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1.
奶牛子宫内膜炎是引起奶牛不孕的常见疾病之一。我县一规模奶牛场共存栏奶牛约980头,其中成年适繁母牛460头,均为全年舍饲饲养。2010年该场奶牛子宫内膜炎发病率高达55%以上,严重影响了本场的生产和发展。该实验从我县一规模奶牛场中共收集病例100头,分成4组,每组25头,经过2个疗程的治疗和对比试验,结果表明使用宫净康进行子宫内灌注治疗奶牛子宫内膜炎效果非常好。 相似文献
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Jawahar Lal Katara Ram Lakhan Verma Debkanta Nayak Umakanta Ngangkham Soham Ray Hatanath Subudhi Lambodar Behera Sanghamitra Samantaray Ravi Nageswara Rao Onkar Nath Singh Trilochan Mohapatra 《Plant Breeding》2017,136(1):74-82
Identification of new parental lines is crucial for developing ecology‐specific hybrids with ideal agronomic performance. We screened a total of 570 different ecology‐specific Indian rice varieties for the presence of fertility restorer genes, Rf3 and Rf4 using tightly linked markers DRRM Rf3‐10 and RM6100, respectively. Among these varieties, 13% carried Rf3Rf3/Rf4Rf4, 31% carried rf3rf3/rf4rf4, 6% carried Rf3Rf3/rf4rf4 and remaining 50% carried Rf4Rf4/rf3rf3 allelic combinations. A mini set of 40 varieties with variable allelic combinations of fertility restorer genes were testcrossed with WA and Kalinga‐based CMS lines. All the 80 F1s were evaluated for spikelet fertility and fertility restoration ability. Rf3Rf3/rf4rf4 genotypes mostly behaved as partial maintainers or partial restorers. In contrast, rf3rf3/Rf4Rf4 genotypes were partial or effective restorers. However, double dominant genotypes showed better fertility restoration than the genotypes containing Rf3 or Rf4 individually. Some of the genotypes showed unexpected restoration pattern implying occurrence of other fertility restorer(s) apart from Rf3 and Rf4. The perfect restorers and maintainers identified in this study can be directly used in hybrid rice breeding. 相似文献
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Objective Guinea pigs have a very low threshold of corneal sensitivity and at the same time nearly no reflex tearing compared to dogs, cats, and horses. The question arose whether there is a general correlation between corneal sensitivity and the quantity of reflex tearing. Animals studied Totally 160 animals of 8 different species (20 animals per species) were investigated. Procedures The corneal touch threshold (CTT) was measured with a Cochet–Bonnet esthesiometer. The palpebral fissure length (PFL) was measured with a calliper ruler. The Schirmer tear test (STT) was modified by adapting the width of the STT strip to the PFL of every species. For the STT II, 0.4% oxybuprocaine was applied. Results Corneal touch threshold: Cows (1.67 g/mm2), horses (1.23 g/mm2), sheep (1.13 g/mm2), goats (1.44 g/mm2), dogs (2.16 g/mm2), and cats (1.33 g/mm2) show similar CTT values. In contrast, rabbits (6.21 g/mm2) and guinea pigs (7.75 g/mm2) show a significantly lower CTT. Tear Production Difference STT I ? STT II: Rabbits have the greatest decline in tear production with 38.4%, followed by sheep (33.3%), dogs (31.1%), cats (24.7%), cows (23.7%), horses (18.0%), and goats (14.0%). Guinea pigs have no decline, but a slight increase of ?16.0%. Correlation CTT and STT II ? STT I Difference: Pearson’s correlation coefficient shows a small, but significant correlation. The coefficient of determination can only forecast a value with 7.1% certainty. Conclusions The high variance and low reproducibility of results suggest that the measuring devices are inappropriate to assess the evaluated parameters. Therefore, no assured correlation between the corneal sensitivity and the quantity of reflex tearing could be found. 相似文献
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为满足企业对液压缸产品测试的可靠性与自动化需求,对液压缸综合性能测试台的测控系统进行了研究与设计,满足企业需求,提高生产效率,保证生产质量。通过伺服液压缸对被测试缸加载,结合被测缸自身测试功能,通过PLC可编程控制技术对油路中各个阀体的控制,测试液压缸产品的各项性能,提高检测精度试验台的设计,以及巧妙的工装设计,提高测试台的通用性。实验台机械结构紧凑,布局合理,一目了然,便于操作,便于检查维修,模块化设计的实验系统具有良好的开放性和可拓展性。 相似文献
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李新平 《中国农村水利水电》2011,(5)
基于一榀单跨两层矩形钢管混凝土框架的抗震性能试验,利用通用有限元软件ABAQUS建立了框架的非线性有限元分析模型,模型中考虑了混凝土反复荷栽下的刚度退化.通过与试验结果的对比分析,验证了该模型的正确性,可以用于矩形钢管混凝土框架的结构分析中.利用该模型对不同轴压比下框架的骨架曲线进行了对比,并对其受力性能进行了分析,结果表明:随着轴压比的增大,框架的延性和承载力随之降低. 相似文献
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李凯捷 《林业机械与木工设备》2009,37(11):40-41
GB19725—2005《便携式割灌机和割草机安全要求》中,附录C抛物试验是GB/T14176—2003《便携式割灌机和割草机技术条件》3.6安全要求中重要的检测项目。根据抛射物体的形状和抛射物体试验的要求,开发设计了抛射物体试验台,以完善割灌机安全性能试验项目的检测。 相似文献
10.
For reproductive success, flowering time must synchronize with favourable environmental conditions. Vernalization genes play a major role in accelerating or delaying the time to flowering. We studied how different vernalization (VRN1) gene combinations alter days to flowering and maturity and consequently the effect on grain yield and other agronomic traits. The study focussed on the effect of the VRN1 gene series (Vrn‐A1, Vrn‐B1 and Vrn‐D1) and their combinations. The Vrn gene group Vrn‐A1a, Vrn‐B1, vrn‐D1 was the earliest to flower and mature, while Vrn‐A1b, Vrn‐B1, vrn‐D1 was the latest to flower. Spring wheat lines with vrn‐A1, Vrn‐B1, Vrn‐D1 were the highest yielding and matured at a similar time as those having vernalization genes Vrn‐A1a, Vrn‐B1 and Vrn‐D1. The findings of this study suggest that the presence of Vrn‐D1 has a direct or indirect role in producing higher grain yield. We therefore suggest the introduction of Vrn‐D1 allele into higher‐yielding classes within Canadian spring wheat germplasm. 相似文献