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941.
942.
Shengtao FAN Tiecheng WANG Xiaolong GAO Ying YING Xue LI Yongcheng LI Yuanguo LI Jinzhu MA Heting SUN Dong CHU Yu XU Songtao YANG Qihan LI Yuwei GAO Xianzhu XIA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1143-1149
Newcastle disease virus (NDV) causes a highly contagious viral disease in poultry and
wild birds, and it can cause significant economic loss worldwide. Eight viral strains were
isolated by inoculating embryonated chicken eggs from the Poyang Lake region of China with
swab samples. All eight of the NDV isolates were identified as class I genotype 3 strains,
but they diverged notablely from class II viruses. Further analysis revealed that all
eight NDV isolates were lentogenic strains containing the
112ERQER↓L117 motif at the F protein cleavage site. The strains
were highly identical and were more species specific (chicken and waterfowl) than site
specific (Nanchang and Duchang regions). The close phylogenetic proximity of these
isolates indicates that viral transmission may happen between poultry and wild birds. Our
study demonstrates that lentogenic class I NDVs exist in clinically healthy wild waterfowl
and poultry within the Poyang Lake region. Active surveillance of these viruses to
determine their evolution and origin is one of the most realistic strategies for
preventing and controlling NDV outbreaks. 相似文献
943.
目的:比较不同浸提时间菌草鹿角灵芝超微粉和普通粉中多糖和三萜类溶出率的差异。方法:采用苯酚-硫酸法检测多糖含量,以齐墩果酸为标准品,采用紫外-可见分光光度法检测三萜类含量。结果:相同提取时间下,超微粉多糖和三萜类的溶出量分别比细粉的溶出量提高24%和15.2%,溶出度参数T50和Td检测结果显示,超微粉多糖、三萜类溶出速度也比细粉快,在90 min时超微粉多糖累计溶出量达到95%以上,三萜类在90%以上,而细粉的两项溶出量均仅为约70%。结论:超微粉碎技术有利于菌草鹿角灵芝有效成分的溶出。 相似文献
944.
黄土丘陵区白羊草与达乌里胡枝子混播草地土壤呼吸日变化特征 总被引:1,自引:0,他引:1
土壤呼吸是反映土壤质量和肥力性状的重要指标,阐明禾―豆混播草地土壤呼吸作用的变化规律及其影响因素,可以为准确评估混播草地的环境效应及响应提供依据。在2011和2012年6月份,采用动态密闭气室分析法,比较了白羊草(Bothriochloa ischaemum)与达乌里胡枝子(Lespedeza davurica)不同比例间作混播草地总土壤呼吸速率的日变化特征、混播植物贡献率以及温度敏感性等。结果表明,不同混播比例草地的总土壤呼吸速率日变化为单峰型曲线,峰值出现在12:00~14:00。总土壤呼吸速率日均值高低顺序为单播白羊草白羊草和达乌里胡枝子间作单播达乌里胡枝子。不同间作比例草地的总土壤呼吸速率与白昼气温相关显著(P0.05),而与5、10和15 cm土层白昼土壤温度关系不明显;单播条件下,白羊草草丛的土壤呼吸对温度的敏感性高于达乌里胡枝子;各草地土壤呼吸Q10值的变化范围为1.48~2.61,以单播白羊草最高,单播达乌里胡枝子和两者间作混播草地间无显著差异(P0.05)。 相似文献
945.
HOU Ning LV Zhi-hui ZHAO Liang GAO Xue-li LIU Chao-nan LV Xiao-ping ZHENG Shi-min 《中国畜牧兽医》2015,42(8):2183-2188
The 90 chickens were randomly divided into control group, E.necatrix one time infection group and E.necatrix two times infection group.We used duplex PCR method to test the expression changes of HSP-90 mRNA in intestinal tissue of chickens infected with E.necatrix and researched the effects of it comprehensively and systematically.The results were showed that after 0 to 14 days the expression of HSP-90 mRNA in intestinal tissues of 14-day-old chickens infected with E.necatrix presented a upward trend though it was lower than the control chickens.These chickens were infected with E.necatrix again at 28 days, HSP-90 mRNA expressions of duodenum, jejunum and ileum decreased and then increased.However, it always showed a downward trend in appendix.When 28 days chickens were infected with high-does E.necatrix once, HSP-90 mRNA expressions of duodenum, jejunum and appendix were in a declining curve.While it was increased originally and then decreased in ileum.This study indicated that HSP-90 mRNA expressions in intestinal tissue of chickens infected with E.necatrix were inhibited at first, and the expression quantity was closely related to the degrees of intestinal tissue damage. 相似文献
946.
LU Xin-xing YANG Jin-li WANG Hai-rong WANG Gui-chao GAO Ai-wu ZHANG Li-min HOU Xian-zhi 《中国畜牧兽医》2015,42(12):3202-3209
To study the effect of nutrient restriction and compensation on weight,serum indexes and gene expression of chest fat adipokine in Mongolian lamb,thirty male lambs were randomly divided into control group (20.26 kg± 3.63 kg) and feed restricted group (21.29 kg±3.00 kg).The experiment lasted for 120 days,including 60 days for feed restriction and 60 days for compensatory feed.At the end of each stage,five lambs from each group were slaughtered and chest fat was collected.Serum concentration of triglycerides,non-esterified fatty acids (NEFA),total cholesterol were measured.Quantitative Real-time PCR were used to determine Adiponectin,Visfatin,PPAR-γ and ACC genes expression.The results showed that:①The lamb body weight of restricted group kept maintain level and that of control group showed a increase tendency.During the compensatory period,the average daily gain (ADG) of restricted group was significantly higher than control group (P< 0.05).②During the restriction period,serum triglycerides concentration of lambs in restricted group was significantly decreased at day 30 and 60 (P< 0.05),and NEFA concentration was significantly increased at day 30 (P< 0.05).After 60 days of nutritional compensation,all serum parameters we tested were not significantly different between restrict group and control group (P >0.05).③During the restriction period,PPAR-γ and ACC gene expression in restricted group were significantly lower than that of control group (P< 0.05),while no significant differences were found during the compensation period (P>0.05).Adiponectin and Visfatin genes expression in chest fat was not significantly changed throughout the experiment (P >0.05).We could know that nutritional restriction reduced fatty acid synthesis and adipocyte differentiation ability,adipose tissue was mobilized energy metabolism,and total cholesterol was recoveried growth on the compensation.However,the ACC and PPAR-γ genes in restricted group were significantly decreased with the body weight increased rapidly during the compensatory stage.Adiponectin and Visfatin were not significantly different between restricted and compensatory stages. 相似文献
947.
948.
以引自甘肃省小陇山林业科学研究所的15个丽江云杉家系3年生苗为材料,于国有樟村坪林场造林,观测各家系的成活率、保存率、树高、当年新梢长、地径、南北平均冠幅和一级分枝数,并对家系间6个生长性状指标进行分析。结果表明:7年生时,15个丽江云杉家系间保存率和新稍长的差异均不显著,树高和冠幅的差异均达极显著,地径和一级分枝数的差异均达显著。综合选择出的3个优良家系7年生平均树高比其它12个家系的平均树高提高16.5%,当年新稍长提高10.9%,地径提高4.6%,冠幅提高10.9%,保存率提高3.4%。 相似文献
949.
杉木根、枝和叶的C、N、P生态化学计量特征 总被引:1,自引:0,他引:1
以湖南会同杉木基地Ⅲ号集水区25年生杉木人工林为研究对象,测定1月份杉木根、枝和叶的C、N、P含量,研究其C、N、P生态化学计量特征。结果表明:杉木根、枝和叶中C含量平均值分别为561.04、515.93、513.56 g/kg,表现为根枝叶;N含量平均值分别为6.86、8.78、7.97 g/kg,表现为枝叶根;P含量平均值分别为1.45、0.71、1.54 g/kg,表现为叶根枝。根的C∶N、C∶P、N∶P的平均值分别为92.50、521.72、5.29;枝的C∶N、C∶P、N∶P的平均值分别为65.17、789.82、12.46;叶的C∶N、C∶P、N∶P的平均值分别为69.31、355.56、5.53。叶的C含量和枝的呈显著正相关;叶的N含量和枝的呈极显著正相关;叶的N含量和根的呈极显著正相关;P的含量在根、枝和叶之间均呈显著正相关。 相似文献
950.