雏鸡沙门氏菌病的病原分离与鉴定

邯郸地区某县养殖场于2008年2月引进一批海兰白雏鸡共6500只,4日龄时部分雏鸡开始发病,6日龄时开始死亡,7d内共死亡1248只,死亡率达19.2%。剖检不同日龄死雏21只,活病雏13只,死雏呈现严重败血症病变,活雏心肌、肝、肺、肌胃等脏器出现黄白色或大小不等的灰白色坏死灶。取其卵黄、肝、脾、心血等病料进行病原分离培养,从获得的153个菌落中挑选可疑菌落27个,经细菌学鉴定,确认17株为鸡白痢沙门氏菌,抗原式为1,9,12∶-∶-,10株为德尔卑沙门氏菌(S.derby),抗原式为1,4,12∶f,g∶-。     

Disease Law and Forecasting of the Needle Blight ofPinus sylvestris var. mongolica

IntroductionNeedleblightofPinussylvcsIrisvarmongolicaisoneofthemaindiseaseonPinus3:VlvesIrlAvar.mongolicawhichisanativesPeciesinthearcabetWecnHulunbcirgrasslandandforest.Thisdiscaseisnotcdforscriousinfestation,fastspreadanddifficulttobecontrolled.Inthepas…     

Global parasite and Rattus rodent invasions: The consequences for rodent‐borne diseases

We summarize the current knowledge on parasitism‐related invasion processes of the globally invasive Rattus lineages, originating from Asia, and how these invasions have impacted the local epidemiology of rodent‐borne diseases. Parasites play an important role in the invasion processes and successes of their hosts through multiple biological mechanisms such as “parasite release,” “immunocompetence advantage,” “biotic resistance” and “novel weapon.” Parasites may also greatly increase the impact of invasions by spillover of parasites and other pathogens, introduced with invasive hosts, into new hosts, potentially leading to novel emerging diseases. Another potential impact is the ability of the invader to amplify local parasites by spillback. In both cases, local fauna and humans may be exposed to new health risks, which may decrease biodiversity and potentially cause increases in human morbidity and mortality. Here we review the current knowledge on these processes and propose some research priorities.     

陕西榆林山药根腐病病原菌的分离与鉴定

旨在明确引起陕西省榆林市山药根腐病的致病菌,为该地区山药根腐病的防治提供参考。以受害山药块茎和根际土壤为试验材料,通过组织分离法获得纯培养,结合柯赫氏法则、形态学鉴定、ITS区序列分子生物学鉴定,以及构建系统发育树和序列比对的方法,明确山药根腐病的致病菌。结果表明,引起陕西榆林山药根腐病的病原菌为棕黑腐质霉、燕麦镰孢和尖孢镰孢。陕西榆林山药根腐病由腐质霉属和镰孢属两个属的3种病原菌引起,棕黑腐质霉是首次报道危害山药,镰孢属真菌是该地区山药根腐病的主要致病菌。     

Effects of natural barriers on the spillover of a marine mollusc: implications for fisheries reserves

• 1. The movement of organisms and dispersal of propagules is fundamental to the maintenance of populations over time. However, the existence of barriers, created through the spatial configuration of habitats, may significantly affect dispersal patterns and thus influence community dynamics and resource sustainability.
• 2. Within marine environments unstructured or open habitats may form partial or complete ecological barriers due to elevated risk of predation or physical stresses associated with them. The existence and effects of such barriers may be of particular importance when considering the establishment of marine protected areas with a fisheries enhancement focus.
• 3. In this paper, the spillover of post‐settlement queen conch (Strombus gigas) from a protected area in the Turks and Caicos Islands is investigated. It is hypothesized that the reserve boundaries overlap with a series of shallow, sand habitats that effectively enclose the protected population, reducing the spillover of conch into the adjacent fished areas.
• 4. To test this, density gradient maps for juvenile and adult conch populations were constructed using underwater visual survey data at 68 sites within and surrounding the protected area. These maps illustrate very low densities coinciding with poor, shallow sand habitats along the two marine boundaries of the reserve where spillover is expected to take place.
• 5. These sand habitats are thought to create ecological barriers to a slow, sedentary gastropod largely due to their shallowness (physical stresses of solar exposure or anoxia) and lack of food reducing the tendency of individuals to move across these areas, despite the 10‐times higher density of adult queen conch observed in the protected area compared with outside.

Copyright © 2003 John Wiley & Sons, Ltd.     

Spillover effects of a Mediterranean marine protected area on the European spiny lobster Palinurus elephas (Fabricius, 1787) resource

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黑龙江省露地西瓜细菌性果斑病病原菌的分离与鉴定

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利用品种混合控制小麦病害的研究进展

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