The behaviour of Cotinis nitida Linnaeus,the green June beetle (Coleoptera: Scarabaeidae), on mowed lawns makes them especially vulnerable to bird predators

ABSTRACT

Males of the green June beetle Cotinis nitida are regularly attacked by birds as they search for females on lawns but which bird species feeds on the beetle changes from year to year. In 2018 for the first time on a farm in northern Virginia, brown thrashers (Toxostomum rufum) joined blue jays (Cyanocitta cristata) as major predators of the beetles. The two species employed very different tactics when hunting for June beetles, with the thrashers searching while walking forward on the mowed lawn while the jays scanned for beetles when perched in trees about the lawn. The beetles became very scarce at the lawn in early July in 2017 and 2018 and their predators apparently moved elsewhere. Subsequently, male beetles were occasionally observed patrolling a nearby hayfield in search of mates with rare copulations recorded after July 15. Because predatory birds could not exploit the beetles in the tall grass of the hayfield it seems likely that the mowed lawn constituted an evolutionarily novel ecological trap which made searching beetles conspicuous and easily captured by beetle-hunting birds.     

《腊叶》:对生命的本真书写

《野草》中的《腊叶》较为真实地展现了鲁迅本人对生命的思考。"病叶"意象是鲁迅对生命的大欢喜、大悲痛体验后的平易的情感投射,是回归到生命本体的真实书写。"病叶"的疾病隐喻与鲁迅本人的疾病体验有着密切联系",病"的生命体验促使他对生命有着更加真切的看法。     

禽白血病研究进展

禽白血病(AL)是由病毒引起的一种肿瘤性传染病,感染率高,发病率低,是危害养鸡业的主要疾病之一[1].本文主要介绍了其病原学、流行病学、诊断、预防等几个方面的研究近况,旨在加强对禽白血病的防制.     

应用负压隔离器和SPF鸡制备特异性高免禽类抗血清

负压隔离器是目前国外广泛用于动物实验的先进设备。其优点是能保证实验结果的可靠性。提高实验水平并能防止污染环境。我国最近才从国外引进了这一先进设备应用于动物实验,取得了一些成果。我们应用负压隔离器和SPF鸡制备高质量禽类抗血清取得了成功,用12种禽类抗原测定了抗血清的特异性。结果表明抗血清的特异性和滴度均达到了设计要求。完全可以用于各和血清学的诊断和研究。     

A taxonomic review of avian piroplasms of the genus Babesia Starcovici, 1893 (Apicomplexa: Piroplasmorida: Babesiidae)

The validity of avian species of Babesia is reviewed and 13 species recognized. Slides from records of Babesia in the literature have been re-examined and their status determined. Erroneous published records have been addressed. Previously regarded piroplasms of the genera Babesiosoma and Haemohormidium are reappraised and their relationship to Babesia and the Aegyptianella-Rickettsia group of organisms discussed. Host-specificity, pathogenicity and vectors are also discussed.     

樱桃谷鸭巴氏杆菌病的防治措施

禽巴氏杆菌病是禽类的一种高度接触性传染病.本文介绍了一起病例的发病概况、病理变化、诊断及防治措施.     

ND-EDS二联油乳疫苗免疫对比及田间免疫试验

以自制 ND- EDS二联油苗为主进行免疫试验 ,并以同种二联油苗、ND和 EDS单油苗作对照 ,测定各种疫苗免疫后 ND、EDSHI抗体消涨规律 ,并进行强毒攻击试验。在此基础上 ,用自制二联苗实地免疫产前蛋鸡 2 6 830只 ,进行田间免疫试验。结果表明 :自制二联苗免疫效果良好 ,免疫期为 36 0 d左右 ,免疫期内对 ND和 EDS强毒攻击的保护率分别为 10 0 %和 95.8%     

黄芪多糖对新城疫弱毒疫苗免疫雏鸡血凝抑制抗体水平的影响

40只1日龄健康雏鸡随机分成4组,Ⅰ组为对照组,Ⅱ、Ⅲ、Ⅳ为黄芪多糖试验组,每组10只,置于相同的条件下饲养,在第5日龄时对Ⅱ-Ⅳ组每只鸡分别颈部皮下注射0.1mg、0.3mg和0.5mg黄芪多糖注射液,对照组注射生理盐水,每天1次,连续3d,并于第7和21日龄时采用滴鼻、点眼的方式给各组鸡接种新城疫Lasota弱毒疫苗,用β-微量法检测血清中血凝抑制抗体效价的动态变化。结果表明,黄芪多糖对鸡新城疫免疫效果有明显的促进作用,与对照组(Ⅰ组)差异显著,其中以黄芪多糖0.5 mg/只时为最佳使用剂量。由此可见,黄芪多糖在一定剂量范围内可明显增强对鸡新城疫免疫的效果。     

鸡禽流感母源抗体的消长规律及其免疫效果研究

为探讨科学的鸡禽流感免疫程序,对1～28日龄的土杂肉鸡和罗曼蛋鸡进行禽流感母源抗体检测,以及对雏鸡接种禽流感油乳剂疫苗后的HI抗体水平变化进行了监测。结果表明,两种雏鸡的母源抗体水平在1日龄时均达最高值,然后逐渐下降;肉鸡11日龄后H5、H9抗体滴度分别降低到4.2log2和4.3log2以下;蛋鸡28日龄后H5、H9...     

犬瘟热病毒RT-PCR检测方法的建立与应用

根据Barrett发表的犬瘟热病毒 (CDV)Onderstepoort弱毒株融合蛋白 (F)基因序列 ,设计合成了一对寡聚核苷酸引物 ,并以南京农业大学惠赠的Onderstepoort标准株反转录产物为模板 ,建立了CDV的RT PCR方法 ,并应用于CDV的诊断。结果表明 ,以该对引物 ,只能从CDV ONP标准株反转录产物中扩增出大小为 32 4bp的核苷酸片段 ,与理论设计值大小一致 ,而正常Vero细胞和同为副粘病毒科的新城疫病毒 (NDV)作为对照 ,病毒扩增结果为阴性。RT PCR可检出 1μl作 10 6倍稀释的CDV ONP标准株反转录产物 ,说明其具有很高的敏感性。应用试验结果 ,可从感染CDV犬的组织病料中提取RNA ,反转录产物中也扩增出 32 4bp的核苷酸片段。通过本研究不仅建立了敏感性、特异性好的CDV的RT PCR检测方法 ,也为F基因的克隆和序列测定及表达奠定了基础。