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.     

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.     

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...     

An imperfect imago? Post-mating loss of iridescent scales in Cheimas butterflies may change female from attractive to cryptic (Lepidoptera: Nymphalidae: Satyrinae)

Adults of both sexes of Cheimas opalinus (Staudinger), a Satyrinae butterfly occurring in the cloud forests of the Venezuelan Cordillera de Mérida, have simple wing colour patterns, dark brown dorsa marked by one conspicuous element, large greenish-blue patches in the discal area of the hind wing. It was observed that in young, freshly emerged females these patches are frequently absent. They fade away and eventually disappear during mating and nuptial flights when brushed out by lateral movements of the male’s hind wing put between folded female hind wings. The falling off of the scales is made easy because they do not adhere to the wing as firmly as brown background scales due to their particular folded extremities. We speculate that this process is related to the fitness of the females. Prior to mating, blue-green patches are advantageous because they attract the attention of the opposite sex and enhance the chances of successful mating. After mating they lose their sexual role. Females without the blue-green patches become cryptic. Thus, they are less apparent not only for the males, which helps them avoid sexual harassment, but also for potential bird predators. Additionally, the loss of blue reflecting scales may speed up the warming up of the abdomen and egg maturation. In the males, positive role of the patches (signalling), and negative (bird attraction), is balanced during their entire life span, and they fade gradually due to regular usage of wings scaling in flight. Our hypothesis is supported by morphological, optical, experimental and statistical analysis in which we used 509 individuals of both sexes. A similar ratio of young (with undamaged wing) females with or without blue patch was recorded, whereas in the males no individuals without any trace of blue patch were reported, and a correlation of age (wing damage) and gradual fading off of the patch was demonstrated. Such an adaptation involving an active change of the appearance of adults, i.e. colour patterns related to sexual selection, has not been reported previously in Lepidoptera.     

禽流感流行与防制现状

禽流感是禽的烈性传染病，对养禽业造成严重危害，同时威胁着人类的健康．本文对国内外禽流感近年来的流行情况、禽流感病毒的特征及危害、临床症状和病理变化、禽流感的诊断技术和防治进行了综述．     

New species of Leucocytozoon from the avian families Otidae,Podargidae and Threskiornithidae

Leucocytozoon otidis n. sp., Leucocytozoon podargii n. sp. and Leucocytozoon ibisi n. sp. are described from bustards, tawny frogmouth and ibis, respectively. Relevant differentiating morphological characteristics are presented and endogenous stages are also described for L. podargii.     

兔圆小囊抗菌肽对鸡新城疫病毒及禽流感病毒血清抗体水平影响的研究

选择90只1日龄星杂蛋鸡随机分为两组,实验组在7、14、21、28、35、42、49日龄时分别胸肌注射无菌处理过的兔圆小囊抗菌肽0.1、0.2、0.3、0.4、0.5、0.5、0.5mg,对照组同时分别注射相同体积的灭菌生理盐水。常规免疫后,分别于第7、14、21、28、35、42、56日龄采血分离血清,实验组及对照组均随机抽取10只鸡的血清进行血凝抑制实验(HI),分别测定NDV和AIV血清抗体的血凝抑制效价。结果显示:实验组NDV和AIV血清抗体水平均明显高于对照组(P<0.01)。表明兔圆小囊抗菌肽可显著提高鸡新城疫弱毒苗及禽流感灭活苗的抗体水平。