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991.
为了解安徽、福建、广东、湖南、江苏、上海等6省市活禽批发商户和零售商户对"1110"制度的认知和态度,及其主要活禽销售行为,并探讨其相关性,以便有针对性地实施宣传干预,降低H7N9发病风险,采用自行设计的调查问卷,结合现场调查,对199户活禽销售商户进行了调查。结果显示:活禽销售商户的"1110"制度知晓率、接受率普遍偏低,其中批发商户和零售商户的知晓率分别为32.61%(30/92)和40.19%(43/107),接受率分别为20.65%(19/92)和28.04%(30/107),均无统计学差异(P0.05);多种活禽销售行为存在统计学差异(P0.05);零售商户的认知与态度呈正相关(P0.05);认知和态度与部分销售行为相关(P0.05)。因此,应对活禽销售商户加强"1110"制度宣传,促使其形成积极正向的态度,转变不良销售行为,从而提高活禽市场生物安全水平。 相似文献
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LIANG Zijing ZHANG Jingyan ZHANG Kai WANG Lei WANG Xurong ZHANG Kang LI Jianxi 《中国畜牧兽医》2018,45(3):830-840
In order to know more about the overview of the global polysaccharide characterization research,we analyzed the outputs of polysaccharide characterization research articles based on Web of ScienceTM database from 2008 to 2017.According to all the database of Web of ScienceTM,"polysaccharide characterization" or "polysaccharide structure" as the title words of this paper were used to analyze the current situation and the trend of the research on polysaccharide characterization by bibliometrics methods,in terms of the output of papers,the countries/regions,scientific research institutions,journals,authors,citations and research direction.The results showed that the output of papers have been arised in the world.China was the leading country in the field of polysaccharide characterization.The published papers of the Russian Academy of Sciences toped the list.Chinese Academy of Sciences toped the list in domestic institutions.The authors who published the most amount of papers were from Russian Academy of Sciences.The journal of Britain’s "Carbohydrate Polymers" had the largest number of papers.The most cited paper was from University of Georgia.The direction of the research was mainly concentrated in biochemistry and molecular biology,chemistry and agriculture,and it embodied the highly interdisciplinary nature.There were homology on polysaccharide characterization analysis methods in different countries,compared with China,the United States,Russia and Britain are more cutting edge on the application of polysaccharide. 相似文献
995.
试验根据中兽医治疗奶牛乳房炎的辨证施治原则,筛选出抑制引起奶牛乳房炎主要病原菌(金黄色葡萄球菌和大肠杆菌)的最佳中药组方,为其临床防治提供新的途径与方法。选用蒲公英、马齿苋、金银花、紫花地丁、赤芍、白芍、菊花、黄芩、漏芦、红花10味中药,通过L12(211)正交试验初步筛选抗菌中药组方中的最佳优选因素,再通过L16(45)正交试验进一步筛选药物组方配比;采用牛津杯法测定中药组方对奶牛乳房炎主要致病菌的体外抑菌效果;采用二倍稀释法和平板计数法分别测定中药组方对奶牛乳房炎主要致病菌最小抑菌浓度(MIC)和最小杀菌浓度(MBC)。结果显示,通过L12(211)正交试验初步筛选出了抗菌中药组方最佳优选因素:赤芍、黄芩、红花、菊花和白芍;L16(45)正交试验进一步筛选药物组方最佳配比为黄芩:赤芍:菊花:白芍:红花=3:3:3:1:2;新药组方对大肠杆菌的抑菌直径为17.39 mm,MIC和MBC分别为62.50、125.00 mg/mL,对金黄色葡萄球菌的抑菌直径为25.44 mm,MIC和MBC均为31.25 mg/mL。本研究成功筛选出了一种对奶牛乳房炎主要致病菌具有良好抑菌、杀菌作用的中药新配比组方。 相似文献
996.
以奥尼罗非鱼为饲养对象研究低鱼粉饲料对罗非鱼生长性能的影响。将500尾个体大小相似(35.12±0.80 g)的罗非鱼随机放入25个已消毒的圆形水族箱(高1 m、直径80 cm)中,平均每箱20尾。将25箱罗非鱼分为5组,每组5个重复,分别标号记录,按照要求给各组饲喂对照组饲料和4种不同的低鱼粉饲料,并在试验期间测定各组罗非鱼的体重、体长、全长和体高等数据。结果表明,各试验组罗非鱼的增重情况、体长增长量、全长增长量及体高增长量等与对照组罗非鱼之间无显著差异(P0.05)。利用低鱼粉饲料饲养罗非鱼是可行的。 相似文献
997.
Optimum Dietary Protein Level and Protein‐to‐energy Ratio for Growth of Juvenile Parrot Fish,Oplegnathus fasciatus 下载免费PDF全文
Kang‐Woong Kim Kyoung‐Duck Kim Hyon Sob Han Mohammad Moniruzzaman Hyeonho Yun Seunghan Lee Sungchul C. Bai 《Journal of the World Aquaculture Society》2017,48(3):467-477
An 8‐wk feeding trial was conducted to estimate the optimum dietary protein level and protein‐to‐energy (P/E) ratio in juvenile parrot fish, Oplegnathus fasciatus. Eight experimental diets were formulated with two energy levels and four protein levels for each energy level. Diets containing crude protein (CP) at 35, 40, 45, and 50% had either 12.5 or 14.6 kJ/g of energy. Fish averaging 7.1 ± 0.06 g (mean ± SD) were fed one of the experimental diets for 8 wk. At the end of the feeding trial, weight gain (WG) of fish fed 45 and 50% CP in the 12.5 kJ/g diet was significantly higher than fish fed the 35% CP diet (P < 0.05). WG of the fish fed 45 and 50% CP in the 14.6 kJ/g diet was significantly higher than fish fed the 35 and 40% CP diets (P < 0.05). Fish fed the 14.6 kJ/g diet had a higher WG compared with fish fed the 12.5 kJ/g diet at all CP levels. Feed efficiency (FE) and specific growth rate (SGR) showed a similar trend to the WG. WG, FE, and SGR improved with increasing dietary protein levels up to 45% and remained constant at 50% CP for both energy levels. However, protein efficiency ratio was negatively related to dietary protein levels. The results suggested that the optimum level of protein and the optimum P/E ratio for juvenile parrot fish should be 45% and 31.1 mg protein/kJ, respectively, in a diet containing 14.6 kJ/g energy. 相似文献
998.
为探讨云南蓝果树(Nyssa yunnanensis W.C.Yin)的濒危机理,运用解析木的原理,结合1979—2009年的气象数据,对两株云南蓝果树风倒木进行研究,分析主要气候因子对云南蓝果树生长指标的影响。结果表明:云南蓝果树的径向、高度和年轮宽度的年增长量呈逐渐下降趋势,而材积年生长量呈上升趋势。云南蓝果树生境自1979—2009年年平均气温缓慢地升高,年总降水量和年平均相对湿度值呈总体减少趋势;年均径向、高度生长量和年轮宽度与年平均气温呈负相关,与年降水量和相对湿度呈正相关;年均材积生长量与年均气温呈正相关,与年降水量和相对湿度呈负相关。 相似文献
999.
Du Xing-bin ;CHEN Chen ;LUO Li-jun ;XIA Long-ping ;LIU Kang ;CHEN Yin-hua ;Yu Xin-qiao 《水稻科学》2014,21(4):210-216
To study the effects of long-term no-tillage direct seeding mode on rice yield and the soil physiochemical property in a rice-rapeseed rotation system,a comparative experiment with a water-saving and drought-resistance rice(WDR)variety and a double low rapeseed variety as materials was conducted under no-tillage direct seeding(NTDS)mode and conventional tillage direct seeding(CTDS)mode for four years,using the CTDS mode as the control.Compared with the CTDS mode,the actual rice yield of WDR decreased by 8.10%at the first year,whereas the plant height,spikelet number per panicle,spikelet fertility,1000-grain weight,grain yield,actual yield,and harvest index increased with no-tillage years,which led to the actual yield increase by 6.49%at the fourth year.Correlation analysis showed that the panicle length was significantly related to the actual yield of WDR.Compared with the CTDS mode in terms of the soil properties,the pH value of the NTDS mode decreased every year,whereas the contents of soil organic matter and total N of the NTDS mode increased.In the 0–5 cm layer of the NTDS mode,the soil bulk decreased,whereas the contents of soil organic matter,total N,and available N increased.In the 5–20 cm layer of the NTDS mode,the available N and K decreased,whereas the soil bulk,contents of soil organic matter,and total N increased.In summary,the NTDS mode increased the rice yield,and could improve the paddy soil fertility of the top layer. 相似文献
1000.