Search birdRS Box

Search birdRS blog posts

Browse the Blog Posts

Or scan through the blog archive below for items of interest as only the latest post is shown below, thanks.

Wednesday, 25 February 2015

What's new for 'birdRS' in PubMed. February 2015, Week 3

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).
View complete results in PubMed (results may change over time).



PubMed Results




1. J Evol Biol. 2015 Feb 18. doi: 10.1111/jeb.12605. [Epub ahead of print]

Bird predation selects for wing shape and coloration in a damselfly.

Outomuro D1, Johansson F.
Author information:
Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, 752 36, Uppsala, Sweden.

Abstract

Wing shape is related to flight performance, which is expected to be under selection for improving flight behaviours such as predator avoidance. Moreover, wing conspicuousness, usually involved in sexual selection processes, is also relevant in terms of predation risk. In this study, we examined how predation by a passerine bird, the white wagtail Motacilla alba, selects wing shape and wing colour patch size in males of the banded demoiselle Calopteryx splendens. The wing colour patch is intra- and intersexually selected in the study species. In a field study, we compared wings of live damselflies to wings of predated damselflies which are always discarded after predation. Based on aerodynamic theory and a previous study on wing shape of territorial tactics in damselflies, we predicted an overall short and broad wing, with a concave front margin shape to be selected by predation. This shape would be expected to improve escaping ability. Moreover, we predicted that wing patch size should be negatively selected by predation. We found that selection operated differently on fore- and hindwings. In contrast to our predictions, predation favoured a slender general forewing shape. However, the predicted wing shape was favoured in hindwings. We also found selection favouring a narrower wing colour patch. Our results suggest different roles of fore- and hindwings in flight, as previously suggested for Calopteryx damselflies and shown for butterflies and moths. Forewings would be more involved in sustained flight and hindwings in flight manoeuvrability. Our results differ somehow from a recently published work in the same study system, but using another population, suggesting that selection can fluctuate across space, despite the simplicity of this predator-prey system. This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.
PMID: 25693863 [PubMed - as supplied by publisher]

Icon for Blackwell Publishing




2. Ecol Evol. 2015 Feb;5(3):781-98. doi: 10.1002/ece3.1400. Epub 2015 Jan 20.

Evolution of leaf warbler songs (Aves: Phylloscopidae).

Tietze DT1, Martens J2, Fischer BS3, Sun YH4, Klussmann-Kolb A5, Päckert M6.
Author information:
Institute of Ecology, Evolution and Diversity, Goethe University Max-von-Laue-Straße 13, 60439, Frankfurt am Main, Germany ; Institute of Pharmacy and Molecular Biotechnology, Heidelberg University Im Neuenheimer Feld 364, 69120, Heidelberg, Germany.
Institute of Zoology, Johannes Gutenberg University 55099, Mainz, Germany.
Institute of Ecology, Evolution and Diversity, Goethe University Max-von-Laue-Straße 13, 60439, Frankfurt am Main, Germany.
Key Laboratory of Animal Ecology and Conservation, Institute of Zoology, Chinese Academy of Sciences 100101, Beijing, China.
Institute of Ecology, Evolution and Diversity, Goethe University Max-von-Laue-Straße 13, 60439, Frankfurt am Main, Germany ; Zoologisches Forschungsmuseum Alexander Koenig Adenauerallee 160, 53113, Bonn, Germany.
Senckenberg Natural History Collections, Museum of Zoology Königsbrücker Landstraße 159, 01109, Dresden, Germany.

Abstract

Songs in passerine birds are important for territory defense and mating. Speciation rates in oscine passerines are so high, due to cultural evolution, that this bird lineage makes up half of the extant bird species. Leaf warblers are a speciose Old-World passerine family of limited morphological differentiation, so that songs are even more important for species delimitation. We took 16 sonographic traits from song recordings of 80 leaf warbler taxa and correlated them with 15 potentially explanatory variables, pairwise, and in linear models. Based on a well-resolved molecular phylogeny of the same taxa, all pairwise correlations were corrected for relatedness with phylogenetically independent contrasts and phylogenetic generalized linear models were used. We found a phylogenetic signal for most song traits, but a strong one only for the duration of the longest and of the shortest element, which are presumably inherited instead of learned. Body size of a leaf warbler species is a constraint on song frequencies independent of phylogeny. At least in this study, habitat density had only marginal impact on song features, which even disappeared through phylogenetic correction. Maybe most leaf warblers avoid the deterioration through sound propagation in dense vegetation by singing from exposed perches. Latitudinal (and longitudinal) extension of the breeding ranges was correlated with most song features, especially verse duration (longer polewards and westwards) and complexity (lower polewards). Climate niche or expansion history might explain these correlations. The number of different element types per verse decreases with elevation, possibly due to fewer resources and congeneric species at higher elevations.
PMCID: PMC4328779 Free Article
PMID: 25691998 [PubMed]

Icon for John Wiley & Sons, Inc.





3. Ecol Evol. 2015 Feb;5(3):759-68. doi: 10.1002/ece3.1387. Epub 2015 Jan 17.

No species is an island: testing the effects of biotic interactions on models of avian niche occupation.

Morelli F1, Tryjanowski P2.
Author information:
Faculty of Biological Sciences, University of Zielona Gora Prof. Z. Szafrana St. 1, Zielona Gora, 65-516, Poland ; Faculty of Environmental Sciences, Department of Applied Geoinformatics and Spatial Planning, Czech University of Life Sciences Prague Kamýcká 129, Prague 6, 165 00, Czech Republic.
Institute of Zoology, Poznan University of Life Sciences Wojska Polskiego 71 C, Poznań, 60-625, Poland.

Abstract

Traditionally, the niche of a species is described as a hypothetical 3D space, constituted by well-known biotic interactions (e.g. predation, competition, trophic relationships, resource-consumer interactions, etc.) and various abiotic environmental factors. Species distribution models (SDMs), also called "niche models" and often used to predict wildlife distribution at landscape scale, are typically constructed using abiotic factors with biotic interactions generally been ignored. Here, we compared the goodness of fit of SDMs for red-backed shrike Lanius collurio in farmlands of Western Poland, using both the classical approach (modeled only on environmental variables) and the approach which included also other potentially associated bird species. The potential associations among species were derived from the relevant ecological literature and by a correlation matrix of occurrences. Our findings highlight the importance of including heterospecific interactions in improving our understanding of niche occupation for bird species. We suggest that suite of measures currently used to quantify realized species niches could be improved by also considering the occurrence of certain associated species. Then, an hypothetical "species 1" can use the occurrence of a successfully established individual of "species 2" as indicator or "trace" of the location of available suitable habitat to breed. We hypothesize this kind of biotic interaction as the "heterospecific trace effect" (HTE): an interaction based on the availability and use of "public information" provided by individuals from different species. Finally, we discuss about the incomes of biotic interactions for enhancing the predictive capacities on species distribution models.
PMCID: PMC4328777 Free Article
PMID: 25691996 [PubMed]

Icon for John Wiley & Sons, Inc. 




4. Ecol Evol. 2015 Jan;5(2):450-8. doi: 10.1002/ece3.1355. Epub 2015 Jan 2.

All you can eat: is food supply unlimited in a colonially breeding bird?

Hoi H1, Krištofík J2, Darolová A2.
Author information:
Department of Integrative Biology and Evolution, Konrad Lorenz Institute of Ethology, University of Veterinary Medicine Vienna, Austria.
Institute of Zoology, Slovak Academy of Sciences Bratislava, Slovakia.

Abstract

Food availability is generally considered to determine breeding site selection and therefore plays an important role in hypotheses explaining the evolution of colony formation. Hypotheses trying to explain why birds join a colony usually assume that food is not limited, whereas those explaining variation in colony size suggest that food is under constraint. In this study, we investigate the composition and amount of food items not eaten by the nestlings and found in nest burrows of colonially nesting European bee-eaters (Merops apiaster). We aimed to determine whether this unconsumed food is an indicator of unlimited food supply, the result of mistakes during food transfer between parents and chicks or foraging selectivity of chicks. Therefore, we investigated the amount of dropped food for each nest in relation to reproductive performance and parameters reflecting parental quality. Our data suggest that parents carry more food to the nest than chicks can eat and, hence, food is not limited. This assumption is supported by the facts that there is a positive relationship between dropped food found in a nest and the number of fledglings, nestling age, and chick health condition and that the amount of dropped food is independent of colony size. There is variation in the amount of dropped food within colonies, suggesting that parent foraging efficiency may also be an important determinant. Pairs nesting in the center of a colony performed better than those nesting on the edge, which supports the assumption that quality differences between parents are important as well. However, dropped food cannot be used as an indicator of local food availability as (1) within-colony variation in dropped food is larger than between colony variation and, (2) the average amount of dropped food is not related to colony size.
PMCID: PMC4314275 Free Article
PMID: 25691970 [PubMed]

Icon for John Wiley & Sons, Inc. 




5. Ecol Evol. 2015 Jan;5(2):345-56. doi: 10.1002/ece3.1345. Epub 2014 Dec 24.

Rainfall during parental care reduces reproductive and survival components of fitness in a passerine bird.

Öberg M1, Arlt D1, Pärt T1, Laugen AT2, Eggers S1, Low M1.
Author information:
Department of Ecology, Swedish University of Agricultural Sciences Box 7044, Uppsala, 75007, Sweden.
Department of Ecology, Swedish University of Agricultural Sciences Box 7044, Uppsala, 75007, Sweden ; Aronia Coastal Zone Research Team, Novia University of Applied Sciences & Åbo Academy University Raseborgsvägen 9, Ekenäs, 10600, Finland.

Abstract

Adverse weather conditions during parental care may have direct consequences for offspring production, but longer-term effects on juvenile and parental survival are less well known. We used long-term data on reproductive output, recruitment, and parental survival in northern wheatears (Oenanthe oenanthe) to investigate the effects of rainfall during parental care on fledging success, recruitment success (juvenile survival), and parental survival, and how these effects related to nestling age, breeding time, habitat quality, and parental nest visitation rates. While accounting for effects of temperature, fledging success was negatively related to rainfall (days > 10 mm) in the second half of the nestling period, with the magnitude of this effect being greater for breeding attempts early in the season. Recruitment success was, however, more sensitive to the number of rain days in the first half of the nestling period. Rainfall effects on parental survival differed between the sexes; males were more sensitive to rain during the nestling period than females. We demonstrate a probable mechanism driving the rainfall effects on reproductive output: Parental nest visitation rates decline with increasing amounts of daily rainfall, with this effect becoming stronger after consecutive rain days. Our study shows that rain during the nestling stage not only relates to fledging success but also has longer-term effects on recruitment and subsequent parental survival. Thus, if we want to understand or predict population responses to future climate change, we need to consider the potential impacts of changing rainfall patterns in addition to temperature, and how these will affect target species' vital rates.
PMCID: PMC4314267 Free Article
PMID: 25691962 [PubMed]

Icon for John Wiley & Sons, Inc. 




6. Evolution. 2015 Feb 17. doi: 10.1111/evo.12625. [Epub ahead of print]

Hatching asynchrony aggravates inbreeding depression in a songbird (Serinus canaria): An inbreeding-environment interaction.

de Boer RA1, Eens M, Fransen E, Müller W.
Author information:
Faculty of Science - Ethology - University of Antwerp, Universiteitsplein 1 - Campus Drie Eiken C1.25, B-2610, Wilrijk, Belgium. raissa.deboer@uantwerpen.be.

Abstract

Understanding how the intensity of inbreeding depression is influenced by stressful environmental conditions is an important area of enquiry in various fields of biology. In birds, environmental stress during early development is often related to hatching asynchrony; differences in age, and thus size, impose a gradient in conditions ranging from benign (first hatched chick) to harsh (last hatched chick). Here, we compared the effect of hatching order on growth rate in inbred (parents are full siblings) and outbred (parents are unrelated) canary chicks (Serinus canaria). We found that inbreeding depression was more severe under more stressful conditions, being most evident in later hatched chicks. Thus, consideration of inbreeding-environment interactions is of vital importance for our understanding of the biological significance of inbreeding depression and hatching asynchrony. The latter is particularly relevant given that hatching asynchrony is a widespread phenomenon, occurring in many bird species. The exact causes of the observed inbreeding-environment interaction are as yet unknown, but may be related to a decrease in maternal investment in egg contents with laying position (i.e. pre-hatching environment), or to performance of the chicks during sibling competition and/or their resilience to food shortage (i.e. post-hatching environment). This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.
PMID: 25689753 [PubMed - as supplied by publisher]




7. Med Vet Entomol. 2015 Feb 16. doi: 10.1111/mve.12108. [Epub ahead of print]

Host preferences of ornithophilic biting midges of the genus Culicoides in the Eastern Balkans.

Bobeva A1, Zehtindjiev P, Ilieva M, Dimitrov D, Mathis A, Bensch S.
Author information:
Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, Sofia, Bulgaria.

Abstract

Many biting midges of the genus Culicoides Latreille, 1809 (Diptera: Ceratopogonidae) are competent vectors of a diverse number of pathogens. The identification of their feeding behaviour and of vector-host associations is essential for understanding their transmission capacity. By applying two different nested polymerase chain reaction (PCR) assays, of which one targeted the avian cyt b gene and the other targeted the COI gene of a wide range of vertebrates, we identified the blood hosts of six biting midge species including Culicoides circumscriptus, Culicoides festivipennis, Culicoides punctatus, Culicoides pictipennis, Culicoides alazanicus and Culicoides cf. griseidorsum, the latter two of which are reported in Bulgaria for the first time. Bird DNA was found in 50.6% of 95 investigated bloodmeals, whereas mammalian DNA was identified in 13.7%. Two Culicoides species were found to feed on both birds and mammals. There was remarkable diversity in the range of avian hosts: 23 species from four orders were identified in the abdomens of four Culicoides species. The most common bird species identified was the magpie, Pica pica (n = 7), which was registered in all four ornithophilic biting midge species. Six bloodmeals from the great tit, Parus major, were recorded only in C. alazanicus. None of the studied species of Culicoides appeared to be restricted to a single avian host.
© 2015 The Royal Entomological Society.
PMID: 25689114 [PubMed - as supplied by publisher]




8. Glob Chang Biol. 2015 Feb 16. doi: 10.1111/gcb.12862. [Epub ahead of print]

Vocal traits and diet explain avian sensitivities to anthropogenic noise.

Francis CD1.
Author information:
National Evolutionary Synthesis Center, Durham, NC, 27705, USA; Department of Biological Sciences, California Polytechnic State University, San Luis Obispo, CA, 93407, USA.

Abstract

Global population growth has caused extensive human-induced environmental change, including a near-ubiquitous transformation of the acoustical environment due to the propagation of anthropogenic noise. Because the acoustical environment is a critical ecological dimension for countless species to obtain, interpret and respond to environmental cues, highly novel environmental acoustics have the potential to negatively impact organisms that use acoustics for a variety of functions, such as communication and predator/prey detection. Using a comparative approach with 308 populations of 183 bird species from 14 locations in Europe, North American and the Caribbean, I sought to reveal the intrinsic and extrinsic factors responsible for avian sensitivities to anthropogenic noise as measured by their habitat use in noisy versus adjacent quiet locations. Birds across all locations tended to avoid noisy areas, but trait-specific differences emerged. Vocal frequency, diet and foraging location predicted patterns of habitat use in response to anthropogenic noise, but body size, nest placement and type, other vocal features and the type of anthropogenic noise (chronic industrial vs. intermittent urban/traffic noise) failed to explain variation in habitat use. Strongly supported models also indicated the relationship between sensitivity to noise and predictive traits had little to no phylogenetic structure. In general, traits associated with hearing were strong predictors - species with low-frequency vocalizations, which experience greater spectral overlap with low-frequency anthropogenic noise tend to avoid noisy areas, whereas species with higher frequency vocalizations respond less severely. Additionally, omnivorous species and those with animal-based diets were more sensitive to noise than birds with plant-based diets, likely because noise may interfere with the use of audition in multimodal prey detection. Collectively, these results suggest that anthropogenic noise is a powerful sensory pollutant that can filter avian communities nonrandomly by interfering with birds' abilities to receive, respond to and dispatch acoustic cues and signals.
© 2015 John Wiley & Sons Ltd.
PMID: 25688983 [PubMed - as supplied by publisher]

Icon for John Wiley &  Sons, Inc.









9. Oecologia. 2015 Feb 18. [Epub ahead of print]

Changes in the apparent survival of a tropical bird in response to the El Niño Southern Oscillation in mature and young forest in Costa Rica.

Wolfe JD1, Ralph CJ, Elizondo P.
Author information:
USDA Forest Service, Pacific Southwest Research Station, Arcata, USA, jdw@klamathbird.org.

Abstract

The effects of habitat alteration and climatic instability have resulted in the loss of bird populations throughout the globe. Tropical birds in particular may be sensitive to climate and habitat change because of their niche specialization, often sedentary nature, and unique life-cycle phenologies. Despite the potential influence of habitat and climatic interactions on tropical birds, we lack comparisons of avian demographics from variably aged forests subject to different climatic phenomena. Here, we measured relationships between forest type and climatic perturbations on White-collared Manakin (Manacus candei), a frugivorous tropical bird, by using 12 years of capture data in young and mature forests in northeastern Costa Rica. We used Cormack-Jolly-Seber models and an analysis of deviance to contrast the influence of the El Niño Southern Oscillation (ENSO) on manakin survival. We found that ENSO had little effect on manakin survival in mature forests. Conversely, in young forests, ENSO explained 79 % of the variation where dry El Niño events negatively influenced manikin survival. We believe mature forest mitigated negative effects of dry El Niño periods and can serve as refugia for some species by buffering birds from climatic instability. Our results represent the first published documentation that ENSO influences the survival of a resident Neotropic landbird.
PMID: 25687831 [PubMed - as supplied by publisher]

Icon for Springer









10. Gigascience. 2014 Dec 11;3(1):32. doi: 10.1186/2047-217X-3-32. eCollection 2014.

The birds of Genome10K.

Author information:
Theodosius Dobzhansky Center for Genome Bioinformatics, St. Petersburg State University, St. Petersburg, 199004 Russia ; Oceanographic Center, Nova Southeastern University, Ft Lauderdale, FL 33004 USA.
Department of Biomolecular Engineering, University of California, Santa Cruz, CA 95064 USA.
San Diego Zoo Institute for Conservation Research, Escondido, CA 92027 USA.

Abstract

Everyone loves the birds of the world. From their haunting songs and majesty of flight to dazzling plumage and mating rituals, bird watchers - both amateurs and professionals - have marveled for centuries at their considerable adaptations. Now, we are offered a special treat with the publication of a series of papers in dedicated issues of Science, Genome Biology and GigaScience (which also included pre-publication data release). These present the successful beginnings of an international interdisciplinary venture, the Avian Phylogenomics Project that lets us view, through a genomics lens, modern bird species and the evolutionary events that produced them.
PMCID: PMC4326320 Free PMC Article
PMID: 25685332 [PubMed]






11. Methods Ecol Evol. 2015 Jan 1;6(1):109-118.

Decomposing changes in phylogenetic and functional diversity over space and time.

Chalmandrier L1, Münkemüller T1, Devictor V2, Lavergne S1, Thuiller W1.
Author information:
Univ. Grenoble Alpes, LECA, F-38000 Grenoble, France ; CNRS, LECA, F-38000 Grenoble, France.
Institut des Sciences de l'Évolution de Montpellier, UMR CNRS 5554, Université Montpellier 2, Place Eugène Bataillon, 34095 Montpellier Cedex 05, France.

Abstract

The α, β, γ diversity decomposition methodology is commonly used to investigate changes in diversity over space or time but rarely conjointly. However, with the ever-increasing availability of large-scale biodiversity monitoring data, there is a need for a sound methodology capable of simultaneously accounting for spatial and temporal changes in diversity.Using the properties of Chao's index, we adapted Rao's framework of diversity decomposition between orthogonal dimensions to a multiplicative α, β, γ decomposition of functional or phylogenetic diversity over space and time, thereby combining their respective properties. We also developed guidelines for interpreting both temporal and spatial β-diversities and their interaction.We characterised the range of β-diversity estimates and their relationship to the nested decomposition of diversity. Using simulations, we empirically demonstrated that temporal and spatial β-diversities are independent from each other and from α and γ-diversities when the study design is balanced, but not otherwise. Furthermore, we showed that the interaction term between the temporal and the spatial β-diversities lacked such properties.We illustrated our methodology with a case study of the spatio-temporal dynamics of functional diversity in bird assemblages in four regions of France. Based on these data, our method makes it possible to discriminate between regions experiencing different diversity changes in time. Our methodology may therefore be valuable for comparing diversity changes over space and time using large-scale datasets of repeated surveys.
PMCID: PMC4326675 Free PMC Article
PMID: 25685310 [PubMed]




12. Mol Phylogenet Evol. 2015 Feb 12. pii: S1055-7903(15)00032-9. doi: 10.1016/j.ympev.2015.02.004. [Epub ahead of print]

Molecular phylogeny and diversification of a widespread Neotropical rainforest bird group: The Buff-throated Woodcreeper complex, Xiphorhynchus guttatus/susurrans (Aves: Dendrocolaptidae).

Rocha TC1, Sequeira F2, Aleixo A3, Rêgo PS4, Sampaio I4, Schneider H4, Vallinoto M5.
Author information:
Laboratório de Evolução, Instituto de Estudos Costeiros, Universidade Federal do Pará, Bragança, PA 68600-000, Brazil.
CIBIO-InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Campus Agrário de Vairão, Universidade do Porto, Vairão 4485-661, Portugal.
Coordenação de Zoologia, Museu Paraense Emílio Goeldi, Caixa Postal 399, Belém, PA 66077 530, Brazil.
Laboratório de Genética e Biologia Molecular, Instituto de Estudos Costeiros, Universidade Federal do Pará, Bragança, PA 68600-000, Brazil.
Laboratório de Evolução, Instituto de Estudos Costeiros, Universidade Federal do Pará, Bragança, PA 68600-000, Brazil; CIBIO-InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Campus Agrário de Vairão, Universidade do Porto, Vairão 4485-661, Portugal. Electronic address: mvallino@ufpa.br.

Abstract

The genus Xiphorhynchus is a species rich avian group widely distributed in Neotropical forests of Central and South America. Although recent molecular studies have improved our understanding of the spatial patterns of genetic diversity in some species of this genus, most are still poorly known, including their taxonomy. Here, we address the historical diversification and phylogenetic relationships of the X. guttatus/susurrans complex, using data from two mitochondrial (cyt b and ND2) and one nuclear (β-fibint7) genes. Phylogenetic relationships were inferred with both gene trees and a Bayesian-based species tree under a coalescent framework (∗BEAST). With exception of the nuclear β-fibint7 gene that produced an unresolved tree, both mtDNA and the species tree showed a similar topology and were congruent in recovering five main clades with high statistical support. These clades, however, are not fully concordant with traditional delimitation of some X. guttatus subspecies, since X. g. polystictus, X. g. guttatus, and X. connectens are not supported as distinct clades. Interestingly, these three taxa are more closely related to the mostly trans-Andean X. susurrans than the other southern and western Amazonian subspecies of X. guttatus, which constitutes a paraphyletic species. Timing estimates based on the species tree indicated that diversification in X. guttatus occurred between the end of the Pliocene and early Pleistocene, likely associated with the formation of the modern Amazon River and its main southern tributaries (Xingu, Tocantins, and Madeira), in addition to climate-induced changes in the distribution of rainforest biomes. Our study supports with an enlarged dataset a previous proposal for recognizing at least three species level taxa in the X. guttatus/susurrans complex: X. susurrans, X. guttatus, and X. guttatoides.
Copyright © 2015 Elsevier Inc. All rights reserved.
PMID: 25683049 [PubMed - as supplied by publisher]

Icon for Elsevier Science




13. Ticks Tick Borne Dis. 2015 Feb 11. pii: S1877-959X(15)00017-5. doi: 10.1016/j.ttbdis.2015.01.004. [Epub ahead of print]

Molecular identification of Ehrlichia species and host bloodmeal source in Amblyomma americanum L. from two locations in Tennessee, United States.

Harmon JR1, Scott MC2, Baker EM2, Jones CJ3, Hickling GJ2.
Author information:
University of Tennessee Institute of Agriculture, Entomology and Plant Pathology Department, United States; University of Tennessee Institute of Agriculture, Center for Wildlife Health, United States. Electronic address: jharmon4@gmail.com.
University of Tennessee Institute of Agriculture, Center for Wildlife Health, United States.
University of Tennessee Institute of Agriculture, Entomology and Plant Pathology Department, United States.

Abstract

The current status of tick-borne diseases in the southeastern United States is challenging to define due to emerging pathogens, uncertain tick/host relationships, and changing disease case definitions. A golf-oriented retirement community on the Cumberland Plateau in Tennessee experienced an ehrlichiosis outbreak in 1993, prompting efforts to reduce the local tick population using '4-Poster' acaricide devices targeting white-tailed deer (Odocoileus virginianus). In 2009, the prevalence of Ehrlichia spp. in questing ticks was surveyed in the area and compared to a Tennessee state park where acaricide had not been applied. The range of wildlife hosts that immature Amblyomma americanum fed upon and the role that these hosts may play in pathogen dynamics were investigated using a reverse line blot (RLB) bloodmeal analysis technique. Amblyomma americanum was by far the most common tick species in both study areas (>99% of ticks collected). Of 303 adult and nymphal A. americanum tested at the retirement community, six were positive for Ehrlichia chaffeensis (2.0%), 16 were positive for E. ewingii (5.3%), and six were positive for Panola Mountain Ehrlichia (2.0%). This is the first confirmation of Panola Mountain Ehrlichia in A. americanum from the state of Tennessee. The 9.3% prevalence of Ehrlichia spp. in ticks from the retirement community was similar to that detected at the state park site (5.5%), suggesting that the 4-Poster treatment had not been sufficient to reduce Ehrlichia spp. cycling in the tick population. At both study sites, A. americanum fed on a wide range of mammal and bird species, with a minority of detectable bloodmeals coming from deer. Of the Ehrlichia-infected nymphs with positive bloodmeal identification, none fed on deer, indicating that multiple vertebrate species are contributing to sylvatic maintenance of Ehrlichia spp. at these sites. This highlights the difficulty of attempting to reduce the risk of tick-borne disease through host-targeted interventions alone.
Copyright © 2015 Elsevier GmbH. All rights reserved.
PMID: 25682494 [PubMed - as supplied by publisher]

Icon for Elsevier Science




14. Poult Sci. 2015 Feb 12. pii: pev021. [Epub ahead of print]

Welfare and performance in layers following temporary exclusion from the litter area on introduction to the layer facility.

Alm M1, Wall H2, Holm L3, Wichman A4, Palme R5, Tauson R2.
Author information:
Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, Box 7024, SE-750 07 Uppsala, Sweden malin.alm@slu.se.
Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, Box 7024, SE-750 07 Uppsala, Sweden.
Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Box 7011, SE-750 07 Uppsala, Sweden.
Department of Animal Environment and Health, Swedish University of Agricultural Sciences, Box 7068, SE-750 07 Uppsala, Sweden.
Department of Biomedical Sciences/Unit of Physiology, Pathophysiology, and Experimental Endocrinology, University of Veterinary Medicine, Veterinärplatz 1, 1210 Vienna, Austria.

Abstract

When introduced to the laying facility, pullets are sometimes temporarily excluded from the litter area in order to help them locate food and water, and to prevent floor-laid eggs. This procedure is not permitted in Sweden, because it involves denying access to both litter and space, which may have a negative effect on bird welfare. The present study investigated how the welfare and performance of layers were affected by this temporary exclusion on introduction of hens to the laying facility. The study included 600 floor-reared Dekalb White layers obtained at 16 wk age and housed in 6 groups of 100 in a conventional single-tier floor-laying system. Birds were either given full access to the litter area during the whole study or were excluded from the litter area during the first 2 wk after transfer to the laying facility. From 18 to 72 wk age, birds in both treatments had full access to the litter area. Excluding birds from the litter area for 2 wk resulted in better feather cover and reduced fearfulness, according to novel object and tonic immobility tests. Furthermore, birds initially excluded from the litter area produced eggs with a lower proportion of shell irregularities than birds with full access to the litter area throughout. No difference was found in corticosterone metabolites in droppings rate of lay, mortality, or proportion of floor-laid eggs. In conclusion, none of the parameters studied indicated that the welfare of laying hens was compromised by temporary exclusion from the litter area on introduction to the laying facility. In fact, some of the data suggested that bird welfare had improved.
© 2015 Poultry Science Association Inc.
PMID: 25681475 [PubMed - as supplied by publisher]

Icon for HighWire






No comments:

Post a Comment