maximum running speed of captive bar-headed geese is unaffected by severe hypoxia.while bar-headed geese are renowned for migration at high altitude over the himalayas, previous work on captive birds suggested that these geese are unable to maintain rates of oxygen consumption while running in severely hypoxic conditions. to investigate this paradox, we re-examined the running performance and heart rates of bar-headed geese and barnacle geese (a low altitude species) during exercise in hypoxia. bar-headed geese (nā€Š=ā€Š7) were able to run at maximum speeds (determined in normoxi ...201424710001
global transcriptome analysis of h5n1 influenza virus-infected human cells.influenza a virus (iav) belongs to the orthomyxoviridae family. iav causes a highly contagious respiratory disease in humans that exacts severe economic losses globally. the virus uses strategies developed to exploit and subvert cellular proteins and pathways to increase its own replication and to inhibit antiviral immune response.201930774581
new evidence for the east-west spread of the highly pathogenic avian influenza h5n1 virus between central asian and east asian-australasian flyways in china.the spread of highly pathogenic avian influenza (hpai) h5n1 virus is associated with wild fowl migration in east asian-australasian (ea) and central asian (ca) flyways. however, the spread of h5n1 virus between the two flyways is still unclear. here, the movements of wild waterfowl were obtained from satellite tracking data covering seven bar-headed geese and three great black-headed gulls breeding in the qinghai lake area (along the ea flyway), and 20 whooper swans wintering in the sanmenxia re ...201931164049
parakeet hemoglobin - its crystal structure and oxygen affinity in relation to some avian hemoglobins.background "avians" often show efficient oxygen management to meet the demands of their metabolism. hemoglobin, a transporter protein consists of four non-covalently linked subunits contain haem binding hydrophobic pocket serves as a site of allosteric cooperativity. the physiology and anatomy of both mammals and avian are functionally different, in birds, the respiratory system formed by small air sacs that serve as tidal ventilation for the lungs and have no significant exchange across their c ...202032196438
allosteric mechanisms underlying the adaptive increase in hemoglobin-oxygen affinity of the bar-headed goose.the high blood-o2 affinity of the bar-headed goose (anser indicus) is an integral component of the biochemical and physiological adaptations that allow this hypoxia-tolerant species to undertake migratory flights over the himalayas. the high blood-o2 affinity of this species was originally attributed to a single amino acid substitution of the major hemoglobin (hb) isoform, hba, which was thought to destabilize the low-affinity t state, thereby shifting the t-r allosteric equilibrium towards the ...201830026237
comparative analyses of the gut microbiota among three different wild geese species in the genus this study, we characterized for the first time the gut microbiota of greylag geese (anser anser) using high-throughput 16s rrna gene sequencing technology. the results showed that the phyla firmicutes (78.55%), fusobacteria (9.38%), proteobacteria (7.55%), bacteroidetes (1.82%), cyanobacteria (1.44%), and actinobacteria (0.61%) dominated the gut microbial communities in the greylag geese. then, the variations of gut microbial community structures and functions among the three geese species, ...201829668076
first de novo whole genome sequencing and assembly of the bar-headed goose.the bar-headed goose (anser indicus) mainly inhabits the plateau wetlands of asia. as a specialized high-altitude species, bar-headed geese can migrate between south and central asia and annually fly twice over the himalayan mountains along the central asian flyway. the physiological, biochemical and behavioral adaptations of bar-headed geese to high-altitude living and flying have raised much interest. however, to date, there is still no genome assembly information publicly available for bar-he ...202032292659
correction: tackling the tibetan plateau in a down suit: insights into thermoregulation by bar-headed geese during migration. 202032769160
vigilance strategy differentiation between sympatric threatened and common crane species.studies have indicated that threatened species may show reduced or elevated antipredator behavior compared with their close common relatives, but remarkably few studies revealed such differences in behavior among populations. exploring factors affecting behavior between phylogenetically related common and threatened species could help understand such discrepancy. we tested for effects of external and internal variables including month, time of day, habitat type, distribution area, group composit ...202032360312
a morphometric analysis of the lungs of high-altitude ducks and geese.we examined the morphology of the lungs of five species of high-altitude resident ducks from lake titicaca in the peruvian andes (yellow-billed pintail [anas georgica], cinnamon teal [anas cyanoptera orinomus], puna teal [anas puna], speckled teal [anas flavirostris oxyptera], and ruddy duck [oxyura jamaicensis ferruginea]) and compared them with those of the high-altitude migratory bar-headed goose (anser indicus) and the low-altitude migratory barnacle goose (branta leucopsis). we then determi ...202032173858
cardiovascular responses to progressive hypoxia in ducks native to high altitude in the andes.the cardiovascular system is critical for delivering o2 to tissues. here, we examined the cardiovascular responses to progressive hypoxia in four high-altitude andean duck species compared with four related low-altitude populations in north america, tested at their native altitude. ducks were exposed to stepwise decreases in inspired partial pressure of o2 while we monitored heart rate, o2 consumption rate, blood o2 saturation, haematocrit (hct) and blood haemoglobin (hb) concentration. we calcu ...202032041807
characterization of the microbiome along the gastrointestinal tracts of semi-artificially reared bar-headed geese (anser indicus).as one of the dominant waterfowl species of wetland areas in the qinghai-tibet plateau, since 2003, artificial rearing of bar-headed geese (anser indicus) has increased in several provinces of china for the purpose of conservation and economic development. in this study, we systematically characterized the microbial community diversity, compositions and predicted functions of semi-artificially reared bar-headed geese by sampling five different gut locations (the oropharynxs, crops, gizzards, cec ...202031768913
tackling the tibetan plateau in a down suit: insights into thermoregulation by bar-headed geese during migration.birds migrating through extreme environments can experience a range of challenges while meeting the demands of flight, including highly variable ambient temperatures, humidity and oxygen levels. however, there has been limited research into avian thermoregulation during migration in extreme environments. this study aimed to investigate the effect of flight performance and high altitude on body temperature (tb) of free-flying bar-headed geese (anser indicus), a species that completes a high-altit ...201931601684
the highs and lows of bird geese lower their flight metabolic rates to fly in low-oxygen conditions.201931478484
reduced metabolism supports hypoxic flight in the high-flying bar-headed goose (anser indicus).the bar-headed goose is famed for migratory flight at extreme altitude. to better understand the physiology underlying this remarkable behavior, we imprinted and trained geese, collecting the first cardiorespiratory measurements of bar-headed geese flying at simulated altitude in a wind tunnel. metabolic rate during flight increased 16-fold from rest, supported by an increase in the estimated amount of o2 transported per heartbeat and a modest increase in heart rate. the geese appear to have amp ...201931478481
investigating home range, movement pattern, and habitat selection of bar-headed geese during breeding season at qinghai lake, china.the bar-headed goose is the only true goose species or anserinae to migrate solely within the central asian flyway, and thus, it is an ideal species for observing the effects of both land use and climate change throughout the flyway. in this paper, we investigate the home range, movement pattern, and habitat selection of bar-headed geese (anser indicus) during the breeding season at qinghai lake, which is one of their largest breeding areas and a major migration staging area in the flyway. we id ...201830340319
crystal structure analysis of great cormorant (phalacrocorax carbo) hemoglobin to understand its high oxygen affinity characteristics by special structural features.hemoglobin (hb) subunits are composed of the specific functional prosthetic group "heme'' and a protein moiety "globin". bird hbs are functionally similar to mammalian hbs but they are structurally dissimilar with mammalian. the insufficient structural studies on avian hbs limit us to understand their degree of adaptation to such critical environments. the great cormorant (gct) can fly and swim, the dual characteristic of gct leads to study the sturcture of hemoglobin.201829929459
molecular basis of hemoglobin adaptation in the high-flying bar-headed goose.during the adaptive evolution of a particular trait, some selectively fixed mutations may be directly causative and others may be purely compensatory. the relative contribution of these two classes of mutation to adaptive phenotypic evolution depends on the form and prevalence of mutational pleiotropy. to investigate the nature of adaptive substitutions and their pleiotropic effects, we used a protein engineering approach to characterize the molecular basis of hemoglobin (hb) adaptation in the h ...201829608560
respiratory mechanics and morphology of tibetan and andean high-altitude geese with divergent life histories.high-altitude bar-headed geese (anser indicus) and andean geese (chloephaga melanoptera) have been shown to preferentially increase tidal volume over breathing frequency when increasing ventilation during exposure to hypoxia. increasing tidal volume is a more effective breathing strategy but is also thought to be more mechanically and metabolically expensive. we asked whether there might be differences in the mechanics or morphology of the respiratory systems of high-altitude transient bar-heade ...201829180602
divergent respiratory and cardiovascular responses to hypoxia in bar-headed geese and andean birds.many high-altitude vertebrates have evolved increased capacities in their oxygen transport cascade (ventilation, pulmonary diffusion, circulation and tissue diffusion), enhancing oxygen transfer from the atmosphere to mitochondria. however, the extent of interspecies variation in the control processes that dictate hypoxia responses remains largely unknown. we compared the metabolic, cardiovascular and respiratory responses to progressive decreases in inspired oxygen levels of bar-headed geese (a ...201729141880
productivity benefits of warming at regional scale could be offset by detrimental impacts on site level hydrology.climate change affects the distribution and persistence of wildlife. broad scale studies have demonstrated that climate change shifts the geographic ranges and phenology of species. these findings are influential for making high level strategies but not practical enough to guide site specific management. in this study, we explored the environment factors affecting the population of bar-headed goose in the key breeding site of qinghai using generalized additive mixed model (gamm). our results sho ...201729123146
do contrasting patterns of migration movements and disease outbreaks between congeneric waterfowl species reflect differing immunity?long-distance migrations influence the dynamics of hostpathogen interactions and understanding the role of migratory waterfowl in the spread of the highly pathogenic avian influenza viruses (hpaiv) is important. while wild geese have been associated with outbreak events, disease ecology of closely related species has not been studied to the same extent. the swan goose (anser cygnoides) and the bar-headed goose (anser indicus) are congeneric species with distinctly different hpaiv infection recor ...202134000793
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