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Wednesday, 1 October 2014

PubMed Bird Research Highlights September 2014 Week 4


PubMed listing for 'bird' OR 'songbird' excluding references to influenza and flu - September 2014 Week 3



1.Horm Behav. 2014 Sep 22. pii: S0018-506X(14)00197-4. doi: 10.1016/j.yhbeh.2014.09.011. [Epub ahead of print]

Stress, captivity, and reproduction in a wild bird species.

Dickens MJ-1, Bentley GE-2.

Author information:
1- Department of Integrative Biology at University of California at Berkeley. Electronic address: m.dickens@berkeley.edu.
2- Department of Integrative Biology at University of California at Berkeley; Helen Wills Neuroscience Institute, University of California at Berkeley.

Abstract

In seasonal species, glucocorticoid concentrations are often highest during the breeding season. However, the role of increased hypothalamic-pituitary-adrenal (HPA) activity in the regulation of reproduction remains poorly understood. Our study is the first, to our knowledge, to document reproductive consequences of a non-pharmacological hindrance to seasonal HPA fluctuations. Using wild-caught male and female European starlings (Sturnus vulgaris) housed in an outdoor, semi-natural environment, we divided birds into two mixed-sex groups. One group remained in the outdoor aviary, where starlings breed at the appropriate time of year. The other group was transferred into an indoor flight aviary, where we predicted reproductive suppression to occur. We measured changes in corticosterone (CORT) at baseline and stress-induced concentrations prior to group separation and at the experiment's conclusion. After ten days, the birds showed remarkable differences in breeding behavior and HPA activity. Outdoor birds exhibited increases in baseline and stress-induced CORT and progressed into active breeding (pairing, nest building, egg laying, etc.). In contrast, indoor birds displayed no change in baseline or stress-induced CORT and few signs of active breeding. We found significant sex and treatment effects on expression of HPA and hypothalamic pituitary gonadal (HPG) axis elements, suggesting sex-specific regulatory mechanisms. Our data suggest a novel, facilitating role for the HPA axis in the transition between early breeding and active breeding in a wild, seasonal avian species. In addition, understanding how changes in housing condition affect seasonal HPA fluctuations may help alleviate barriers to breeding wild animals in captivity.

Copyright © 2014. Published by Elsevier Inc.

PMID: 25257808 [PubMed - as supplied by publisher]



2.

Mol Phylogenet Evol. 2014 Sep 22. pii: S1055-7903(14)00320-0. doi: 10.1016/j.ympev.2014.09.008. [Epub ahead of print]

Deep global evolutionary radiation in birds: Diversification and trait evolution in the cosmopolitan bird family Rallidae.

Garcia-R JC-1, Gibb GC-2, Trewick SA-2.

Author information:
1- Ecology Group, Institute of Agriculture and Environment, Massey University, Private Bag 11-222, Palmerston North, New Zealand. Electronic address:j.c.garciaramirez@massey.ac.nz.
2- Ecology Group, Institute of Agriculture and Environment, Massey University, Private Bag 11-222, Palmerston North, New Zealand.

Abstract

Sufficient breadth of taxon sampling in major organisms groups is important to identify more realistic biological diversification processes that reveal the degree of historical biogeographic signal and net diversification retained in the current lineage distribution. We examine the mechanisms driving diversity in one of the major avian clades with an exceptional large-scale radiation, the family Rallidae, using the most complete species-level (∼70%) time calibrated hypothesis of evolutionary relationships produced to date. We find that Rallidae exhibit a pattern of diversification involving episodes of range expansion and regional speciation that results in most clades represented in all habitable continents. Our results suggest that several features may have played an important role on the diversification rates in Rallidae. Lineage accumulation is nearly constant and morphology (frontal shield and body size), innovate (flightlessness), habitat (forest) and distribution (insular) traits are possibly associated with increasing diversification rates along with spatial and ecological processes during the Miocene and Pliocene. Diversification and the global retention of lineage diversity have occurred in multiple lineages in Rallidae due to their dispersal ability and exploitation of ecological opportunities.

Copyright © 2014 Elsevier Inc. All rights reserved.

PMID: 25255711 [PubMed - as supplied by publisher]


3.

Biol Reprod. 2014 Sep 24. pii: biolreprod.114.119826. [Epub ahead of print]

Glycosylated Chicken ZP2 Accumulates in the Egg Coat of Immature Oocytes and Remains Localized to the Germinal Disc Region of Mature Eggs.

Nishio S, Kohno Y, Iwata Y, Arai M, Okumura H, Oshima K, Nadano D, Matsuda T.

Abstract

Vertebrate eggs are surrounded by an egg coat, which is a specific extracellular egg matrix consisting of several glycoproteins with a conserved zona pellucida (ZP) domain. Two mammalian egg coat subunits, ZP2 and ZP3, have been suggested to act as sperm receptors. In bird eggs, however, ZP2 has never been identified in the egg coat of mature oocytes and ovulated eggs. Here we report that chicken ZP2 is expressed in immature small follicles and remains as an egg-coat component locally in the germinal disc region of mature eggs. RT-PCR analysis indicated marked expression of the ZP2 and ZP4 genes in the granulosa cells of immature white follicles, whereas the ZP3 and ZPD genes showed marked expression in the cells of maturing yellow follicles. ZP2 was identified in the egg coat isolated from immature follicles as a heavily N-glycosylated glycoprotein of ~200 kDa, which was enzymatically converted to a 70-kDa deglycosylated form. Immunoblotting and immunohistological analyses showed that ZP2 was localized around the germinal disc region of mature follicles. ZP2 was accumulated in the egg coat of immature white follicles at the earlier stages of oocyte development and became a minor component in the egg coat of maturing yellow follicles, except for the germinal disc region. The localization of ZP2 in the germinal disc region of mature eggs, where sperm bind to the egg coat at high density, suggests some role of ZP2 in the preferential binding and penetration of sperm in the germinal disc region of bird eggs.

Copyright 2014 by The Society for the Study of Reproduction.
Free Article
PMID: 25253730 [PubMed - as supplied by publisher]




4.

Nature. 2014 Sep 24. doi: 10.1038/nature13696. [Epub ahead of print]

Individual improvements and selective mortality shape lifelong migratory performance.

Sergio F-1, Tanferna A-1, De Stephanis R-1, Jiménez LL-1, Blas J-1, Tavecchia G-2,Preatoni D-3, Hiraldo F1.

Author information:
1- Department of Conservation Biology, Estación Biológica de Doñana-CSIC, Avenida Americo Vespucio, 41092 Seville, Spain.
2- Population Ecology Group, Institute for Mediterranean Studies (IMEDEA), CSIC-UIB, 07190 Esporles, Spain.
3- Department of Theoretical and Applied Sciences, Insubria University, 21100 Varese, Italy.

Abstract

Billions of organisms, from bacteria to humans, migrate each year and research on their migration biology is expanding rapidly through ever more sophisticated remote sensing technologies. However, little is known about how migratory performance develops through life for any organism. To date, age variation has been almost systematically simplified into a dichotomous comparison between recently born juveniles at their first migration versus adults of unknown age. These comparisons have regularly highlighted better migratory performance by adults compared with juveniles, but it is unknown whether such variation is gradual or abrupt and whether it is driven by improvements within the individual, by selective mortality of poor performers, or both. Here we exploit the opportunity offered by long-term monitoring of individuals through Global Positioning System (GPS) satellite tracking to combine within-individual and cross-sectional data on 364 migration episodes from 92 individuals of a raptorial bird, aged 1-27 years old. We show that the development of migratory behaviour follows a consistent trajectory, more gradual and prolonged than previously appreciated, and that this is promoted by both individual improvements and selective mortality, mainly operating in early life and during the pre-breeding migration. Individuals of different age used different travelling tactics and varied in their ability to exploit tailwinds or to cope with wind drift. All individuals seemed aligned along a race with their contemporary peers, whose outcome was largely determined by the ability to depart early, affecting their subsequent recruitment, reproduction and survival. Understanding how climate change and human action can affect the migration of younger animals may be the key to managing and forecasting the declines of many threatened migrants.

PMID: 25252973 [PubMed - as supplied by publisher]





5.

J Biol Rhythms. 2014 Sep 24. pii: 0748730414549766. [Epub ahead of print]

Annual Life History-Dependent Gene Expression in the Hypothalamus and Liver of a Migratory Songbird: Insights into the Molecular Regulation of Seasonal Metabolism.

Trivedi AK-1, Kumar J-2, Rani S-2, Kumar V-3.

Author information:
1- Department of Zoology, University of Delhi, Delhi, India.
2- Department of Zoology, University of Lucknow, Lucknow, India.
3- Department of Zoology, University of Delhi, Delhi, India drvkumar11@yahoo.comvkumar@zoology.du.ac.in.

Abstract

Birds seasonally switch from one life history state (LHS) to another to maximize their fitness. Accordingly, they exhibit distinct differences in their physiological and behavioral phenotypes between seasons. Possible molecular mechanisms underlying changes through the seasons have scarcely been examined in migratory birds. The present study measured key genes suggested to be involved in the metabolic regulation of 4 photoperiodically induced seasonal LHSs in a long-distance migratory songbird, the blackheaded bunting (Emberiza melanocephala). Buntings were held under short days (8 h light:16 h darkness, 8L:16D), during which they maintained the winter nonmigratory phenotype. Then they were exposed for several weeks to long days (13L:11D). Differences in the activity-rest pattern, body fattening and weight gain, testis size, organ (heart, intestine) weights, and blood glucose and triglyceride levels confirmed that buntings sequentially exhibited spring migration-linked premigratory, migratory, and postmigratory LHSs under long days. The mRNA levels of circadian genes involved in metabolism (Bmal1, Clock, Npas2, Rorα, and Rev-erbα) and of genes that encode for proteins/enzymes involved in the regulation of glucose (Sirt1, FoxO1, Glut1, and Pygl) and lipids (Hmg-CoA; Pparα, Pparγ; Fasn and Acaca) showed LHS-dependent changes in their light-dark expression patterns in the hypothalamus and liver. These initial results on genetic regulation of metabolism in a migratory species extend the idea that the transitions between LHSs in a seasonal species are accomplished by changes at multiple regulatory levels. Thus, these findings promise new insights into the mechanism(s) of adaptation to seasons in higher vertebrates.

© 2014 The Author(s).
PMID: 25252711 [PubMed - as supplied by publisher]




6.

PLoS One. 2014 Sep 24;9(9):e108929. doi: 10.1371/journal.pone.0108929. eCollection 2014.

Hemispheric Asymmetry in New Neurons in Adulthood Is Associated with Vocal Learning and Auditory Memory.

Tsoi SC-1, Aiya UV-2, Wasner KD-3, Phan ML-2, Pytte CL-4, Vicario DS-2.

Author information:
1- Biology Department, The Graduate Center, City University of New York, New York, New York, United States of America.
2- Psychology Department, Rutgers, The State University of New Jersey, Piscataway, New Jersey, United States of America.
3- Psychology Department, Queens College, City University of New York, New York, New York, United States of America.
4- Biology Department, The Graduate Center, City University of New York, New York, New York, United States of America; Psychology Department, Queens College, City University of New York, New York, New York, United States of America.

Abstract

Many brain regions exhibit lateral differences in structure and function, and also incorporate new neurons in adulthood, thought to function in learning and in the formation of new memories. However, the contribution of new neurons to hemispheric differences in processing is unknown. The present study combines cellular, behavioral, and physiological methods to address whether 1) new neuron incorporation differs between the brain hemispheres, and 2) the degree to which hemispheric lateralization of new neurons correlates with behavioral and physiological measures of learning and memory. The songbird provides a model system for assessing the contribution of new neurons to hemispheric specialization because songbird brain areas for vocal processing are functionally lateralized and receive a continuous influx of new neurons in adulthood. In adult male zebra finches, we quantified new neurons in the caudomedial nidopallium (NCM), a forebrain area involved in discrimination and memory for the complex vocalizations of individual conspecifics. We assessed song learning and recorded neural responses to song in NCM. We found significantly more new neurons labeled in left than in right NCM; moreover, the degree of asymmetry in new neuron numbers was correlated with the quality of song learning and strength of neuronal memory for recently heard songs. In birds with experimentally impaired song quality, the hemispheric difference in new neurons was diminished. These results suggest that new neurons may contribute to an allocation of function between the hemispheres that underlies the learning and processing of complex signals.

Free Article
PMID: 25251077 [PubMed - as supplied by publisher]




7.

PLoS One. 2014 Sep 24;9(9):e108741. doi: 10.1371/journal.pone.0108741. eCollection 2014.

When David Beats Goliath: The Advantage of Large Size in Interspecific Aggressive Contests Declines over Evolutionary Time.

Martin PR-1, Ghalambor CK-2.

Author information:
1- Department of Biology, Queen's University, Kingston, Ontario, Canada.
2- Department of Biology and Graduate Degree Program in Ecology, Colorado State University, Fort Collins, Colorado, United States of America.

Abstract

Body size has long been recognized to play a key role in shaping species interactions. For example, while small species thrive in a diversity of environments, they typically lose aggressive contests for resources with larger species. However, numerous examples exist of smaller species dominating larger species during aggressive interactions, suggesting that the evolution of traits can allow species to overcome the competitive disadvantage of small size. If these traits accumulate as lineages diverge, then the advantage of large size in interspecific aggressive interactions should decline with increased evolutionary distance. We tested this hypothesis using data on the outcomes of 23,362 aggressive interactions among 246 bird species pairs involving vultures at carcasses, hummingbirds at nectar sources, and antbirds and woodcreepers at army ant swarms. We found the advantage of large size declined as species became more evolutionarily divergent, and smaller species were more likely to dominate aggressive contests when interacting with more distantly-related species. These results appear to be caused by both the evolution of traits in smaller species that enhanced their abilities in aggressive contests, and the evolution of traits in larger species that were adaptive for other functions, but compromised their abilities to compete aggressively. Specific traits that may provide advantages to small species in aggressive interactions included well-developed leg musculature and talons, enhanced flight acceleration and maneuverability, novel fighting behaviors, and traits associated with aggression, such as testosterone and muscle development. Traits that may have hindered larger species in aggressive interactions included the evolution of morphologies for tree trunk foraging that compromised performance in aggressive contests away from trunks, and the evolution of migration. Overall, our results suggest that fundamental trade-offs, such as those associated with body size, are more likely to break down over evolutionary time, changing the rules that govern species interactions and structure ecological communities.

Free Article
PMID: 25250781 [PubMed - as supplied by publisher]




8.

PLoS One. 2014 Sep 24;9(9):e108244. doi: 10.1371/journal.pone.0108244. eCollection 2014.

The Parasitic Eyeworm Oxyspirura petrowi as a Possible Cause of Decline in the Threatened Lesser Prairie-Chicken (Tympanuchus pallidicinctus).

Dunham NR, Peper ST, Baxter CE, Kendall RJ.

Author information:
The Wildlife Toxicology Laboratory, The Institute of Environmental and Human Health, Texas Tech University, Lubbock, Texas, United States of America.

Abstract

Lesser prairie-chickens (Tympanuchus pallidicinctus) have been declining range wide since the early 1900's despite efforts to establish conservation and improve their habitat. In early 2014, the lesser prairie-chicken was listed as a threatened species under the U.S Endangered Species Act and the need to find out why they are declining is more important than ever. Nine hunter shot lesser prairie-chickens were donated and sampled for the presence or absence of the eyeworm Oxyspirura petrowi, a known parasite that can cause damage to the eye of its host, and common environmental contaminants. Eyeworm infection was found in 7 of 9 birds (78% infection rate) with an infection range between 0-16 O. petrowi per bird. Breast, liver, and fat tissue samples from the lesser prairie-chickens were analyzed for the frequency of 20 organochlorine pesticides. Femurs and livers were also tested on these birds for metal contaminants. Pesticides were found in several samples above the detection limits but were still in the low ng/g range. Notable was the ubiquitous presence of endrin aldehyde across all tissues. One femur showed 5.66 µg/g of lead (Pb) but this is still relatively low. No liver samples had elevated mercury (Hg) above detection limits. The presence of these organochlorines is consistent with the historic use of pesticides in this region. With pesticide and metals found in such low levels and parasitic nematode infections at rather high levels, it is recommended that these parasites be further evaluated as a contributing factor to the decline of the lesser prairie-chicken.

Free Article
PMID: 25250776 [PubMed - as supplied by publisher]




9.

Br Poult Sci. 2014 Sep 23. [Epub ahead of print]

Genetic analysis of production and feed efficiency traits in an Orlopp turkey line (Meleagris gallopavo).

Willems OW-1, Buddiger NJ, Wood BJ.

Author information:
1- Centre for the Genetic Improvement of Livestock, Department of Animal and Poultry Science , University of Guelph , Guelph , ON , Canada.

Abstract


1. Evaluating production and feed efficiency traits in each line of turkeys at the pure line or pedigree level is an important step in assessing the direction of breeding goals and future potential of the line in a long-term genetic improvement. 2. In dam line turkeys the focus of a breeding programme is on mixture of body weight, feed efficiency traits, such as feed conversion ratio (FCR), egg production and fertility traits. Feed efficiency traits for each individual bird that underwent feed efficiency testing were measured over a 4-week period, from 16-20 weeks of age, during which they had ad libitum access to feed and water. 3. Moderate heritabilities were found for feed intake and body weight gain (0.25 to 0.31). Average FCR was 3.14, with heritability of 0.10. Body weight, breast conformation score and egg production traits showed moderate heritabilities (0.22 to 0.52), while both fertility and hatch of fertile were low (0.04 and 0.09, respectively). 4. Genetic correlations between breast confirmation score, 10 and 18-week body weights were moderate, 0.50 and 0.45, respectively. Average egg weight also showed moderate genetic correlations with 10 and 18-week body weights (0.59 and 0.42).

PMID: 25248125 [PubMed - as supplied by publisher]




10.J Exp Biol. 2014 Sep 15;217(Pt 18):3326-32. doi: 10.1242/jeb.103291.

Nesting behaviour influences species-specific gas exchange across avian eggshells.

Portugal SJ-1, Maurer G-2, Thomas GH-3, Hauber ME-4, Grim T-5, Cassey P-2.

Author information:
1- Structure and Motion Laboratory, The Royal Veterinary College, University of London, North Mymms, Hatfield, Herts AL9 7TA, UK SPortugal@rvc.ac.uk.
2- School of Earth and Environmental Sciences, University of Adelaide, SA 5005 Australia.
3- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.
4- Department of Psychology, Hunter College and the Graduate Center of the City University of New York, 695 Park Avenue, New York, NY 10065, USA.
5- Department of Zoology and Laboratory of Ornithology, Palacký University, Olomouc, CZ-771 46 Czech Republic.

Abstract

Carefully controlled gas exchange across the eggshell is essential for the development of the avian embryo. Water vapour conductance (GH2O) across the shell, typically measured as mass loss during incubation, has been demonstrated to optimally ensure the healthy development of the embryo while avoiding desiccation. Accordingly, eggs exposed to sub-optimal gas exchange have reduced hatching success. We tested the association between eggshell GH2O and putative life-history correlates of adult birds, ecological nest parameters and physical characteristics of the egg itself to investigate how variation in GH2O has evolved to maintain optimal water loss across a diverse set of nest environments. We measured gas exchange through eggshell fragments in 151 British breeding bird species and fitted phylogenetically controlled, general linear models to test the relationship between GH2O and potential predictor parameters of each species. Of our 17 life-history traits, only two were retained in the final model: wet-incubating parent and nest type. Eggs of species where the parent habitually returned to the nest with wet plumage had significantly higher GH2O than those of parents that returned to the nest with dry plumage. Eggs of species nesting in ground burrows, cliffs and arboreal cups had significantly higher GH2O than those of species nesting on the ground in open nests or cups, in tree cavities and in shallow arboreal nests. Phylogenetic signal (measured as Pagel's λ) was intermediate in magnitude, suggesting that differences observed in the GH2O are dependent upon a combination of shared ancestry and species-specific life history and ecological traits. Although these data are correlational by nature, they are consistent with the hypothesis that parents constrained to return to the nest with wet plumage will increase the humidity of the nest environment, and the eggs of these species have evolved a higher GH2O to overcome this constraint and still achieve optimal water loss during incubation. We also suggest that eggs laid in cup nests and burrows may require a higher GH2O to overcome the increased humidity as a result from the confined nest microclimate lacking air movements through the nest. Taken together, these comparative data imply that species-specific levels of gas exchange across avian eggshells are variable and evolve in response to ecological and physical variation resulting from parental and nesting behaviours.

© 2014. Published by The Company of Biologists Ltd.
PMID: 25232199 [PubMed - in process]





11.

Parasitol Res. 2014 Sep 18. [Epub ahead of print]

Host specificity of a bird-specialised endophilic ectoparasite, the tree-hole tick Ixodes arboricola.

Van Oosten AR-1, Heylen DJ, Matthysen E.

Author information:
1- University of Antwerp, Groenenborgerlaan 171, 2020, Antwerp, Belgium,raoul.vanoosten@uantwerpen.be.

Abstract

Host specialisation in parasites can be due to either limited exposure or limited adaptation to different host types. When the first barrier is lifted experimentally, the degree of adaptive specialisation can be studied. The tree-hole tick Ixodes arboricola is an endophilic parasite with a narrow host range, found in nest boxes used mainly by great and blue tits (Parus major, Cyanistes caeruleus) and to a lesser extent by pied flycatchers (Ficedula hypoleuca) and nuthatches (Sitta europaea). In the current study, we exposed two nestlings per nestbox of pied flycatchers (N = 14), blue tits (N = 18), great tits (N = 14), and nuthatches (N = 16) to ten I. arboricola nymphs each. We found no differences in attachment success 2 days after infestation (56 ± 4 % across species) nor were there any differences in tick engorgement weight (1.95 ± 0.03 mg across species), and moulting success was >90 % for ticks from all bird species. Hence, our data suggest that all bird species investigated here are suitable host species. This may enhance the ticks' chances for persistence in cavities and dispersal among cavities inhabited by multiple host species, and supports the hypothesis that host use by ticks is limited by host ecology rather than by host specialisation.

PMID: 25231076 [PubMed - as supplied by publisher]





12.

Ecology. 2014 Aug;95(8):2334-45.

Repeated patterns of trait divergence between closely related dominant and subordinate bird species.

Freshwater C, Ghalambor CK, Martin PR.

Abstract

Ecologically similar species often compete aggressively for shared resources. These interactions are frequently asymmetric, with one species behaviorally dominant to another and excluding it from preferred resources. Despite the potential importance of this type of interference competition as a source of selection, we know little about patterns of trait divergence between dominant and subordinate species. We compiled published data on phylogenetically independent, closely related species of North American birds where one species was consistently dominant in aggressive interactions with a congeneric species. We then compared the body size, breeding phenology, life history, ecological breadth, and biogeography of these species. After accounting for body size and phylogeny, we found repeated patterns of trait divergence between subordinate and dominant species within genera. Subordinate species that migrated seasonally arrived 4-7 days later than dominants on their sympatric breeding grounds, and both resident and migratory subordinates initiated breeding 7-8 days later than their dominant, sympatric congeners. Subordinate species had a 5.2% higher annual adult mortality rate and laid eggs that were 0.02 g heavier for their body mass. Dominant and subordinate species used a similar number of different foods, foraging behaviors, nest sites, and habitats, but subordinates were more specialized in their foraging behaviors compared with closely related dominant species. The breeding and wintering ranges of subordinate species were 571 km farther apart than the ranges of dominant species, suggesting that subordinate species migrate greater distances. Range sizes and latitudinal distributions did not consistently differ, although subordinate species tended to breed farther north or winter farther south. These results are consistent with dominant species directly influencing the ecological strategies of subordinate species (via plastic or genetically based changes), either by restricting their access to resources or simply through aggression. Alternatively, these ecological traits may covary with patterns of behavioral dominance, with no direct consequences of interactions. Regardless of the mechanism, recognizing that the relative position of a species within a dominance hierarchy is correlated with a suite of other ecological and fitness related traits has far-reaching implications for the mechanisms underlying species distributions and the structure of biological assemblages.

PMID: 25230483 [PubMed - in process]


13.

PLoS One. 2014 Sep 17;9(9):e107357. doi: 10.1371/journal.pone.0107357. eCollection 2014.

Does Rearing Laying Hens in Aviaries Adversely Affect Long-Term Welfare following Transfer to Furnished Cages?

Tahamtani FM-1, Hansen TB-2, Orritt R-3, Nicol C-4, Moe RO-1, Janczak AM-1.

Author information:
1- Animal Welfare Research Group, Department of Production Animal Clinical Science, NMBU, Oslo, Norway.
2- Animalia, Norwegian Meat and Poultry Research Centre, Oslo, Norway.
3- Animal Welfare Research Group, Department of Production Animal Clinical Science, NMBU, Oslo, Norway; School of Psychology, University of Lincoln, Lincoln, United Kingdom.
4- Division of Animal Health and Husbandry, University of Bristol, Bristol, United Kingdom.

Abstract

This study tests the hypothesis that hens that are reared in aviaries but produce in furnished cages experience poorer welfare in production than hens reared in caged systems. This hypothesis is based on the suggestion that the spatial restriction associated with the transfer from aviaries to cages results in frustration or stress for the aviary reared birds. To assess the difference in welfare between aviary and cage reared hens in production, non-beak trimmed white leghorn birds from both rearing backgrounds were filmed at a commercial farm that used furnished cage housing. The videos were taken at 19 and 21 weeks of age, following the birds' transition to the production environment at 16 weeks. Videos were analysed in terms of the performance of aversion-related behaviour in undisturbed birds, comfort behaviour in undisturbed birds, and alert behaviour directed to a novel object in the home cage. A decrease in the performance of the former behaviour and increase in the performance of the latter two behaviours indicates improved welfare. The results showed that aviary reared birds performed more alert behaviour near to the object than did cage reared birds at 19 but not at 21 weeks of age (P = 0.03). Blood glucose concentrations did not differ between the treatments (P>0.10). There was a significant difference in mortality between treatments (P = 0.000), with more death in aviary reared birds (5.52%) compared to cage birds (2.48%). The higher mortality of aviary-reared birds indicates a negative effect of aviary rearing on bird welfare, whereas the higher duration of alert behavior suggests a positive effect of aviary rearing.

Free Article
PMID: 25229879 [PubMed - in process]




14.

J Vet Pharmacol Ther. 2014 Sep 17. doi: 10.1111/jvp.12159. [Epub ahead of print]

Partial cloning of CYP2C23a genes and hepatic protein expression in eight representative avian species.

Watanabe KP-1, Kawai YK, Nakayama SM, Ikenaka Y, Mizukawa H, Takaesu N, Ito M, Ikushiro SI, Sakaki T, Ishizuka M.

Author information:
1- Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan.

Abstract

Large interspecies differences in avian xenobiotic metabolism have been revealed by microsome-based studies, but specific enzyme isoforms in different bird species have not yet been compared. We have previously shown that CYP2C23 genes are the most induced CYP isoforms in chicken liver. In this study, we collected partial CYP2C23a gene sequences from eight avian species (ostrich, blue-eared pheasant, snowy owl, great-horned owl, Chilean flamingo, peregrin falcon, Humboldt penguin, and black-crowned night heron) selected to cover the whole avian lineage: Paleognathae, Galloanserae, and Neoaves. Genetic analysis showed that CYP2C23 genes of Galloanserae species (chicken and blue-eared pheasant) had unique characteristics. We found some duplicated genes (CYP2C23a and CYP2C23b) and two missing amino acid residues in Galloanserae compared to the other two lineages. The genes have lower homology than in other avian lineages, which suggests Galloanserae-specific rapid evolutionary changes. These genetic features suggested that the Galloanserae are not the most representative avian species, considering that the Neoaves comprise more than 95% of birds. Moreover, we succeeded in synthesizing an antipeptide polyclonal antibody against the region of CYP2C23 protein conserved in avians. However, comparative quantitation of CYP2C23 proteins in livers from six species showed that expression levels of these proteins differed no more than fourfold. Further study is needed to clarify the function of avian CYP2C23 proteins.

© 2014 John Wiley & Sons Ltd.
PMID: 25229839 [PubMed - as supplied by publisher]


15.

Naturwissenschaften. 2014 Sep 17. [Epub ahead of print]

Do feather-degrading bacteria actually degrade feather colour? No significant effects of plumage microbiome modifications on feather colouration in wild great tits.

Jacob S-1, Colmas L, Parthuisot N, Heeb P.

Author information:
1- Laboratoire Évolution et Diversité Biologique (EDB), UMR 5174 Centre National de la Recherche Scientifique (CNRS), Ecole Nationale de Formation Agronomique (ENFA)-Université Paul Sabatier, 118 Route de Narbonne, 31062, Toulouse, France, jacobstaffan@gmail.com.

Abstract

Parasites are known to exert selective pressures on host life history traits since the energy and nutrients needed to mount an immune response are no longer available to invest in other functions. Bird feathers harbour numerous microorganisms, some of which are able to degrade feather keratin (keratinolytic microorganisms) and affect feather integrity and colouration in vitro. Although named "feather-degrading" microorganisms, experimental evidence for their effects on feathers of free-living birds is still lacking. Here, we tested whether (i) keratinolytic microorganisms can degrade feathers in vivo and thus modify the colour of feathers during the nesting period and (ii) whether feather microorganisms have a long-term effect on the investment in colouration of newly moulted feathers. We designed treatments to either favour or inhibit bacterial growth, thus experimentally modifying plumage bacterial communities, in a wild breeding population of great tits (Parus major). Our analyses revealed no significant effects of the treatments on feather colours. Moreover, we found that differences in bacterial exposure during nesting did not significantly affect the colouration of newly moulted feathers. Our results suggest that significant feather degradation obtained during in vitro studies could have led to an overestimation of the potential of keratinolytic microorganisms to shape feather colouration in free-living birds.

PMID: 25228345 [PubMed - as supplied by publisher]




16.

PLoS One. 2014 Sep 16;9(9):e107883. doi: 10.1371/journal.pone.0107883. eCollection 2014.

American exceptionalism: population trends and flight initiation distances in birds from three continents.

Møller AP-1, Samia DS-2, Weston MA-3, Guay PJ-4, Blumstein DT-5.

Author information:
1- Laboratoire d'Ecologie, Systématique et Evolution, Centre National de la Recherche Scientifique Unité Mixte de Recherche 8079, Université Paris-Sud, Orsay, France.
2- Ecology and Evolution, Laboratory of Theoretical Ecology and Synthesis, Federal University of Goiás, Goiânia, Brazil.
3- Centre for Integrative Ecology, School of Life and Environmental Sciences, Faculty of Science, Engineering and the Built Environment, Deakin University, Melbourne, Victoria, Australia.
4- College of Engineering and Science, and Institute for Sustainability and Innovation, Victoria University, Footscray Park Campus, Melbourne, Victoria, Australia.
5- Department of Ecology & Evolutionary Biology, University of California Los Angeles, Los Angeles, California, United States of America.

Abstract

BACKGROUND:
All organisms may be affected by humans' increasing impact on Earth, but there are many potential drivers of population trends and the relative importance of each remains largely unknown. The causes of spatial patterns in population trends and their relationship with animal responses to human proximity are even less known.

METHODOLOGY/PRINCIPAL FINDING:
We investigated the relationship between population trends of 193 species of bird in North America, Australia and Europe and flight initiation distance (FID); the distance at which birds take flight when approached by a human. While there is an expected negative relationship between population trend and FID in Australia and Europe, we found the inverse relationship for North American birds; thus FID cannot be used as a universal predictor of vulnerability of birds. However, the analysis of the joint explanatory ability of multiple drivers (farmland breeding habitat, pole-most breeding latitude, migratory habit, FID) effects on population status replicated previously reported strong effects of farmland breeding habitat (an effect apparently driven mostly by European birds), as well as strong effects of FID, body size, migratory habit and continent. Farmland birds are generally declining.

CONCLUSIONS/SIGNIFICANCE:
Flight initiation distance is related to population trends in a way that differs among continents opening new research possibilities concerning the causes of geographic differences in patterns of anti-predator behavior.

Free Article
PMID: 25226165 [PubMed - in process]




17.

J Comp Neurol. 2014 Sep 16. doi: 10.1002/cne.23676. [Epub ahead of print]

The Visual System of a Palaeognathous Bird: Visual Field, Retinal Topography and Retino-Central Connections in the Chilean Tinamou (Nothoprocta perdicaria).

Krabichler Q-1, Vega-Zuniga T, Morales C, Luksch H, Marín GJ.

Author information:
1- Lehrstuhl für Zoologie, Technische Universität München, Freising-Weihenstephan, Germany.

Abstract

Most systematic studies of the avian visual system have focused on Neognathous species, leaving virtually unexplored the Palaeognathae, which comprise the flightless ratites and the South American Tinamous. We investigated the visual field, the retinal topography, and the pattern of the retinal and centrifugal projections of the Chilean Tinamou, a small Palaeognath of the family Tinamidae. The Tinamou has a panoramic visual field with a small frontal binocular overlap of 20°. The retina possesses three distinct topographical specializations: a horizontal visual streak, a dorsotemporal area and an area centralis with a shallow fovea. The maximum ganglion cell density is 61,900 per mm², comparable to Falconiformes. This would provide a maximal visual acuity of 14.0 cycles/degree, in spite of relatively small eyes. The central retinal projections generally conform to the characteristic arrangement observed in Neognathae, with well-differentiated contralateral targets and very few ipsilateral fibers. The centrifugal visual system is composed of a considerable number of multipolar centrifugal neurons, resembling the "ectopic" neurons described in Neognathae. They form a diffuse nuclear structure, which may correspond to the basal condition shared with other sauropsids. A notable feature is the presence of terminals in deep tectal layers 11-13. These fibers may represent either a novel retino-tectal pathway or collateral branches from centrifugal neurons projecting to the retina. Both types of connections have been described in chicken embryos. Our results widen the basis for comparative studies of the vertebrate visual system, stressing the conserved character of the visual projections' pattern within the avian clade. J. Comp. Neurol., 2014. © 2014 Wiley Periodicals, Inc.

Copyright © 2014 Wiley Periodicals, Inc., A Wiley Company.
PMID: 25224833 [PubMed - as supplied by publisher]




18.

Mol Ecol Resour. 2014 Sep 15. doi: 10.1111/1755-0998.12330. [Epub ahead of print]

A comparison of SNP and microsatellite markers for analysis of parentage and kinship in a cooperatively breeding bird.

Weinman LR-1, Solomon JW, Rubenstein DR.

Author information:
1- Columbia University, Department of Ecology, Evolution and Environmental Biology, 1200 Amsterdam Avenue, New York, NY, 10027, USA.

Abstract

The development of genetic markers has revolutionized molecular studies within and among populations. Although poly-allelic microsatellites are the most commonly used genetic marker for within-population studies of free-living animals, bi-allelic single nucleotide polymorphisms, or SNPs, have also emerged as a viable option for use in non-model systems. We describe a robust method of SNP discovery from the transcriptome of a non-model organism that resulted in more than 99% of the markers working successfully during genotyping. We then compare the use of 102 novel SNPs with 15 previously-developed microsatellites for studies of parentage and kinship in cooperatively breeding superb starlings (Lamprotornis superbus) that live in highly kin-structured groups. For 95% of the offspring surveyed, SNPs and microsatellites identified the same genetic father, but only when behavioral information about the likely parents at a nest was included to aid in assignment. Moreover, when such behavioral information was available, the number of SNPs necessary for successful parentage assignment was reduced by half. However, in a few cases where candidate fathers were highly related, SNPs did a better job at assigning fathers than microsatellites. Despite high variation between individual pairwise relatedness values, microsatellites and SNPs performed equally well in kinship analyses. This study is the first to compare SNPs and microsatellites for analyses of parentage and relatedness in a species that lives in groups with a complex social and kin structure. It should also prove informative for those interested in developing SNP loci from transcriptome data when published genomes are unavailable. This article is protected by copyright. All rights reserved.

This article is protected by copyright. All rights reserved.
PMID: 25224810 [PubMed - as supplied by publisher]



19.

PLoS One. 2014 Sep 15;9(9):e107491. doi: 10.1371/journal.pone.0107491. eCollection 2014.

A comprehensive analysis of small-passerine fatalities from collision with turbines at wind energy facilities.

Erickson WP-1, Wolfe MM-1, Bay KJ-1, Johnson DH-2, Gehring JL-3.

Author information:
1- Western EcoSystems Technology, Inc., Cheyenne, WY, United States of America.
2- U. S. Geological Survey, Northern Prairie Wildlife Research Center, Saint Paul, MN, United States of America.
3- Federal Communications Commission, Washington, DC, United States of America.


Abstract

Small passerines, sometimes referred to as perching birds or songbirds, are the most abundant bird group in the United States (US) and Canada, and the most common among bird fatalities caused by collision with turbines at wind energy facilities. We used data compiled from 116 studies conducted in the US and Canada to estimate the annual rate of small-bird fatalities. It was necessary for us to calculate estimates of small-bird fatality rates from reported all-bird rates for 30% of studies. The remaining 70% of studies provided data on small-bird fatalities. We then adjusted estimates to account for detection bias and loss of carcasses from scavenging. These studies represented about 15% of current operating capacity (megawatts [MW]) for all wind energy facilities in the US and Canada and provided information on 4,975 bird fatalities, of which we estimated 62.5% were small passerines comprising 156 species. For all wind energy facilities currently in operation, we estimated that about 134,000 to 230,000 small-passerine fatalities from collision with wind turbines occur annually, or 2.10 to 3.35 small birds/MW of installed capacity. When adjusted for species composition, this indicates that about 368,000 fatalities for all bird species are caused annually by collisions with wind turbines. Other human-related sources of bird deaths, (e.g., communication towers, buildings [including windows]), and domestic cats) have been estimated to kill millions to billions of birds each year. Compared to continent-wide population estimates, the cumulative mortality rate per year by species was highest for black-throated blue warbler and tree swallow; 0.043% of the entire population of each species was estimated to annually suffer mortality from collisions with turbines. For the eighteen species with the next highest values, this estimate ranged from 0.008% to 0.038%, much lower than rates attributed to collisions with communication towers (1.2% to 9.0% for top twenty species).

Free Article

PMID: 25222738 [PubMed - in process]

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