Serotyping of Avian Mycoplasma Species in India

Two-hundred and two strains of avian mycoplasma species belonging to 10 biotypes were typed serologically by employing disk growth inhibition (DGI) and indirect hemagglutination (IHA) tests. These could be placed into seven serotypes, namely A (80), B (50), C (3), E (34), L (13), P (4), and 1 and R (18). The figures in parentheses show the number of strains within each type. A close relationship was observed between DGI and IHA tests. The IHA test, however, was more sensitive and specific. It was also noticed that biochemically identical biotypes, namely E and G, and B and M were also found identical in serotyping, thus confirming the biochemical identity. In view of these facts, the strains of biotypes M and G were grouped under serotypes B and E, respectively. The antigenic relationships between the serotypes are also discussed.     

Germline Modification and Engineering in Avian Species

Production of genome-edited animals using germline-competent cells and genetic modification tools has provided opportunities for investigation of biological mechanisms in various organisms. The recently reported programmed genome editing technology that can induce gene modification at a target locus in an efficient and precise manner facilitates establishment of animal models. In this regard, the demand for genome-edited avian species, which are some of the most suitable model animals due to their unique embryonic development, has also increased. Furthermore, germline chimera production through long-term culture of chicken primordial germ cells (PGCs) has facilitated research on production of genome-edited chickens. Thus, use of avian germline modification is promising for development of novel avian models for research of disease control and various biological mechanisms. Here, we discuss recent progress in genome modification technology in avian species and its applications and future strategies.     

A New Species of Avian Plasmodium

SYNOPSIS. A new species of avian malaria parasite is described, for which the name Plasmodium formosanum is proposed. It was observed in the blood of Arboriphila crudigularis , the Formosan hill partridge; other bird species in which it may occur remain unknown, as do the mosquito vectors. It produces very broad, elongate gametocytes, the macrogametocyte usually exhibiting a very large vacuole. The usual number of merozoites is eight. The host cell nucleus typically is not displaced, except laterally by the sexual forms. Only the stages occurring in the blood have yet been seen.     

Effect of Species Interaction on Beak Integration in an Avian Hybrid Species Complex

Theory predicts that variability in size and the shape of a morphological trait should often be stable both at the intra- and interspecific level. We studied variation in beak integration among several populations of two species of the genus Passer, a hybrid species, the Italian sparrow (Passer italiae) and one of its parents, the Spanish sparrow (Passer hispaniolensis). We show that the general shape of the beak has been conserved in these two species and that hybrid speciation has had no major effects on beak integration. However, in young, sympatric populations, phenotypic integration between beak height and length decreased significantly, to the extent that these two dimensions apparently became independent. This displacement in phenotypic integration seems to be accompanied with changes in the distribution of phenotypic variation at the univariate level. This suggests that while beak shape may have been constrained over evolutionary time-scales and major hybridization events (i.e. the formation of the hybrid Italian sparrow), under specific selection regimes linked to secondary contact, it can evolve rapidly.     

Noise Pollution Changes Avian Communities and Species Interactions

Humans have drastically changed much of the world's acoustic background with anthropogenic sounds that are markedly different in pitch and amplitude than sounds in most natural habitats [1], [2], [3] and [4]. This novel acoustic background may be detrimental for many species, particularly birds [1]. We evaluated conservation concerns that noise limits bird distributions and reduces nesting success via a natural experiment to isolate the effects of noise from confounding stimuli and to control for the effect of noise on observer detection biases [5]. We show that noise alone reduces nesting species richness and leads to different avian communities. Contrary to expectations, noise indirectly facilitates reproductive success of individuals nesting in noisy areas as a result of the disruption of predator-prey interactions. The higher reproductive success for birds within noisy habitats may be a previously unrecognized factor contributing to the success of urban-adapted species and the loss of birds less tolerant of noise. Additionally, our findings suggest that noise can have cascading consequences for communities through altered species interactions. Given that noise pollution is becoming ubiquitous throughout much of the world, knowledge of species-specific responses to noise and the cumulative effects of these novel acoustics may be crucial to understanding and managing human-altered landscapes.     

东北山地次生林鸟类多样性的研究

山地次生林是东北地区半山区重要的生态环境。随着森林的采伐,次生林越来越多,与人类的关系也越来越密切。有关次生林鸟类多样性的研究,国内报道甚少。我们于1983—1984年4—7月在吉林省蛟     

The Worldwide Variation in Avian Clutch Size across Species and Space

Traits such as clutch size vary markedly across species and environmental gradients but have usually been investigated from either a comparative or a geographic perspective, respectively. We analyzed the global variation in clutch size across 5,290 bird species, excluding brood parasites and pelagic species. We integrated intrinsic (morphological, behavioural), extrinsic (environmental), and phylogenetic effects in a combined model that predicts up to 68% of the interspecific variation in clutch size. We then applied the same species-level model to predict mean clutch size across 2,521 assemblages worldwide and found that it explains the observed eco-geographic pattern very well. Clutches are consistently largest in cavity nesters and in species occupying seasonal environments, highlighting the importance of offspring and adult mortality that is jointly expressed in intrinsic and extrinsic correlates. The findings offer a conceptual bridge between macroecology and comparative biology and provide a global and integrative understanding of the eco-geographic and cross-species variation in a core life-history trait.     

Emergence of a Novel Avian Pox Disease in British Tit Species

Avian pox is a viral disease with a wide host range. In Great Britain, avian pox in birds of the Paridae family was first diagnosed in a great tit (Parus major) from south-east England in 2006. An increasing number of avian pox incidents in Paridae have been reported each year since, indicative of an emergent infection. Here, we utilise a database of opportunistic reports of garden bird mortality and morbidity to analyse spatial and temporal patterns of suspected avian pox throughout Great Britain, 2006–2010. Reports of affected Paridae (211 incidents) outnumbered reports in non-Paridae (91 incidents). The majority (90%) of Paridae incidents involved great tits. Paridae pox incidents were more likely to involve multiple individuals (77.3%) than were incidents in non-Paridae hosts (31.9%). Unlike the small wart-like lesions usually seen in non-Paridae with avian pox in Great Britain, lesions in Paridae were frequently large, often with an ulcerated surface and caseous core. Spatial analyses revealed strong clustering of suspected avian pox incidents involving Paridae hosts, but only weak, inconsistent clustering of incidents involving non-Paridae hosts. There was no spatial association between Paridae and non-Paridae incidents. We documented significant spatial spread of Paridae pox from an origin in south-east England; no spatial spread was evident for non-Paridae pox. For both host clades, there was an annual peak of reports in August/September. Sequencing of the avian poxvirus 4b core protein produced an identical viral sequence from each of 20 great tits tested from Great Britain. This sequence was identical to that from great tits from central Europe and Scandinavia. In contrast, sequence variation was evident amongst virus tested from 17 non-Paridae hosts of 5 species. Our findings show Paridae pox to be an emerging infectious disease in wild birds in Great Britain, apparently originating from viral incursion from central Europe or Scandinavia.     

Agroforestry Systems as Habitat for Avian Species: Assessing Its Role in Conservation

In the current scenario of rapid conversion of tropical forests into human-dominated activities landscape, the present study was undertaken to understand the role of existing agroforestry systems in conservation of avian species. Three types of agroforestry systems namely tea gardens, homegardens and agrisilviculture were selected in the Brahmaputra North Bank Landscape of Assam, northeast India for the study. A total of 468 point counts revealed 164 bird species belonging to 51 families and 18 orders across all the three different types of agroforestry systems. Tea gardens showed significantly higher bird species richness followed by homegardens and agrisilviculture systems. As per IUCN, four species were categorized as Near Threatened and one species was categorized as Vulnerable. Out of 164 species recorded, 68.3% species were residents, 30.5% species were winter visitors and remaining were summer visitors (1.2%). Majority of the species (45.7%) were common to all the three types of selected agroforestry systems. The feeding guilds revealed that most of the species were insectivorous (50.0%) in habit. A total of 167 tree species belonging to 54 families and 24 orders was recorded across all the three different types of agroforestry systems. The highest tree species richness was recorded in the homegardens (160), followed by agrisilviculture systems (19) and least in tea gardens (11). No statistically significant correlation was found among bird species richness and patch size, tree species richness and number of bird species individuals. The selected agroforestry systems have provided shelter, nesting space, feeding and foraging grounds for birds during the winter season. This data can be useful for the policy makers, tea garden managers, homegarden owners for framing conservation policies of avian species in an era of natural wildlife habitat loss and degradation.     

Tissue Distribution,Gender- and Genotype-Dependent Expression of Autophagy-Related Genes in Avian Species

As a result of the genetic selection of broiler (meat-type breeders) chickens for enhanced growth rate and lower feed conversion ratio, it has become necessary to restrict feed intake. When broilers are fed ad libitum, they would become obese and suffer from several health-related problems. A vital adaptation to starvation is autophagy, a self-eating mechanism for recycling cellular constituents. The autophagy pathway has witnessed dramatic growth in the last few years and extensively studied in yeast and mammals however, there is a paucity of information in avian (non-mammalian) species. Here we characterized several genes involved in autophagosome initiation and elongation in Red Jungle fowl (Gallus gallus) and Japanese quail (coturnix coturnix Japonica). Both complexes are ubiquitously expressed in chicken and quail tissues (liver, leg and breast muscle, brain, gizzard, intestine, heart, lung, kidney, adipose tissue, ovary and testis). Alignment analysis showed high similarity (50.7 to 91.5%) between chicken autophagy-related genes and their mammalian orthologs. Phylogenetic analysis demonstrated that the evolutionary relationship between autophagy genes is consistent with the consensus view of vertebrate evolution. Interestingly, the expression of autophagy-related genes is tissue- and gender- dependent. Furthermore, using two experimental male quail lines divergently selected over 40 generations for low (resistant, R) or high (sensitive, S) stress response, we found that the expression of most studied genes are higher in R compared to S line. Together our results indicate that the autophagy pathway is a key molecular signature exhibited gender specific differences and likely plays an important role in response to stress in avian species.     

Seroepidemiologic Survey of Potential Pathogens in Obligate and Facultative Scavenging Avian Species in California

Throughout the world, populations of scavenger birds are declining rapidly with some populations already on the brink of extinction. Much of the current research into the factors contributing to these declines has focused on exposure to drug residues, lead, and other toxins. Despite increased monitoring of these declining populations, little is known about infectious diseases affecting scavenger bird species. To assess potential infectious disease risks to both obligate and facultative scavenger bird species, we performed a serosurvey for eleven potential pathogens in three species of scavenging birds in California: the California condor (Gymnogyps californianus), turkey vulture (Cathartes aura) and golden eagle (Aquila chrysaetos). California condors were seropositive for avian adenovirus, infectious bronchitis virus, Mycoplasma gallisepticum, avian paramyxovirus-2, West Nile virus (WNV) and Toxoplasma gondii. Golden eagles were seropositive for avian adenovirus, Chlamydophila psittaci and Toxoplasma gondii, and turkey vultures were seropositive for avian adenovirus, Chlamydophila psittaci, avian paramyxovirus-1, Toxoplasma gondii and WNV. Risk factor analyses indicated that rearing site and original release location were significantly associated with a positive serologic titer to WNV among free-flying condors. This study provides preliminary baseline data on infectious disease exposure in these populations for aiding in early disease detection and provides potentially critical information for conservation of the endangered California condor as it continues to expand its range and encounter new infectious disease threats.     

禽流感与猪流感病毒：跨越物种传播的新认识

今年在墨西哥暴发的流感疫情来源于一种新的流感病毒：甲型H1N1病毒．这种病毒包括人源,禽源和猪源等甲型流感病毒基因片段,为混合毒株．比较了禽、猪和人的流感病毒在其天然宿主中的致病机理,主要目的是评估猪和禽的流感病毒成为人兽共患病的可能性,同时还评估猪在禽流感病毒传入人的过程中可能起到的作用．禽流感和猪流感作为人畜共患疾病,在流感病毒从动物到人的传播过程中起到关键的作用．猪作为流感病毒的中间宿主,具有混合器作用,人、猪、禽流感病毒可在其体内进行基因重排产生新病毒,并可能跨越种间屏障感染人类．但是流感病毒本身的跨越种间障碍传播不足以引起人流感的大暴发,动物流感病毒必须经过显著的遗传变异后才能使其在人群中长期存在．     

禽Ⅰ型副粘病毒各种禽源分离株毒力及其相关基因的研究

用测定新城疫病毒(NDV)毒力的经典方法,即鸡胚平均死亡时间(MDT)和脑内接种致病指数(ICPI),对源于鸡、鸽、鹅、珍珠鸡、孔雀、鹌鹑和画眉鸟等7种禽(鸟)源的共14个禽Ⅰ型副粘病毒(APMV-1)广西分离株,分别测定了毒力。同时对分离株F基因的N一端前段和HN基因的e末端片段进行扩增、测序和分析,并绘制系谱树。结果发现,分离株的MDT在36h～75h之间,除1株鸽源毒株gxp22的ICPI值为0外,其余分离株在1．09～1．95之间;除孔雀源的分离株gxpc52在F基因裂解位点附近的氨基酸序列为^112R-RQ-R-R-F^117之外,其它13株均为^112R-R-Q-K-R-F^117,都符合强毒株的特征。所有分离株与国内参考强毒株F48E8和国外参考强毒株HER／33在HN基因e末端终止密码子的位置相同,也符合强毒株的特征。根据F基因核苷酸序列绘制的系谱树发现,近几年来在广西流行的APMV-1毒株的基因型为Ⅶd亚型;根据HN基因核苷酸序列绘制的系谱树表明,广西各种禽源APMV-1分离株可分为2个群。研究的结果表明,根据F基因裂解位点附近的氨基酸序列和HN蛋白翻译的终止密码子的位置判定APMV-1毒力的结果,都与毒株在临床上的致病情况相符。因此,根据F基因和HN基因序列和结构的特征,均可以判定APMV-1临床分离株的体内致病性。     

Nonconserved Tryptophan 38 of the Cell Surface Receptor for Subgroup J Avian Leukosis Virus Discriminates Sensitive from Resistant Avian Species

Subgroup J avian leukosis virus (ALV-J) is unique among the avian sarcoma and leukosis viruses in using the multimembrane-spanning cell surface protein Na⁺/H⁺ exchanger type 1 (NHE1) as a receptor. The precise localization of amino acids critical for NHE1 receptor activity is key in understanding the virus-receptor interaction and potential interference with virus entry. Because no resistant chicken lines have been described until now, we compared the NHE1 amino acid sequences from permissive and resistant galliform species. In all resistant species, the deletion or substitution of W38 within the first extracellular loop was observed either alone or in the presence of other incidental amino acid changes. Using the ectopic expression of wild-type or mutated chicken NHE1 in resistant cells and infection with a reporter recombinant retrovirus of subgroup J specificity, we studied the effect of individual mutations on the NHE1 receptor capacity. We suggest that the absence of W38 abrogates binding of the subgroup J envelope glycoprotein to ALV-J-resistant cells. Altogether, we describe the functional importance of W38 for virus entry and conclude that natural polymorphisms in NHE1 can be a source of host resistance to ALV-J.     

Prioritizing Avian Species for Their Risk of Population-Level Consequences from Wind Energy Development

Recent growth in the wind energy industry has increased concerns about its impacts on wildlife populations. Direct impacts of wind energy include bird and bat collisions with turbines whereas indirect impacts include changes in wildlife habitat and behavior. Although many species may withstand these effects, species that are long-lived with low rates of reproduction, have specialized habitat preferences, or are attracted to turbines may be more prone to declines in population abundance. We developed a prioritization system to identify the avian species most likely to experience population declines from wind facilities based on their current conservation status and their expected risk from turbines. We developed 3 metrics of turbine risk that incorporate data on collision fatalities at wind facilities, population size, life history, species’ distributions relative to turbine locations, number of suitable habitat types, and species’ conservation status. We calculated at least 1 measure of turbine risk for 428 avian species that breed in the United States. We then simulated 100,000 random sets of cutoff criteria (i.e., the metric values used to assign species to different priority categories) for each turbine risk metric and for conservation status. For each set of criteria, we assigned each species a priority score and calculated the average priority score across all sets of criteria. Our prioritization system highlights both species that could potentially experience population decline caused by wind energy and species at low risk of population decline. For instance, several birds of prey, such as the long-eared owl, ferruginous hawk, Swainson’s hawk, and golden eagle, were at relatively high risk of population decline across a wide variety of cutoff values, whereas many passerines were at relatively low risk of decline. This prioritization system is a first step that will help researchers, conservationists, managers, and industry target future study and management activity.     

采煤沉陷对鸟类群落组成及多样性的影响

采煤沉陷改变了地貌景观,使鸟类的生境发生变化,进而影响鸟类群落多样性。我们于2013年11月—2014年10月在安徽省淮南潘集的采煤沉陷区不同沉陷程度的4种生境开展鸟类调查,研究采煤沉陷导致的生境变化对鸟类群落结构的影响。共记录到鸟类13目29科79种,其中留鸟32种(40.5%),冬候鸟19种(24.1%),夏候鸟25种(31.6%),优势种为灰椋鸟Sturnus cineraceus、喜鹊Pica pica、麻雀Passer montanus和家燕Hirundo rustica。随着采煤沉陷程度的增加,物种数、个体数量、群落密度表现出轻度沉陷区<中度沉陷区<重度沉陷区的规律,多样性指数为轻度沉陷区<重度沉陷区<中度沉陷区,在地表沉陷过程中,鸟类群落结构具有不稳定性。各类生境中鸟类群落的物种组成变化明显,随着沉陷程度的增加,鸟类群落物种丰富度增加。     

Adaptation of Avian Influenza A Virus Polymerase in Mammals To Overcome the Host Species Barrier

Avian influenza A viruses, such as the highly pathogenic avian H5N1 viruses, sporadically enter the human population but often do not transmit between individuals. In rare cases, however, they establish a new lineage in humans. In addition to well-characterized barriers to cell entry, one major hurdle which avian viruses must overcome is their poor polymerase activity in human cells. There is compelling evidence that these viruses overcome this obstacle by acquiring adaptive mutations in the polymerase subunits PB1, PB2, and PA and the nucleoprotein (NP) as well as in the novel polymerase cofactor nuclear export protein (NEP). Recent findings suggest that synthesis of the viral genome may represent the major defect of avian polymerases in human cells. While the precise mechanisms remain to be unveiled, it appears that a broad spectrum of polymerase adaptive mutations can act collectively to overcome this defect. Thus, identification and monitoring of emerging adaptive mutations that further increase polymerase activity in human cells are critical to estimate the pandemic potential of avian viruses.     

非环境类因子对物种数目协同变化的影响

不同分类类群的物种数目常在空间上表现出显著相关地协同变化,但哪些相关系数之间存在较大的差异？究竟是什么因素导致了这种差异是值得关注的问题。从不同作者的研究方法和数据来源来看,不同研究中的研究方法、研究区域和环境条件本身就存在着差异。除以上影响因子外,我们分析了非环境类因子对物种数目协同变化的影响。结果发现分类类群间的物种数量协同变化差异明显,只有起源和生境要求相似的类群间呈显著性相关;不同鸟兽间的协同变化不存在面积效应,但是空间尺度间的相关性差异明显：物种分布型中东洋型物种的协同变化明显,而广布型和古北型不明显;在鸟类居留型中繁殖鸟与兽类的协同变化极为显著,而其他类型则不显著。综上所述,物种数量协同变化的非环境类影响因子中,生态类型和起源对分类类群间的物种数目协同关系有重要影响,