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Friday, 8 January 2016

What's new for 'birdRS' in PubMed: January 2016, Week 1

birdRS - Latest News

This message contains My NCBI what's new results from the National Center for Biotechnology Information (NCBI) at the U.S. National Library of Medicine (NLM).

PubMed Results

1. Ecotoxicology. 2015 Dec 30. [Epub ahead of print] 

Barn owl feathers as biomonitors of mercury: sources of variation in sampling procedures. 
Roque I(1), Lourenço R(2), Marques A(2), Coelho JP(3), Coelho C(3), Pereira E(3), Rabaça JE(2,)(4), Roulin A(5). Author information: (1)LabOr - Laboratório de Ornitologia, ICAAM - Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Universidade de Évora, Núcleo da Mitra, Ap. 94, 7002-554, Évora, Portugal. (2)LabOr - Laboratório de Ornitologia, ICAAM - Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Universidade de Évora, Núcleo da Mitra, Ap. 94, 7002-554, Évora, Portugal. (3)CESAM (Centre for Environmental and Marine Studies), Department of Chemistry, University of Aveiro, 3810-193, Aveiro, Portugal. (4)Department of Biology, University of Évora, Ap. 94, 7002-554, Évora, Portugal. (5)Department of Ecology and Evolution, University of Lausanne, Building Biophore, 1015, Lausanne, Switzerland. 

Given their central role in mercury (Hg) excretion and suitability as reservoirs, bird feathers are useful Hg biomonitors. Nevertheless, the interpretation of Hg concentrations is still questioned as a result of a poor knowledge of feather physiology and mechanisms affecting Hg deposition. Given the constraints of feather availability to ecotoxicological studies, we tested the effect of intra-individual differences in Hg concentrations according to feather type (body vs. flight feathers), position in the wing and size (mass and length) in order to understand how these factors could affect Hg estimates. We measured Hg concentration of 154 feathers from 28 un-moulted barn owls (Tyto alba), collected dead on roadsides. Median Hg concentration was 0.45 (0.076-4.5) mg kg(-1) in body feathers, 0.44 (0.040-4.9) mg kg(-1) in primary and 0.60 (0.042-4.7) mg kg(-1) in secondary feathers, and we found a poor effect of feather type on intra-individual Hg levels. We also found a negative effect of wing feather mass on Hg concentration but not of feather length and of its position in the wing. We hypothesize that differences in feather growth rate may be the main driver of between-feather differences in Hg concentrations, which can have implications in the interpretation of Hg concentrations in feathers. Finally, we recommend that, whenever possible, several feathers from the same individual should be analysed. The five innermost primaries have lowest mean deviations to both between-feather and intra-individual mean Hg concentration and thus should be selected under restrictive sampling scenarios. PMID: 26718850 [PubMed - as supplied by publisher] 

2. Gen Comp Endocrinol. 2015 Dec 21. pii: S0016-6480(15)30053-8. doi: 10.1016/j.ygcen.2015.12.020. [Epub ahead of print] 

Hypothalamic-pituitary-adrenal axis activity is not elevated in a songbird (Junco hyemalis) preparing for migration. 
Bauer CM(1), Needham KB(2), Le CN(2), Stewart EC(2), Graham JL(2), Ketterson ED(3), Greives TJ(2). Author information: (1)Department of Biological Sciences, North Dakota State University, Fargo, ND, USA. Electronic address: (2)Department of Biological Sciences, North Dakota State University, Fargo, ND, USA. (3)Department of Biology, Indiana University, Bloomington, IN, USA. 

During spring, increasing daylengths stimulate gonadal development in migratory birds. However, late-stage reproductive development is typically postponed until migration has been completed. The hypothalamic-pituitary-adrenal (HPA) axis regulates the secretion of glucocorticoids, which have been associated with pre-migratory hyperphagia and fattening. The HPA-axis is also known to suppress the hypothalamic-pituitary-gonadal (HPG) axis, suggesting the possibility that final transition into the breeding life history stage may be slowed by glucocorticoids. We hypothesized that greater HPA-axis activity in individuals preparing for migration may foster preparation for migration while simultaneously acting as a "brake" on the development of the HPG-axis. To test this hypothesis, we sampled baseline corticosterone (CORT), stress-induced CORT, and negative feedback efficacy of Dark-eyed Juncos (Junco hyemalis) in an overwintering population that included both migratory (J.h. hyemalis) and resident (J.h. carolinensis) individuals. We predicted that compared to residents, migrants would have higher baseline CORT, higher stress-induced CORT, and weaker negative feedback. Juncos were sampled in western Virginia in early March, which was about 2-4 wk before migratory departure for migrants and 4-5 wk before first clutch initiation for residents. Contrary to our predictions, we found that migrants had lower baseline and stress-induced CORT and similar negative feedback efficacy compared with residents, which suggests that delayed breeding in migrants is influenced by other physiological mechanisms. Our findings also suggest that baseline CORT is not elevated during pre-migratory fattening, as migrants had lower baseline CORT and were fatter than residents. Copyright © 2015. Published by Elsevier Inc. PMID: 26718082 [PubMed - as supplied by publisher] 

3. J Anim Ecol. 2015 Dec 31. doi: 10.1111/1365-2656.12486. [Epub ahead of print] 

Inter-annual variation and long-term trends in proportions of resident individuals in partially migratory birds. 
Meller K(1), Vähätalo AV(2), Hokkanen T(3), Rintala J(4), Piha M(1), Lehikoinen A(1). Author information: (1)The Helsinki Lab of Ornithology, The Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland. (2)Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland. (3)Natural Resources Institute Finland, P.O. Box 18, FI-01301, Vantaa, Finland. (4)Natural Resources Institute Finland, P.O. Box 2, FI-00791, Helsinki, Finland. 

1.Partial migration - a part of a population migrates and another part stays resident year-round on the breeding site - is probably the most common type of migration in the animal kingdom, yet it has only lately garnered more attention. Theoretical studies indicate that in partially migratory populations the proportion of resident individuals (PoR) should increase in high latitudes in response to the warming climate, but empirical evidence exists for few species. 2.We provide the first comprehensive overview of the environmental factors affecting PoR and the long-term trends in PoR by studying 27 common partially migratory bird species in Finland. 3.The annual PoR values were calculated by dividing the winter bird abundances by the preceding breeding abundances. First, we analysed whether early-winter temperature, winter temperature year before or the abundance of tree seeds just before overwintering, explain the inter-annual variation in PoR. Second, we analysed the trends in PoR between 1987 and 2011. 4.Early-winter temperature explained the inter-annual variation in PoR in the waterbirds (waterfowl and gulls), most likely because the temperature affects the ice conditions and thereby the feeding opportunities for the waterbirds. In terrestrial species, the abundance of seeds was the best explanatory variable. Previous winter's temperature did not explain PoR in any species, thus we conclude that variation in food availability caused the inter-annual variation in PoR. During the study period PoR increased in waterbirds but did not change in terrestrial birds. 5.Partially migratory species living in physically contrasting habitats can differ in their annual and long-term population-level behavioural responses to warming climate, possibly because warm winter temperatures reduce ice cover and improve the feeding possibilities of waterbirds but do not directly regulate the food availability for terrestrial birds. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved. PMID: 26718017 [PubMed - as supplied by publisher] 

4. J Anim Ecol. 2015 Dec 30. doi: 10.1111/1365-2656.12481. [Epub ahead of print] 

Integrated population modelling reveals a perceived source to be a cryptic sink. 
Weegman MD(1,)(2), Bearhop S(1), Fox AD(3), Hilton GM(2), Walsh AJ(4), McDonald JL(1), Hodgson DJ(1). Author information: (1)Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Cornwall Campus, TR10 9EZ, United Kingdom. (2)Wildfowl & Wetlands Trust, Slimbridge, Gloucester, GL2 7BT, United Kingdom. (3)Department of Bioscience, Aarhus University, Kalø, Grenåvej 14, DK-8410, Rønde, Denmark. (4)National Parks and Wildlife Service, Wexford Wildfowl Reserve, North Slob, Wexford, Ireland. 

1.Demographic links among fragmented populations are commonly studied as source-sink dynamics, whereby source populations exhibit net recruitment and net emigration, while sinks suffer net mortality but enjoy net immigration. It is commonly assumed that large, persistent aggregations of individuals must be sources, but this ignores the possibility that they are sinks instead, buoyed demographically by immigration. 2.We tested this assumption using Bayesian integrated population modelling of Greenland white-fronted geese (Anser albifrons flavirostris) at their largest wintering site (Wexford, Ireland), combining capture-mark-recapture, census and recruitment data collected from 1982 to 2010. Management for this subspecies occurs largely on wintering areas; thus, study of source-sink dynamics of discrete regular wintering units provides unprecedented insights into population regulation and enables identification of likely processes influencing population dynamics at Wexford and among 70 other Greenland white-fronted goose wintering subpopulations. 3.Using results from integrated population modelling, we parameterized an age-structured population projection matrix to determine the contribution of movement rates (emigration and immigration), recruitment and mortality to the dynamics of the Wexford subpopulation. 4.Survival estimates for juvenile and adult birds at Wexford, and adult birds elsewhere fluctuated over the 29-year study period, but were not identifiably different. However, per capita recruitment rates at Wexford in later years (post-1995) were identifiably lower than in earlier years (pre-1995). The observed persistence of the Wexford subpopulation was only possible with high rates of immigration, which exceeded emigration in each year. Thus, despite its apparent stability, Wexford has functioned as a sink over the entire study period. 5.These results demonstrate that even large subpopulations can potentially be sinks, and that movement dynamics (e.g. immigration) among winters can dramatically obscure key processes driving subpopulation size. Further, novel population models which integrate capture-mark-recapture, census and recruitment data are essential to correctly ascribing source-sink status and accurately informing development of site-safeguard networks. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved. PMID: 26717445 [PubMed - as supplied by publisher] 

5. PLoS One. 2015 Dec 30;10(12):e0145909. doi: 10.1371/journal.pone.0145909. 

Non-Invasive Measurement of Adrenocortical Activity in Blue-Fronted Parrots (Amazona aestiva, Linnaeus, 1758). 
Ferreira JC(1), Fujihara CJ(1), Fruhvald E(1), Trevisol E(1), Destro FC(1), Teixeira CR(2), Pantoja JC(3), Schmidt EM(4), Palme R(5). Author information: (1)Department of Animal Reproduction and Veterinary Radiology, School of Veterinary Medicine and Animal Science, Unesp - Univ Estadual Paulista, Rubião Junior s/n, 18.618-970, Botucatu, Brazil. (2)Department of Veterinary Surgery, School of Veterinary Medicine and Animal Science, Unesp - Univ Estadual Paulista, Rubião Junior s/n, 18.618-970, Botucatu, Brazil. (3)Department of Veterinary Hygiene and Public Health, School of Veterinary Medicine and Animal Science, UNESP - Univ Estadual Paulista, Rubião Junior s/n, 18.618-970, Botucatu, SP, Brazil. (4)Department of Veterinary Clinics, School of Veterinary Medicine and Animal Science, Unesp - Univ Estadual Paulista, Rubião Junior s/n, 18.618-970, Botucatu, Brazil. (5)Department of Biomedical Sciences, Unit of Physiology, Pathophysiology and Experimental Endocrinology, University of Veterinary Medicine, Veterinärplatz 1, 2210, Vienna, Austria. 

Parrots kept in zoos and private households often develop psychological and behavioural disorders. Despite knowing that such disorders have a multifactorial aetiology and that chronic stress is involved, little is known about their development mainly due to a poor understanding of the parrots' physiology and the lack of validated methods to measure stress in these species. In birds, blood corticosterone concentrations provide information about adrenocortical activity. However, blood sampling techniques are difficult, highly invasive and inappropriate to investigate stressful situations and welfare conditions. Thus, a non-invasive method to measure steroid hormones is critically needed. Aiming to perform a physiological validation of a cortisone enzyme immunoassay (EIA) to measure glucocorticoid metabolites (GCM) in droppings of 24 Blue-fronted parrots (Amazona aestiva), two experiments were designed. During the experiments all droppings were collected at 3-h intervals. Initially, birds were sampled for 24 h (experiment 1) and one week later assigned to four different treatments (experiment 2): Control (undisturbed), Saline (0.2 mL of 0.9% NaCl IM), Dexamethasone (1 mg/kg IM) and Adrenocorticotropic hormone (ACTH; 25 IU IM). Treatments (always one week apart) were applied to all animals in a cross-over study design. A daily rhythm pattern in GCM excretion was detected but there were no sex differences (first experiment). Saline and dexamethasone treatments had no effect on GCM (not different from control concentrations). Following ACTH injection, GCM concentration increased about 13.1-fold (median) at the peak (after 3-9 h), and then dropped to pre-treatment concentrations. By a successful physiological validation, we demonstrated the suitability of the cortisone EIA to non-invasively monitor increased adrenocortical activity, and thus, stress in the Blue-fronted parrot. This method opens up new perspectives for investigating the connection between behavioural disorders and stress in this bird species, and could also help in their captive management. PMID: 26717147 [PubMed - as supplied by publisher] 

6. R Soc Open Sci. 2015 Nov 25;2(11):150497. doi: 10.1098/rsos.150497. eCollection 2015. 

Parental influence on begging call structure in zebra finches (Taeniopygia guttata): evidence of early vocal plasticity. 
Villain AS(1), Boucaud IC(1), Bouchut C(1), Vignal C(1). Author information: (1)Université de Lyon/Saint-Etienne , Neuro-PSI/ENES CNRS UMR 9197, France. 

Begging calls are signals of need used by young birds to elicit care from adults. Different theoretical frameworks have been proposed to understand this parent-offspring communication. But relationships between parental response and begging intensity, or between begging characteristics and proxies of a young's need remain puzzling. Few studies have considered the adjustment of nestling begging features to previous experience as a possible explanation of these discrepancies. In this study, we tested the effect of a heterospecific rearing environment on individual developmental trajectories of the acoustic structure of nestling begging calls. Fifty-two zebra finch chicks were fostered either to Bengalese finch or to zebra finch parents, and begging calls were recorded at several stages of nestling development. Acoustic analyses revealed that the development of the spectral features of the begging calls differed between experimental conditions: chicks reared by Bengalese finches produced higher pitched and less broadband begging calls than chicks reared by conspecific parents. Differences were stronger in males than females and were not explained by differences in growth rate. We conclude that nestling begging calls can be plastic in response to social interactions with parents. PMCID: PMC4680624 PMID: 26716009 [PubMed] 

7. Dev Neurobiol. 2015 Dec 29. doi: 10.1002/dneu.22373. [Epub ahead of print] 

Variation in social relationships relates to song preferences and EGR1 expression in a female songbird. 
Schubloom HE(1), Woolley SC(1,)(2). Author information: (1)Integrated Program in Neuroscience, McGill University, Montreal, QC, Canada. (2)Department of Biology, McGill University, Montreal, QC, Canada. 

Social experiences can profoundly shape social behavior and the underlying neural circuits. Across species, the formation of enduring social relationships is associated with both neural and behavioral changes. However, it remains unclear how longer-term relationships between individuals influence brain and behavior. Here, we investigated how variation in social relationships relates to variation in female preferences for and neural responses to song in a pair-bonding songbird. We assessed variation in the interactions between individuals in male-female zebra finch pairs and found that female preferences for their mate's song were correlated with the degree of affiliation and amount of socially-modulated singing, but not with the frequency of aggressive interactions. Moreover, variation in measures of pair quality and preference correlated with variation in the song-induced expression of EGR1, an immediate early gene related to neural activity and plasticity, in brain regions important for auditory processing and social behavior. For example, females with weaker preferences for their mate's song had greater EGR1 expression in the nucleus Taeniae, the avian homologue of the mammalian medial amygdala, in response to playback of their mate's courtship song. Our data indicate that the quality of social interactions within pairs relates to variation in song preferences and neural responses to ethologically relevant stimuli and lend insight into neural circuits sensitive to social information. This article is protected by copyright. All rights reserved. © 2015 Wiley Periodicals, Inc. PMID: 26713856 [PubMed - as supplied by publisher] 

8. Appl Environ Microbiol. 2015 Dec 28. pii: AEM.03402-15. [Epub ahead of print] 

High genetic diversity of Newcastle disease virus in wild and domestic birds in Northeastern China from 2013 to 2015 reveals potential epidemic trends. 
Zhang P(1), Xie G(1), Liu X(2), Ai L(1), Chen Y(1), Meng X(1), Bi Y(3), Chen J(4), Sun Y(5), Stoeger T(6), Ding Z(1), Yin R(7). Author information: (1)Department of Veterinary Preventive Medicine, College of Veterinary Medicine, Jilin University, Xi'an Road 5333, Changchun, Jilin 130062, China. (2)College of Food Science and Engineering, Jilin University, Xi'an Road 5333, Changchun, Jilin 130062, China. (3)CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China. (4)CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Hubei, China. (5)China Animal Health and Epidemiology Center, Qingdao, Nanjing Road 369, Qingdao, Shandong 266032, China. (6)Comprehensive Pneumology Center, Institute of Lung Biology and Disease (iLBD), Helmholtz Zentrum Muenchen, Ingolstaedter Landstrasse 1, D-85764 Neuherberg/Munich, Germany. (7)Department of Veterinary Preventive Medicine, College of Veterinary Medicine, Jilin University, Xi'an Road 5333, Changchun, Jilin 130062, China 

Newcastle disease (ND), caused by the virulent Newcastle disease virus (NDV), is one of the most important viral diseases of birds globally, but little is currently known regarding enzootic trends of NDV in Northeastern China, especially for class I viruses. Thus, we performed a surveillance study for NDV in Northeastern China from 2013 to 2015. A total 755 samples from wild and domestic birds in wetlands and live bird markets (LBMs) were collected and ten isolates of NDV were identified. Genetic and phylogenetic analyses showed that five isolates from LBMs belong to class I subgenotype 1b, two (one from wild birds and one from LBMs) belong to the vaccine-like class II genotype II, and three (all from wild birds) belong to class II subgenotype Ib. Interestingly, the five class I isolates had epidemiological connections with viruses from Southern, Eastern and Southeastern China. Our findings, together with recent prevalent trends of class I and virulent class II NDV in China, suggest possible virus transmission between wild and domestic birds and the potential for a NDV epidemic in the future. Copyright © 2015, American Society for Microbiology. All Rights Reserved. PMID: 26712543 [PubMed - as supplied by publisher] 

9. Conserv Biol. 2015 Dec 29. doi: 10.1111/cobi.12672. [Epub ahead of print] 

Using empirical models of species colonization under multiple threatening processes to identify complementary threat mitigation strategies. 
Tulloch AI(1), Mortelliti A(2), Kay G(2), Florance D(2), Lindenmayer D(2). Author information: (1)Fenner School of Environment and Society, The Australian National University, Canberra, ACT 2601, Australia. (2)Fenner School of Environment and Society, The Australian National University, Canberra, ACT 2601, Australia. 

Approaches to prioritize conservation actions are increasing in popularity. However, limited empirical evidence exists to inform: 1) for which species alternative actions might be most effective, and 2) what combination of threats, if mitigated simultaneously, would result in the best outcomes for biodiversity. This study demonstrates a way to prioritize threat mitigation at a regional scale using empirical evidence based on predicted changes to population dynamics - information that is lacking in most threat prioritization frameworks that rely on expert elicitation. We used dynamic occupancy models to investigate the effects of multiple threats (tree cover, grazing, and the presence of a hyperaggresive competitor, the Noisy Miner Manorina melanocephala), on bird population dynamics in an endangered woodland community in south-eastern Australia. The three threatening processes had both positive and negative effects on different species. We predicted patch colonization probabilities to estimate the benefit to each species of removing one or more threats. We then set an objective of finding the best complementary set of threat mitigation strategies that would maximize colonization of all species whilst ensuring that redundant actions with little benefit were avoided. The single action likely to result in highest colonization was increasing tree cover, resulting in an average increase in colonization of 5% across all species and 11% for declining species. Combining Noisy Miner control with restoring tree cover was likely to increase species colonization by 10-19% on average (for all species or just declining species respectively), and was a higher priority than changing grazing regimes. Guidance for prioritizing threat mitigation is critical in the face of cumulative threatening processes. By incorporating population dynamics in a priority threat management framework, our approach ensures funding is not wasted on ineffective management programs that target the wrong threats or species. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved. PMID: 26711716 [PubMed - as supplied by publisher] 

10. Mitochondrial DNA. 2015 Dec 29:1-2. [Epub ahead of print] 

Complete mitochondrial genome and phylogenetic analysis of the chimney swift, Chaetura pelagica. 
Xu XQ(1), Zhang K(1). Author information: (1)a BGI Education Center , University of Chinese Academy of Sciences , Shenzhen , China. 

The chimney swift (Chaetura pelagica) is a bird belonging to the swift family, Apodidae, a member of the genus Chaetur. Here, we report the complete mitogenome sequence of C. pelagica, which was 16 892 bp and contained 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and 1 non-coding control region. Phylogenic tree was constructed based on the complete mitogenome of C. pelagica and closely related 11 closely related species to estimate their phylogenic relationship and to approve the accuracy. The complete mitochondrial genome of the C. pelagica would provide more information for the research of C. pelagica and the evolution of Apodidae family. PMID: 26711320 [PubMed - as supplied by publisher] 

11. Nat Genet. 2015 Dec 29;48(1):7-8. doi: 10.1038/ng.3472. 

A flamboyant behavioral polymorphism is controlled by a lethal supergene. 
Jiggins CD(1). Author information: (1)Department of Zoology, University of Cambridge, Cambridge, UK. 

Two new studies show how highly divergent modes of male reproduction in a wading bird are controlled by alternate alleles at a single locus encompassing a 4.5-Mb inversion in the genome. The locus is an example of a 'supergene' controlling multiple complex phenotypes. PMID: 26711109 [PubMed - in process] 

12. Mitochondrial DNA. 2015 Dec 28:1-2. [Epub ahead of print] 

The complete mitochondrial genome of the fulvous parrotbill Paradoxornis fulvifrons (Passeriformes: Muscicapidae). 
Wen L(1,)(2), Yang X(2), Liao J(1), Fu Y(1), Dai B(1). Author information: (1)a Sichuan Institute Key Laboratory for Protecting Endangered Birds in the Southwest Mountains, College of Life Sciences, Leshan Normal University , Leshan , Sichuan , China and. (2)b Kunming Institute of Zoology, Chinese Academy of Sciences , Kunming , Yunnan , China. 

The complete mitochondrial genome of the fulvous parrotbill (Paradoxornis fulvifrons) has been determined from Illumina sequencing data. The circular genome is 17 059 bp long, comprising 37 genes (13 protein-coding genes/PCGs, 22 tRNA genes and two rRNA genes) and a putative control region. Except for COX1 with GTG as its start codon, all PCGs are initiated with the ATR (ATA/ATG) codons. One PCG (COX1) is terminated with AGG, three PCGs (COX3, ND2 and ND4) with the incomplete stop codon T--/TA-, while all the others with TAA. The 22 tRNAs range in size from 64 bp (tRNA-Ser) to 75 bp (tRNA-Leu). The two rRNAs are 982 bp (12S rRNA) and 1600 bp (16S rRNA) long, respectively. The putative control region is located between tRNA-Thr and tRNA-Pro genes with a length of 1235 bp. The base composition is biased (29.06% A, 31.10% C, 14.97% G and 24.87% T) with an overall A + T content of 53.93% ("light strand"). Phylogenetic analysis indicated that P. fulvifrons is closely related to the congeneric vinous-throated parrotbill (P. webbianus). PMID: 26710310 [PubMed - as supplied by publisher] 

13. J Neurochem. 2015 Dec 28. doi: 10.1111/jnc.13513. [Epub ahead of print] 

Region-Specific Rapid Regulation of Aromatase Activity in Zebra Finch Brain. 
Comito D(1), Pradhan DS(1), Karleen BJ(1), Schlinger BA(1). Author information: (1)Departments of Integrative Biology and Physiology & Ecology and Evolutionary Biology, Laboratory of Neuroendocrinology of the Brain Research Institute, UCLA, Los Angeles, CA. 

Recent studies demonstrate that rapid modulation of the estrogen synthetic enzyme aromatase, regulates hypothalamic (HYP) estrogen production and subsequent neurophysiology and reproductive behavior. In songbirds, in addition to expression in the HYP, aromatase is expressed at high levels in several brain regions notably in the hippocampus (HP) and caudomedial nidopallium (NCM), where estrogens affect learning and memory and auditory processing respectively. Previous studies, largely in quail HYP, show that aromatase activity is acutely down-regulated by Ca(2+) -dependent phosphorylation. Here, using zebra finches (Taeniopygia guttata), we ask if similar mechanisms are at work in the songbird HYP and if there are sex as well as regional differences in aromatase modulation. Using in vitro assays to measure activity in homogenates or in partially purified supernatants containing microsomes and synaptosomes of the HP, HYP and NCM, we examined effects of Ca(2+) , Mg(2+) , ATP, NADPH, and an inhibitor of kinase activity. We report a rapid down-regulation of aromatase activity in the presence of phosphorylating conditions across all three brain regions and both sexes. However, regional differences were seen in response to some phosphorylating factors, some of which were improved by partial purification of the homogenates. Furthermore, while low concentrations of ATP inhibited aromatase activity, unexpectedly, inhibition was no longer seen with high ATP concentrations. These results provide evidence for a regional and temporal specificity in the rapid modulation of aromatase activity that may bear on local neuroendocrine function. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved. PMID: 26709964 [PubMed - as supplied by publisher] 

14. Int J Parasitol. 2015 Dec 19. pii: S0020-7519(15)00330-6. doi: 10.1016/j.ijpara.2015.11.002. [Epub ahead of print] 

The more the merrier - experimental evidence for density-dependent feeding facilitation in the bird-specialised tick Ixodes arboricola. Van Oosten AR(1), Matthysen E(2), Heylen DJ(2). Author information: (1)University of Antwerp, Evolutionary Ecology Group, Groenenborgerlaan 171, B-2020 Antwerp, Belgium. Electronic address: (2)University of Antwerp, Evolutionary Ecology Group, Groenenborgerlaan 171, B-2020 Antwerp, Belgium. 

Similar to many other parasites, the distribution of ticks among hosts is strongly skewed, with few hosts harbouring the majority of parasites. Because parasite-induced impairment of host health, parasite population growth and pathogen transmission are density-dependent, understanding why tick distributions are skewed is important for the population and evolutionary dynamics of both parasite and host. However, there is currently no knowledge concerning parasites that strongly depend on individual hosts. Here, we investigated the effects of tick density on feeding performance in the nidicolous tree-hole tick, Ixodes arboricola, which feeds on cavity-nesting birds and is the carrier of several tick-borne pathogens. Nidicolous ticks reside in or close to their hosts' nests and therefore depend strongly on individual hosts and their offspring. Increased feeding success at higher densities (facilitation) may therefore be detrimental to the ticks themselves. We investigated the effects of tick density on feeding performance of I. arboricola by infesting great tit nestlings with one to five adult ticks, which is within the natural range. There was no effect of tick density on initial attachment success, attachment after 48h or engorgement weight, but tick recovery rates increased significantly with tick density. We also found a modest increase in nestling body mass with tick density, suggesting that birds over-compensate resource drainage by the ticks and, by doing this, anticipate the costs of a tick-rich environment. Our results indicate that nidicolous ticks perform better when feeding in aggregation. This may have important consequences for population dynamics and consequently pathogen transmission. Copyright © 2015. Published by Elsevier Ltd. PMID: 26709107 [PubMed - as supplied by publisher] 

15. Environ Pollut. 2015 Dec 18;210:145-154. doi: 10.1016/j.envpol.2015.12.016. [Epub ahead of print] 

Maternal transfer of contaminants in birds: Mercury and selenium concentrations in parents and their eggs. 
Ackerman JT(1), Eagles-Smith CA(2), Herzog MP(3), Hartman CA(3). Author information: (1)U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620, United States. Electronic address: (2)U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, 3200 SW Jefferson Way, Corvallis, OR 97331, United States. (3)U.S. Geological Survey, Western Ecological Research Center, Dixon Field Station, 800 Business Park Drive, Suite D, Dixon, CA 95620, United States. 

We conducted a detailed assessment of the maternal transfer of mercury and selenium to eggs in three bird species (n = 107 parents and n = 339 eggs), and developed predictive equations linking contaminant concentrations in eggs to those in six tissues of the mother (blood, muscle, liver, kidney, breast feathers, and head feathers). Mercury concentrations in eggs were positively correlated with mercury concentrations in each of the mother's internal tissues (R(2) ≥ 0.95), but generally not with feathers. For each species, the proportion of mercury transferred to eggs decreased as mercury concentrations in the mother increased. At the same maternal mercury concentration, the proportion of mercury transferred to eggs differed among species, such that Forster's tern (Sterna forsteri) and black-necked stilt (Himantopus mexicanus) females transferred more methylmercury to their eggs than American avocet (Recurvirostra americana) females. Selenium concentrations in eggs also were correlated with selenium concentrations in the mother's liver (R(2) = 0.87). Furthermore, mercury and selenium concentrations in tern eggs were positively correlated with those in the father (R(2) = 0.84). Incubating male terns had 21% higher mercury concentrations in blood compared to incubating females at the same egg mercury concentration. We provide equations to predict contaminant concentrations in eggs from each of the commonly sampled bird tissues. Published by Elsevier Ltd. PMID: 26708769 [PubMed - as supplied by publisher] 

16. Virology. 2015 Dec 18;489:63-74. doi: 10.1016/j.virol.2015.12.002. [Epub ahead of print] 

A diarrheic chicken simultaneously co-infected with multiple picornaviruses: Complete genome analysis of avian picornaviruses representing up to six genera. 
Boros Á(1), Pankovics P(1), Adonyi Á(1), Fenyvesi H(1), Day JM(2), Phan TG(3), Delwart E(3), Reuter G(4). Author information: (1)Regional Laboratory of Virology, National Reference Laboratory of Gastroenteric Viruses, ÁNTSZ Regional Institute of State Public Health Service, Pécs, Hungary and University of Pécs, Pécs, Hungary. (2)United States Department of Agriculture, Agricultural Research Service, U. S. National Poultry Research Center, Southeast Poultry Research Laboratory, Athens, GA, USA. (3)Blood Systems Research Institute, San Francisco, CA, USA; University of California, San Francisco, CA, USA. (4)Regional Laboratory of Virology, National Reference Laboratory of Gastroenteric Viruses, ÁNTSZ Regional Institute of State Public Health Service, Pécs, Hungary and University of Pécs, Pécs, Hungary. Electronic address: 

In this study all currently known chicken picornaviruses including a novel one (chicken phacovirus 1, KT880670) were identified by viral metagenomic and RT-PCR methods from a single specimen of a diarrheic chicken suffering from a total of eight picornavirus co-infections, in Hungary. The complete genomes of six picornaviruses were determined and their genomic and phylogenetic characteristics and UTR RNA structural models analyzed in details. Picornaviruses belonged to genera Sicinivirus (the first complete genome), Gallivirus, Tremovirus, Avisivirus and "Orivirus" (two potential genotypes). In addition, the unassigned phacoviruses were also detected in multiple samples of chickens in the USA. Multiple co-infections promote and facilitate the recombination and evolution of picornaviruses and eventually could contribute to the severity of the diarrhea in chicken, in one of the most important food sources of humans. Copyright © 2015 Elsevier Inc. All rights reserved. PMID: 26707271 [PubMed - as supplied by publisher] 

17. Microb Ecol. 2015 Dec 26. [Epub ahead of print] 

Microbial Genomics of a Host-Associated Commensal Bacterium in Fragmented Populations of Endangered Takahe. 
Grange ZL(1,)(2,)(3), Gartrell BD(4,)(5), Biggs PJ(4,)(6), Nelson NJ(7), Anderson M(8), French NP(4,)(6). Author information: (1)Allan Wilson Centre for Molecular Ecology and Evolution, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand. (2)mEpiLab, Infectious Disease Research Centre, Hopkirk Research Institute, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand. (3)Wildbase, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand. (4)Allan Wilson Centre for Molecular Ecology and Evolution, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand. (5)Wildbase, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand. (6)mEpiLab, Infectious Disease Research Centre, Hopkirk Research Institute, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North, New Zealand. (7)Allan Wilson Centre for Molecular Ecology and Evolution, School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand. (8)Allan Wilson Centre for Molecular Ecology and Evolution, New Zealand Institute for Advanced Study, Massey University, Albany, New Zealand. 

Isolation of wildlife into fragmented populations as a consequence of anthropogenic-mediated environmental change may alter host-pathogen relationships. Our understanding of some of the epidemiological features of infectious disease in vulnerable populations can be enhanced by the use of commensal bacteria as a proxy for invasive pathogens in natural ecosystems. The distinctive population structure of a well-described meta-population of a New Zealand endangered flightless bird, the takahe (Porphyrio hochstetteri), provided a unique opportunity to investigate the influence of host isolation on enteric microbial diversity. The genomic epidemiology of a prevalent rail-associated endemic commensal bacterium was explored using core genome and ribosomal multilocus sequence typing (rMLST) of 70 Campylobacter sp. nova 1 isolated from one third of the takahe population resident in multiple locations. While there was evidence of recombination between lineages, bacterial divergence appears to have occurred and multivariate analysis of 52 rMLST genes revealed location-associated differentiation of C. sp. nova 1 sequence types. Our results indicate that fragmentation and anthropogenic manipulation of populations can influence host-microbial relationships, with potential implications for niche adaptation and the evolution of micro-organisms in remote environments. This study provides a novel framework in which to explore the complex genomic epidemiology of micro-organisms in wildlife populations. PMID: 26707136 [PubMed - as supplied by publisher] 

18. Poult Sci. 2015 Dec 25. pii: pev350. [Epub ahead of print] 

Commercial Hy-Line W-36 pullet and laying hen venous blood gas and chemistry profiles utilizing the portable i-STAT®1 analyzer. 
Schaal TP(1), Arango J(2), Wolc A(3), Brady JV(4), Fulton JE(2), Rubinoff I(2), Ehr IJ(5), Persia ME(6), O'Sullivan NP(2). Author information: (1)Hy-Line International, PO Box 310, Dallas Center, IA 50063 (2)Hy-Line International, PO Box 310, Dallas Center, IA 50063. (3)Hy-Line International, PO Box 310, Dallas Center, IA 50063 Iowa State University, Department of Animal Science, Kildee Hall, Ames, IA 50011. (4)Oregon State University, Department of Comparative Health Services, Veterinary Biomedical Sciences, Magruder Hall, Corvallis, OR 97331. (5)Iowa State University, Department of Animal Science, Kildee Hall, Ames, IA 50011. (6)Iowa State University, Department of Animal Science, Kildee Hall, Ames, IA 50011 Virginia Polytechnic Institute and State University, Department of Animal and Poultry Sciences, Litton Reaves Hall, Blacksburg, VA 24061. 

Venous blood gas and chemistry reference ranges were determined for commercial Hy-Line W-36 pullets and laying hens utilizing the portable i-STAT®1 analyzer and CG8+ cartridges. A total of 632 samples were analyzed from birds between 4 and 110 wk of age. Reference ranges were established for pullets (4 to 15 wk), first cycle laying hens (20 to 68 wk), and second cycle (post molt) laying hens (70 to 110 wk) for the following traits: sodium (Na mmol/L), potassium (K mmol/L), ionized calcium (iCa mmol/L), glucose (Glu mg/dl), hematocrit (Hct% Packed Cell Volume [PCV]), pH, partial pressure carbon dioxide (PCO2 mm Hg), partial pressure oxygen (PO2 mm Hg), total concentration carbon dioxide (TCO2 mmol/L), bicarbonate (HCO3 mmol/L), base excess (BE mmol/L), oxygen saturation (sO2%), and hemoglobin (Hb g/dl). Data were analyzed using ANOVA to investigate the effect of production status as categorized by bird age. Trait relationships were evaluated by linear correlation and their spectral decomposition. All traits differed significantly among pullets and mature laying hens in both first and second lay cycles. Levels for K, iCa, Hct, pH, TCO2, HCO3, BE, sO2, and Hb differed significantly between first cycle and second cycle laying hens. Many venous blood gas and chemistry parameters were significantly correlated. The first 3 eigenvalues explained ∼2/3 of total variation. The first 2 principal components (PC) explained 51% of the total variation and indicated acid-balance and relationship between blood O2 and CO2. The third PC explained 16% of variation and seems to be related to blood iCa. Establishing reference ranges for pullet and laying hen blood gas and chemistry with the i-STAT®1 handheld unit provides a mechanism to further investigate pullet and layer physiology, evaluate metabolic disturbances, and may potentially serve as a means to select breeder candidates with optimal blood gas or chemistry levels on-farm. © The Author 2015. Published by Oxford University Press on behalf of the Poultry Science Association. PMID: 26706355 [PubMed - as supplied by publisher] 

19. Ecol Appl. 2015 Oct;25(7):1932-43. 

Dynamics of a recovering Arctic bird population: the importance of climate, density dependence, and site quality. 
Bruggeman JE, Swem T, Andersen DE, Kennedy PL, Nigro D. 

Intrinsic and extrinsic factors affect vital rates and population-level processes, and understanding these factors is paramount to devising successful management plans for wildlife species. For example, birds time migration in response, in part, to local and broadscale climate fluctuations to initiate breeding upon arrival to nesting territories, and prolonged inclement weather early in the breeding season can inhibit egg-laying and reduce productivity. Also, density-dependent regulation occurs in raptor populations, as territory size is related to resource availability. Arctic Peregrine Falcons (Falco peregrinus tundrius; hereafter Arctic peregrine) have a limited and northern breeding distribution, including the Colville River Special Area (CRSA) in the National Petroleum Reserve-Alaska, USA. We quantified influences of climate, topography, nest productivity, prey habitat, density dependence, and interspecific competition affecting Arctic peregrines in the CRSA by applying the Dail-Madsen model to estimate abundance and vital rates of adults on nesting cliffs from 1981 through 2002. Arctic peregrine abundance increased throughout the 1980s, which spanned the population's recovery from DDT-induced reproductive failure, until exhibiting a stationary trend in the 1990s. Apparent survival rate (i.e., emigration; death) was negatively correlated with the number of adult Arctic peregrines on the cliff the previous year, suggesting effects of density-dependent population regulation. Apparent survival and arrival rates (i.e., immigration; recruitment) were higher during years with earlier snowmelt and milder winters, and apparent survival was positively correlated with nesting season maximum daily temperature. Arrival rate was positively correlated with average Arctic peregrine productivity along a cliff segment from the previous year and initial abundance was positively correlated with cliff height. Higher cliffs with documented higher productivity (presumably indicative of higher-quality habitat), are a priority for continued protection from potential nearby development and disturbance to minimize population-level impacts. Climate change. may affect Arctic peregrines in multiple ways, including through access to more snow-free nest sites and a lengthened breeding season that may increase likelihood of nest success. Our work provides insight into factors affecting a population during and after recovery, and demonstrates how the Dail-Madsen model can be used for any unmarked population with multiple years of abundance data collected through repeated surveys. PMID: 26591458 [PubMed - indexed for MEDLINE]

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