郑州动物园鹤球虫感染调查

为了解鹤球虫的感染种类和流行情况,对郑州市动物园5个品种的圈养成年鹤采集34份粪便样品进行检查.结果表明,球虫总感染率为35.29%,平均感染强度(OPG)为2.08×104.发现有3种球虫寄生于鹤,分别为鹤艾美尔球虫(Eimeria gruis)、瑞氏艾美尔球虫(Eimeria reichenowi)和拉氏等孢球虫(Isospora lacazei).     

贵州小香乌鸡血浆同工酶的遗传多态性

为揭示贵州小香乌鸡血浆同工酶遗传特点，采用连续的聚丙烯酰胺凝胶水平式电泳(PAGE)技术分析了80份贵州小香乌鸡血浆中的淀粉酶(Amy-1、Amy-2)、碱性磷酸酶(Akp-1、Akp-2)、酯酶-1(Es-1)同工酶的遗传多态性，发现除Akp-2座位呈单态外，其余4个座位均有多态性，多态座位百分比和平均杂合度分别为P=0.8000、H=0.2778。对有关座位基因频率进行计算发现小香乌鸡akp-1、Akp-2°、Amy-2     

华北落叶松人工幼林林分密度与生物量的关系

华北落叶松（larix principis—rupprechtii Mayr．）是燕山山地的主要树种，生态和经济效益显著。以河北木兰林管局境内13a生华北落叶松人工幼林为研究对象，用样方调查的方法对立地条件相同密度分别为1800、2400和3000株／hm^2的3种林分生物量进行研究，结果表明：林分总生物量随密度的增大而增大，低、中、高3种密度林分总生物量分别为21180．6、26724．6和31352．4kg/hm^2；乔木层生物量最大，占总生物量的98．9％，草本层次之，占0．7％，灌木层最少，仅占0．4％；林木平均木生物量随密度的增大略微减少，密度由低到高其平均木生物量依次为11537．5、11077．3和10357．8g/株；各密度林分乔木层各器官生物量均存在W干〉W枝〉W根〉W叶〉W皮的分布规律；3种密度的林分生物量结构特征基本相同，3000株／hm^2的林分结构合理，更能达到丰产的目的。     

贵州部分地方鸡品种血浆淀粉酶的多态性

采用水平板聚丙烯酰胺凝胶电泳法,对贵州、河南、广东、江西部分地方鸡品种及有关外来鸡种共１３个种群１２２５只个体的血分酶的多态性进行了检测。结果显示：在Ａｍｙ－１位点,出现Ａ和Ｂ两条活性带,形成ＡＡ、ＡＢ、ＢＢ３种表型类型。χ＾２检验表明,以ＡＢ型杂合子的频率显著为高,３种表型的分布极显著偏离了Ｈａｒｄｙ－Ｗｅｉｎｂｅｒｇ平衡比例。贵州小香乌骨鸡只有ＡＢ型,没有ＡＡ型和ＢＢ型。在Ａｍｙ－２位点发现在     

Host status of Brachypodium distachyon to the cereal cyst nematode

Cereal cyst nematode(Heterodera avenae, CCN) distributes worldwide and has caused severe damage to cereal crops, and a model host will greatly aid in the study of this nematode. In this research, we assessed the sensitivity of 25 inbred lines of Brachypodium distachyon to H. avenae from Beijing, China. All lines of B. distachyon were infested by secondstage juveniles(J2s) of H. avenae from Daxing District of Beijing population, but only 13 inbred lines reproduced 0.2–3 cysts/plant, showing resistance. The entire root system of the infested B. distachyon appeared smaller and the fibrous roots were shorter and less numerous. We found that a dose of 1 000 J2s of H. avenae was sufficient for nematode infestation. We showed that Koz-1 of B. distachyon could reproduce more cysts than TR2A line. Line Koz-1 also supported the complete life cycles of 5 CCN geographical populations belonging to the Ha1 or Ha3 pathotype group. Our results suggest that B. distachyon is a host for CCN.     

利用电穿孔法对狂犬病病毒SRV9 Ψ区缺失株病毒的拯救及鉴定

探讨电穿孔转染法对SRV9Ψ区缺失株重组病毒的拯救及鉴定。利用电穿孔细胞转染法,将纯化的Ψ区缺失株pcDNA-NPMG-L全长质粒和pcDNA-N、pcDNA-P、pcDNA-M、pcDNA-G和pcDNA-L辅助表达质粒共转染至BHK-21细胞中,并进行盲传,借助RT-PCR、间接免疫荧光试验、Western-blot及透射电子显微镜对重组病毒进行鉴定。结果显示,重组病毒能够产生绿色荧光,透射电子显微镜观察可见典型的弹状病毒,对重组毒株与亲本毒株G蛋白进行Western-blot验证,可获得相应目的条带。结果表明,通过电穿孔细胞转染法,能成功拯救出重组病毒SRV9Ψ区缺失株,为病毒的拯救提供新的转染方法,并能有效提高转染效率,为研发新型狂犬病疫苗提供参考。     

Effects of Energy Level on Growth Performance,Slaughter Performance,Ruminal Fermentation Parameters and Rumen Microorganisms Number in House-fed Yaks

This experiment was conducted to investigate the effects of energy level on growth performance,slaughter performance,ruminal fermentation parameters and the number of several rumen microorganisms in house-fed yaks. Single factor randomized block design was adopted in this study,and sixty healthy 3-year-old Maiwa yaks with an average body weight of (192.66±3.64) kg were randomly divided into 3 groups with 20 replicates per group and 1 yak per replicate. Diets for all groups had the same crude protein content (14.81%) and different net energy levels for gain (NE_g) with 4.17(LE),4.48(ME) and 4.79(HE) MJ/kg,respectively. The experiment was lasted for 97 days (7-day pretrial period and 90-day feeding trial). The results showed that compared with LE group,average daily gain (ADG) of ME (1 099.89 g/d) and HE (1 019.02 g/d) were increased by 27.26%(P < 0.01) and 17.90%(P < 0.01),respectively,the F/G trended to be significantly decreased (P=0.073) and slaughter rate trended to be significantly increased (P=0.092) than that of LE group. However,no significant difference was found on the dry matter intake (DMI) and net meat percentage among all treatment groups (P > 0.05).With the increase of diet energy level, pH in yak rumen tended to decrease significantly (P=0.064), and that of ME group was the lowest.The increase of diet energy level tended to significantly affect the isobutyric acid concentration (P=0.063) and the ratio of acetic acid to propionic acid (P=0.074).Total volatile fatty acids (TVFA) and acetic acid concentration of ME group were significantly higher than the other two groups (P < 0.05),of which the valeric acid concentration was extremely significantly increased with the increase of the diet energy level (P < 0.01).Increasing dietary energy level had a trend to decrease the relative content of R.flavefaciens,but there was no significant effects on the relative content of R.albus and F.succinogenes (P > 0.05). In conclusion,we recommend 4.48 MJ/kg (DM basis) as a diet appropriate NE_g level for the barn feeding of fattening yak under this experimental condition.     

节水改造前后永济灌域地下水环境时空变化特征

地下水是我国西北干旱半干旱区的重要资源,而大规模的节水改造工程势必造成地下水环境的变化。本文从时空概率分布角度,探索了河套灌区永济灌域节水改造前（1998—2000年）、初期（2001—2006年）、中期（2007—2012年）和后期（2013—2018年）地下水埋深和地下水矿化度的时空变化特征,并运用指示Kriging法分析了节水改造前后不同阈值条件下地下水埋深和矿化度的空间概率分布规律。结果表明：（1）随着节水改造工程的推进,地下水埋深和矿化度均呈增加趋势,节水改造后期（2013—2018年）较节水改造前（1998—2000年）平均埋深增加了0.36 m,矿化度增加了1.37 g·L^-1。（2）空间尺度上,节水改造后期33%的浅埋地下水（地下水埋深<2.0 m）高概率区（发生概率在0.5以上）过渡为深埋地下水的高概率区,且受城镇化影响（开采利用量大）,中南部和北部地下水埋深增加显著;矿化度<2.5 g·L^-1和≥3.0 g·L^-1的高概率区分别扩大了17%和4%,即研究区中南部地下水趋于淡化,北部及东西边...     

速冻汤圆的研究现状及发展趋势

汤圆是我国的一种传统糯米制品,深受消费者喜爱。针对速冻汤圆的原辅料选择、品质评价指标及贮藏条件的研究现状进行归纳,并结合对现有研究的了解与思考,提出了速冻汤圆在市场未来发展的方向。