the weaning-to-estrus interval was 134 vs 123 h, respectively (P = 0.12). Survival analysis showed that sows fed the Fat-rich diet had a 1.6 times higher risk to remain anestrous until d 9 after weaning than sows fed the Starch-rich diet (P = 0.04). No effect of dietary energy source, either before or after ovulation, on uterine, placental, or embryonal development on d 35 of pregnancy was found. It can be concluded that the dietary energy source provided after weaning can affect the risk of sows to remain anestrous but does not affect uterine, placental, or embryonic traits. 相似文献
17.
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
18.
Tatsuyuki YOSHIDA Makoto SEKI Norio WATANABE Hiroki FURUTA Itaru YOSHIMURA Masahiro OSADA Koji CHIBA Konosuke OKADA Koh KAWASUMI Hitoshi USHIJIMA 《Animal Science Journal》2012,83(3):207-212
Diagnosis of corpus luteum (CL) function by rectal palpation (RP) has been widely used for recipient selection of embryo transfer (ET), a technology essential for genetic improvements in cattle. To examine the accuracy of RP diagnosis method, the relationship between RP‐based CL function and reproductive performance was compared in this study. In Experiment 1, CL of Holstein heifers on day 7 after estrus was classified into functional or hypoplastic by RP, and the results were compared with ultrasonographic (US) images and plasma progesterone (P4) levels. As a result, heifers with functional CL judged by RP had a mean maximum CL diameter of 20.1 ± 3.1 mm on US and a mean P4 concentration of 8.1 ± 2.3 ng/mL. These values were significantly greater than those of heifers with hypoplastic CL (12.4 ± 5.4 mm, 4.0 ± 2.8 ng/mL) (P < 0.001). In Experiment 2, the length of the estrus cycle was examined between functional CL and hypoplastic CL. The rate of heifers with a normal estrus cycle length with 18–25 days was significantly lower with hypoplastic CL than with functional CL (16/24 vs. 43/46, P < 0.01). In Experiment 3, 543 inseminated heifers were similarly classified by CL function by RP 7 days after estrus. The heifers with functional CL showed higher pregnancy rate compared with the heifers with hypoplastic CL (75.2 vs. 47.9%, P < 0.0001). Finally, the CL function of 66 heifers was examined by RP on day 7 post‐estrus, and ET was performed in 49 (74.2%) heifers with functional CL. As a result, 27 (55.1%) of them became pregnant. Taken together, these results reconfirm that RP on day 7 after estrus is useful for selection of heifers with functional CL. 相似文献