陶赛特羊和小尾寒羊在青海湟源地区的生态适应性分析

为评定引入青海省湟源县良种肉羊繁育基地的陶赛特羊和小尾寒羊两个绵羊品种的生态适应性,对其18个生理生化指标进行了系统测定分析,结果表明：①引入的陶赛特羊和小尾寒羊两个绵羊品种大多数生理生化指标在品种内或不同品种间的不同性别、不同年龄个体间以及同性别、同年龄个体间差异不显著（P〉0.05）。②两绵羊品种所测血浆CO2结合力远超出本地藏绵羊水平;体温（T）、呼吸频率（R）、脉搏（P）和瘤胃蠕动频率以及白细胞数（WBC）、红细胞数（RBC）、血红蛋白含量（HGB）的测定结果均大致在本地藏绵羊的各生理指标测定范围之内。③与已引入青海牧区的小尾寒羊大多数生理生化指标相比,本次引进的小尾寒羊在经过一段时间的适应性饲养后,其大多数生理生化指标已与其基本接近或一致;同时,引入的陶赛特羊和小尾寒羊与原产地相应品种在基础生理指标上相比较接近。     

单宁对反刍动物的影响及其消除方法概述

单宁是一种多酚化合物,广泛存在于各种植物中。本文对其性质、营养作用、对反刍动物的不利影响以及消除方法作了综述。     

冬季常见鸡呼吸道病的防治

随着冬季的来临,养鸡生产过程中,经常遇到鸡呼吸道病,鸡只不仅生长发育受影响,而且因死亡及耗用药物造成经济上严重损失。引起鸡群出现呼吸道病症的原因很多,鸡舍的通风、温度及湿度之间的矛盾,使鸡在冬季长期处于缺氧、低温、高湿、高氨、高二氧化碳的恶劣环境之中,导致鸡抵抗能力降低、易患疾病,特别是呼吸道疾病。养鸡者在作出诊断和类似病症鉴别时往往感到困难。现就冬     

A riverscape perspective on habitat associations among riverine bird assemblages in the Lake Champlain Basin,USA

The riverscape perspective recognizes the heterogeneous habitat types within the stream corridor as a single, integrated ecological unit operating across spatial scales. Although there is ample evidence that the riverscape notion is appropriate in understanding the physical phenomena of stream corridors, significantly less attention has focused on its ecological ramifications. To this end, we surveyed riverscape habitat variables and bird community characteristics in the Champlain Valley of Vermont, USA. From the data collected, we used information theoretic methodology (AIC_c) to model relationships between bird community attributes and key habitat variables across the riverscape. Our models with the greatest support suggest that riverine bird communities respond to a suite of characteristics; representing a variety of riverscape habitats at the in-stream, floodplain, and riparian levels. Channel slope, drainage area, percent conifers, and in-stream habitat condition were among the most influential variables. We found that piscivores are potentially important indicators of riverscape condition, responding to a host of variables across the riverscape. Our results endorse a holistic approach to assessing and managing the mosaic of patches in the riverscape and suggest that a riverscape approach has significant conservation potential.     

Quantification of airborne spores of <Emphasis Type="Italic">Monilinia fructicola</Emphasis> in stone fruit orchards of California using real-time PCR

The fungal pathogen Monilinia fructicola causes blossom blight and fruit brown rot of stone fruits in California. In this study, spore densities in the air were monitored in six orchard/year combinations with Burkard spore traps. A real-time PCR assay was developed to efficiently quantify the dynamics of spore density in these orchards during the growing season. Different patterns of dynamics of spore density were observed in these orchards. A linear relationship between numbers of spores counted with a compound microscope and those determined with the real-time PCR assay was obtained, using the same samples of spore traps. Spore density in five of six orchard/year combinations ranged from 0.0 to 0.05 spores l⁻¹, except for that in orchard 4, which showed much higher values of spore density in the air, as well as higher values and wider range of incidences of blossom infection and fruit rot than those in the other orchards. The results demonstrated a potential method to quantitatively determine spore inoculum potential in orchards by using a real-time PCR assay.     

基因芯片在百合无症病毒检测中的应用

设计百合无症病毒、植物18SrRNA基因的特异扩增引物和各种对照的探针，将探针固定在醛基化玻璃片基上，完成植物基因芯片制备。提取百合种球总RNA，经RT-PCR扩增相应区段并用Cy3dCTP进行标记，用标记的PCR产物与芯片杂交，扫描仪对杂交结果进行扫描，GenePixProd．0软件对杂交图像进行分析。结果从荷兰进口的百合种球中检测出百合无症病毒，证明了该实验研制的植物病毒基因芯片的准确性和灵敏性。     

浅谈动物防疫监督中补检和隔离措施的运用

补检是指对未经检疫而进入经营流通环节的动物、动物产品所进行的检疫。具有适用范围广、操作方便、不受时间和空间限制等优点，是一项动物防疫监督中不可缺少的终结措施。动物防疫监督中如果对补检措施运用不当或滥用．会产生一些与动物防疫工作相悖的弊端．在一定程度上会影响正常的防检疫工作秩序。[第一段]     

使用Reveal试剂盒快速检测单增李斯特氏菌的研究

单核细胞增生李斯特氏菌(Listeria monocytogens,LM,简称为单增李斯特氏菌)是食品卫生上重要的病原菌。它广泛存在于自然界,可导致人和动物脑膜炎、流产、败血症等,病死率高达30%-70%,是目前人类最重要的食物源性病原菌之一。由于该菌生长温度范围较广,在     

水稻白叶枯病菌毒素对水稻不育系珍汕97A的专化毒性

 采用乙酸乙酯法提取对珍汕97不育胞质具有专化毒性的白叶枯病菌AH28、GX50和非专化毒性的OS14菌株的毒素。以不同浓度的毒素处理珍汕97不育系和保持系的种子或幼苗,可引起水稻叶片褪绿和细胞坏死,产生与接种病菌相似的症状,在蚕豆叶片上形成过敏性坏死斑;毒素可导致水稻幼苗萎蔫、胚根胚芽生长受抑和根冠细胞死亡;毒素的毒性与毒素浓度和产毒素菌株的致病力成正比;专化性毒素AT对珍汕97不育系的毒害程度显著高于对保持系的毒害。     

影响麦二叉蚜传播玉米矮花叶病毒效率的因素分析

玉米矮花叶病毒（ＭＤＭＶ）在田间主要依靠介质蚜虫非持久性方式传播,通过麦二叉蚜（Ｓｃｈｉｚａｐｈｉｓｇｒａｍｉｎｕｍ）对ＭＤＭＶ传毒效率影响因素的分析,发现接毒蚜获毒前禁食与否及禁食时间的长短与传毒效率呈高度正相关,从蚜量与传毒效率的关系来看,多头蚜虫的传毒效率均比单头蚜高,随着ＭＤＭＶ浓度和传毒蚜量的增加,传毒效率也随之提高,单蚜获毒１０ｍｉｎ后不禁食其传毒效率最高,随着禁食时间的延长,其传毒效