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AEM Horta JP Barbas CC Marques MC Baptista MI Vasques RM Pereira RD Mascarenhas S Cavaco‐Gonçalves 《Reproduction in domestic animals》2010,45(6):e412-e416
The effect of vaginal administration of misoprostol plus terbutaline sulphate 6 h prior to artificial insemination (AI) upon the site of AI (vaginal or cervical) and fertility was studied using a total of 87 estrous synchronized Serra da Estrela ewes (control n = 42 and treated n = 45). Artificial insemination was performed using refrigerated semen at 54–55 h after sponge removal. Lambing rate (fertility) and prolificacy were compared between control and treated ewes. The effect of the site of semen deposition on fertility was also evaluated. Prolificacy rate was not different between control (1.5) and treated (1.59) ewes. The proportion of cervical AI achieved in control (45.2%) and treated (37.8%) ewes was not significantly different. Overall, fertility was significantly lower in control than in treated ewes (42.9% vs 64.4%; p < 0.04). Fertility following vaginal AI was significantly lower for control for than treated ewes (30.4% vs 60.7%; p < 0.03) but the difference was smaller and not significant for cervical AI (control 57.9% vs 70.6%). It was concluded that vaginal administration of misoprostol plus terbutaline sulphate 6 h prior to artificial insemination did not affect the proportion of cervical inseminations but significantly improved the fertility of treated ewes. Although needing confirmation, it was hypothesized that drugs might have induced local secretory modifications leading to an increase of cervical ability to retain more viable spermatozoa for fertilization. 相似文献
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在U形壳槽横向内力计算中,若不考虑槽底局部加厚对Φ=90°截面内力的影响,则计算所得的该截面弯矩绝对值偏小.温度变化对截面内力的影响较大,特别是温降引起多数截面的弯矩增加,而轴向力减少;温升引起Φ=90°截面弯矩与轴向拉力均增加,再考虑槽底局部加厚的影响,弯矩值还要增加.槽底局部加厚与温度变化的作用均不能忽略不计,否则,内力计算成果值会偏于不安全.用结构力学方法,推导出二者对内力影响的计算公式,并附有应用的算例. 相似文献
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Encapsulated Stuphylococcus aureus from bovine mastitis 总被引：1，自引：0，他引：1
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Nineteen does (female goats) were dosed with 500,000 oocytes of Hammondia hammondi prior to breeding. At about 90 days of gestation these, and 18 uninoculated does were challenged with 25,000 Toxoplasma gondii oocysts. The 19 H. hammondi--inoculated does produced 26 live and one dead kid (newborn goat). The 18 does not given H. hammondi produced 12 live and 19 dead kids. However, examination of all of the kids by isolation of T. gondii in mice, serology and histology revealed that they were all infected with T. gondii. Thus, while H. hammondi "vaccination" is protective against the deleterious effects of T. gondii on pregnant does, perhaps by reducing the severity of placental lesions, it does not prevent foetal infection. 相似文献
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为了解沧州市滨海盐碱区耕层土壤的盐渍化特征,采集三个时期沧州不同地区耕层土壤（0~20 cm）样品,结合样品实验分析,探究土壤盐分特征。结果表明：①沧州滨海盐碱区耕层土壤离子类型多样,检测的八大离子中氯离子、钠离子、硫酸根、碳酸根+碳酸氢根离子为主要盐分离子,土壤类型为硫酸盐-氯化物型。②相关分析表明,耕层土样中总含盐量与氯离子和钠离子均存在显著或极显著相关关系,沧州市滨海盐碱地耕层土壤的总含盐量一定程上取决于土壤中氯化钠的含量;氯化钠、氯化镁和氯化钙为氯化物的主要组成部分;主要硫酸盐类为硫酸钠、硫酸镁和硫酸钙。③方差分析表明,三个不同采样时期和不同地区均对沧州市滨海区盐碱地的盐渍化的影响存在显著或极显著差异。④主成分分析表明,钠离子、氯离子、镁离子、钙离子和硫酸根与第1主成分相关性较高;钾离子和碳酸根+碳酸氢根与第2主成分相关性较高;第3主成分主要反映硅酸盐类对土壤离子成分的影响。由于钠离子、氯离子、钙离子和硫酸根在土壤中含量相对较高,是表征沧州滨海盐碱区土壤盐渍化的主要特征因子。 相似文献