不同产蛋数岩鸽卵巢转录组的SNP分析

为探索岩鸽(Columba livia)产蛋数相关基因及其遗传标记,利用STAR对高产蛋数和低产蛋数岩鸽卵巢组织转录组数据高质量序列与参考基因组进行比对,去除重复序列后利用GATK进行单核苷酸多态性(SNP)筛选,利用VCFtools对SNP质控后进行主成分分析、进化树构建和Fst计算,利用KEGG富集分析SNP所在基因。结果显示,高产蛋组共有SNP数为298957个,低产蛋组共有SNP数为296137个,高产蛋组、低产蛋组共有SNP数为254118个,KEGG分析结果发现,SNP所在基因显著富集在孕酮调节的卵母细胞成熟、卵母细胞减数分裂和代谢等信号通路;高产蛋组和低产蛋组的102个特异SNP分布在14个注释基因上(LOC110357454、KDM5A、PIGS、BNC2、GBF1、SLAIN2、FGD4、DIAPH2、KIF3B、NFIB、EPG5、OSTF1、EMB、ST3GAL3),且富集的信号通路可能与其产蛋能力密切相关。

Avian responses to an extreme weather event:The case of the‘Filomena’snowstorm in Madrid(central Spain)

Cold spells and severe weather may have detrimental effects in wild birds,but owing to the stochastic nature of these events,it is not always possible to measure their impacts.In January 2021,a strong snowstorm known as‘Filomena’affected Spain,mainly the region of Madrid(Central Spain),which was fully covered with snow and suffered freezing temperatures for a fortnight.Using bird surveys conducted in the winter-spring of 2020 and 2021(before and after Filomena)at same locations,we addressed the possible impact of the cold spell in three widespread gamebirds:Wood Pigeon(Columba palumbus),Eurasian Magpie(Pica pica)and Red-legged Partridge(Alectoris rufa).No significant abundance differences were found between years for none of the species and hunting pressure was only significantly reduced for Partridges,hence this species may have been negatively affected by Filomena.Results suggest that in response to Filomena,Pigeons conducted partial migration in search of better conditions,while Magpies aggregated in certain areas of Madrid and Partridges endured the harsh conditions within their home ranges.Our results highlight the importance to alleviate negative impacts of extreme weather events in wild birds through management actions,especially for sedentary species.

鸽蛔虫ITS rDNA的克隆与序列分析

以采自广东省佛山市的鸽蛔虫(Ascaridia columbae)为研究对象,利用保守引物BD1和BD2扩增鸽蛔虫基因组DNA的ITS rDNA片段,对扩增产物进行克隆和序列测定。结果成功扩增出大小为1045bp的ITS rDNA序列。获得的鸽蛔虫的ITS rDNA序列(AC001、AC002)的5.8S rDNA与GenBank收录的鸡蛔虫5.8S rDNA序列(GenBank登录号为AJ001508)相似性分别为95.5%和94.3%,而与澳大利亚鸽蛔虫5.8 S rDNA序列(GenBank登录号为AJ001509)相似性分别为96.8%和95.5%。将获得的序列与蛔目不同科的代表性蛔虫的5.8SrDNA序列进行比对和系统进化分析,结果表明鸽蛔虫与鸡蛔虫处于同一进化分支上,也表明ITS rDNA是蛔虫分子鉴定的有效遗传标记,这对蛔虫分子分类学及分子流行病学的进一步研究打下了基础。

Rapid increase in numbers and change of land-use in two expanding Columbidae species(Columba palumbus and Streptopelia decaocto)in Algeria

Background: Investigating population ecology of urban bird species,particularly the invasive and expending spe?cies,is the key for the success of urban management and planning strategies.Methods: Populations of two Columbidae species,the Woodpigeon(Columba palumbus) and the Eurasian Collared Dove(Streptopelia decaocto),were monitored from 1992 to 2010 in the Algiers Sahel,the Mitidja Plain and surround?ing areas(Northern Algeria).Monitoring of species densities was performed by the mapping?plot method.The foraging flight routes of Woodpigeon and the distribution of Eurasian Collared Dove were assessed by systematic observations.Results: The number of counted birds was statistically constant at first years of the survey,and then increased sig?nificantly,beginning from low numbers,their densities accelerated sharply between 2001 and 2006,then reached to an equilibrium state.The significant increase in Woodpigeon's population could be explained by the reduced hunt?ing pressure and by species adaptation to new food resources provided by nearby agriculture.Indeed,monitoring of flight directions of the species revealed the use of agricultural landscapes and habitats,which is a good indicator explaining adaptation and trophic niche of the species.The occurrence of the Eurasian Collared Dove in Algiers began in 2000.Its density experienced a rapid increase with similar trend pattern as that of Woodpigeon.Its distributional range is confined mainly in suburban environments of the Mitidja Plain.Conclusion: The modifications of habitats,urbanization increase and the lessening of hunting in the Mitidja Plain facilitated the rapid expansion of the Eurasian Collared Dove and Woodpigeon as well contributed to the increase in their numbers over time.

Molecular survey on zoonotic tick—borne bacteria and chlamydiae in feral pigeons(Columba livia domestica)

Objective;To determine the presence of zoonotic tick-borne bacteria in feral pigeons(Columba lixia domestica) from urban areas.Methods:Spleen samples from 84 feral pigeons,found dead with traumatic injuries in urban areas,were examined by PCR to detect DNA of Anaplasma phagocytophilum,Bartonella spp.,Borrelia burgdorferi sensu lato.Coxiella burnetii.Rickettsia spp.,and Chlamydnphila spp.Results:Twenty(23.8%) pigeons were infected by tick-borne agents,in particular 2(2.38%) animals resulted positive for Bartonella spp.,5(5.95%) for Coxiella burnetii.5(5.95%) for Rickettsia spp.,13(15.47%) for Borrelia burgdorferi sensu lato.All birds scored negative for anaplasma phagocytophilum.Moreover,17(20.23%) pigeons were positive for Chlamydophila spp.and among them 10(11.9%) for Chlamydophila psittaci,Mixed infections by two or three agents were detected in 8(9.52%) animals.Conclusions:Feral pigeons living in urban and periurban areas are a hazard for the human health as source of several pathogens.The obtained results confirm pigeons as reservoirs of chlamydial agents and suggest that they may be involved in the epidemiology of zoonotic tick-borne infections too.

Does melanin-based plumage coloration reflect health status of free-living birds in urban environments?

Background:Ecological functions and processes in urban ecosystems are governed by various human activities.City-adapted and city-exploiting animal species are expected to present certain specific behavioral and physiological traits in comparison to city-avoiders or conspecific individual frequenting less urbanized or rural environments.A trait of high importance,the plumage color polymorphism has been selected as the main study model and was correlated with different morphological and physiological parameters to highlight its importance in determining the possible health status of urban Feral Pigeons(Columba livia)in North African urban habitats.Methods:Different body morphometrics,hematological and hemoparasitic parameters were quantified on freeliving Feral Pigeons in urban environments of northern Algeria.Moreover,plumage melanin-based coloration(MBC)was measured and the data collected at the individual scale was correlated with the previous parameters using linear and non-linear modeling approaches.Results:Plumage MBC scores of the sampled Feral Pigeons ranged between 0.3%and 74.8%.Among the 12 morphological traits measured,body weight,tail length and total length were deemed to be positively correlated with MBC.Darker morphs appeared to have more hemoparasites compared to lighter pigeons.Quite the same observation goes with the immunity but with non-linear trends.The number of monocytes and granulocytes increased with the increase in MBC levels in lighter morphs,while pigeons with high MBC scores exhibited negative relationships between MBC levels and the number of white blood cells.Conclusions:Despite the existence of a number of studies demonstrating phenotypic directional selection,further studies are undoubtedly necessary to understand in detail the underlying mechanisms in species life-history strategies between differently colored individuals.Findings of this correlative study open exciting perspectives revealing that MBC can be considered a good indicator of and health status and adaptation strategies to changes in urban environments.

Foraging ecology of the globally threatened Nilgiri Wood Pigeon(Columba elphinstonii)in the Western Ghats,India

Foraging ecology of the globally endangered Nilgiri Wood Pigeon(Columba elphinstonii) was investigated in the Western Ghats,India,using faecal sampling and direct observations.The birds fed on fruits of 39 plant species,on seeds of 11 species,flowers and leaf buds of four species and a few ground invertebrates.Direct observations across seasons showed nine plant species were selected more often(47% of observations),with fruits of the members of the family Lauraceae the most preferred.Gleaning accounted for 76% of feeding methods throughout the year.Feeding was mainly from twigs at the edges on the upper and middle canopy(> 6 m).Frequency of feeding on fruits correlated significantly with fruit abundance,which depended on rainfall.The present study indicates that the pigeon requires a wide variety of diets from different forest environments.Conservation of this species depends on preserving all habitat types required to meet their resource needs throughout the year.

Prevalence of Decreased Susceptibility of Cryptococcus spp. Isolates to Fluconazole in Urban Sources of Presidente Prudente

The genus Cryptococcus is composed of encapsulated yeasts that have the ability to infect and cause disease in humans, as Cryptococcus gattii/Cryptococcus neoformans species complex. Facing the current research panel, few studies about cryptococcosis and epidemiological data have been carded out in the western region of Sao Paulo state. This study aimed to verify the occurrence of Cryptococcus spp. In public areas of the city of Presidente Prudente, using pigeon droppings and tree hollows as an environmental source. The samples were identified by conventional mycological methods. Were collected 54 samples from pigeon droppings and 62 samples from tree hollows of the genus Licania. And of these samples, 47 （87.0%） and 14 （22.5%） had positive growth of yeast from pigeon droppings and tree hollows, respectively. Cryptococcus was identified in 11 （20.4%） of the samples from pigeon droppings and 3 （21.4%） of those from tree hollows. The following species were identified： Cryptococcus neoformans （7.15%）, Cryptococcus laurentti （14.28%）, and Cryptococcus albidus （78.57%）. Decreased susceptibility to fluconazole was observed for some isolates. Fluconazole exhibited a limited in vitro activity, particularly against Cryptococcus albidus and Cryptococcus laurentii. Identification and susceptibility testing of Cryptococcus spp. should be performed on a routine basis in view of their unpredictable susceptibility profiles.

Modulating Motor Behaviors by Electrical Stimulation of Specific Nuclei in Pigeons

Pigeons （Columba livia） have excellent flying and orienting abilities and are ideal study subjects for biologists who re- search the underlying neurological mechanisms that modulate flying and allow birds to find their way home. These mechanisms also attract the engineers who want to apply pigeon locomotion to the design of flying robots. Here, we identified the mo- tor-related brain nuclei and revealed their relationship in spatial distribution in pigeons under light anesthesia and freely moving conditions respectively. Flapping and lateral body movements were successfully elicited when electrical microstimulation was applied to the diencephalon, medial part of the midbrain, and medulla oblongata of lightly anesthetized pigeons （N = 28） whose heads were fixed. The current thresholds for stimulating different nuclei and behavior ranged from 10 pA to 20 ~tA. During freely moving tests （N = 24）, taking off and turning were induced by a wireless stimulator through microelectrodes implanted in specific nuclei or brain regions. The results showed that electrical stimulation of these nuclei elicited the desired motor behavior. In addition, regulatory mechanisms were identified in the motor-related regions and nuclei of pigeons. Overlapping in the behavior elicited by stimulation of different regions indicates that complicated neural networks regulate motor behavior. Therefore, more studies need to be conducted involving simultaneous stimulation at multiple points within the nuclei involved in the networks.

PROJECTIONS FROM HERBST CORPUSCLES TO SPINAL CORD IN PIGEON (Columba livia) AS REVEALED BY HORSERADISH PEROXIDASE

Birds have well-developed ability to detect weak vibrational disturbances of the ground or perch. Recent electrophysiological studies have demonstrated that vibration sensitive receptors could be the Herbst corpuscles, which are only found in birds, widely distributed in such regions as the beak, dermis and interosseous membrane between the tibia and fibula. Their structures and functions are similar to those of mammailin Pacinian corpuscles.

Effects of human disturbance on nest placement of the woodpigeon (Columba palumbus): a case study from the Middle Atlas, Morocco

The woodpigeon(Columba palumbus)is a common and widespread bird in Morocco(North Africa).I exam­ined,over 2 years(2010 and 2011),the breeding density and nest placement of this game species in relation to nest site habitat and degree of human disturbance.The study area was in the Middle Atlas Tighboula moun­tain forest,Morocco,in a disturbed and an undisturbed site.Using data collected in the 2 study sites,I aimed to identify the factors influencing the placement of nests within holm oak trees(Quercus rotundifolia)and their densities.I found that habitat structures,influenced by grazing disturbance,have affected nesting density and the location of nests of this species.Woodpigeons place their nests in a higher position(3.42±0.19 m)when disturbance intensity is high and lower(1.68±0.1 m)when disturbance intensity is low,and show higher nest­ing density in less disturbed zone(3.1±0.4 nests/ha)than in highly disturbed zones(1.4±0.2 nests/ha).Graz­ing disturbance could pose a threat to population persistence at a broader scale and could potentially reduce the abundance of this species by altering the composition and the structure of the forest nesting habitat.Further multi-scale studies are needed to assess the effects of different levels of grazing disturbance on woodpigeon nest density and placement,and to enhance our knowledge of the breeding behavior of this game species under vari­able environments.

Detection of Chlamydophila psittaci from feral pigeons in environmental samples:problems with currently available techniques

Chlamydophila psittaci(Lillie,1930)Everett et al.,1999,the pathogenic agent of human ornithosis,is widespreadin feral pigeon populations and many cases of transmission from feral pigeons to humans have been reported.Theaim of the present study was to detect C.psittaci in environmental samples to find out more about possibletransmission routes and,therefore,to assess the zoonotic risk for humans.Fecal samples were collected from nestboxes in a feral pigeon loft.Additionally,samples were taken from the feather dust film covering the water surface ofpublic fountains where pigeons regularly bathe.The samples were tested for the presence of chlamydial antigenusing an antigen enzyme-linked immunosorbent assay to prove shedding of C.psittaci by feral pigeons.This testdetects a genus specific lipopolysaccharide in the outer membrane of the chlamydial bacteria.Samples were testedusing the IDEIA PCE Chlamydia Test kit(DakoCytomation)and positive results were verified with IDEIA ChlamydiaBlocking Reagents(DakoCytomation).The IDEIA PCE Chlamydia Test yields a high proportion of positive results.However,when IDEIA Chlamydia Blocking was performed,most of the positive results turned out to be negative orcould not be interpreted.We conclude that antigen-enzyme-linked immunosorbent assay tests are not suitable fordetecting C.psittaci in environmental samples.Previous publications where no blocking test was used should bereconsidered critically.