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1.
Anim Genet ; 50(5): 475-483, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31305959

RESUMO

Ten indigenous chicken breeds were originally distributed in Jiangxi Province, China, and they define a critical component of Chinese chicken genetic resources. We have investigated the population genetics of seven Jiangxi chicken breeds using 600K chicken BeadChip SNP data. To provide a genome-wide perspective for the population structure of all 10 Jiangxi chicken breeds, we herein genotyped 78 additional individuals from the seven breeds and 63 chickens from three uninvestigated breeds-Yugan Black (YG), Nancheng Black (NC) and Wanzai Yellow using 55K chicken SNP arrays. We then explored merged data of 17 101 SNPs from 235 individuals to infer the population structure of the 10 breeds. We showed that NC and YG are two regional populations of the same breed, as individuals from the two populations clustered together to form a branch separate from the other breeds in the neighbor-joining tree, they always grouped together in multidimensional principal component analyses and they displayed an identical pattern of ancestral lineage composition. Hence, NC and YG should be considered a single breed in the state-supported conservation scheme. Moreover, we conducted a genome scan for signatures of selection for black plumage. bayescan and hapflk analyses of two contrasting groups (three black-feathered breeds vs. six non-black-feathered breeds) consistently detected 25 putative regions under selection. Nine pigmentation- associated genes (DCT, SLC24A5, SLC30A4, MYO5A, CYP19A1, NADK2, SLC45A2, GNAQ and DCP2) reside within these regions, and these genes are interesting candidates for black plumage and provide a starting point for further identification of causative mutations for black feathers in chicken.


Assuntos
Galinhas/classificação , Galinhas/genética , Plumas/fisiologia , Animais , Galinhas/fisiologia , China , Variação Genética , Estudo de Associação Genômica Ampla , Pigmentação , Polimorfismo de Nucleotídeo Único
2.
Nat Commun ; 10(1): 1773, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30992444

RESUMO

Sexual selection is proposed to be a powerful driver of phenotypic evolution in animal systems. At macroevolutionary scales, sexual selection can theoretically drive both the rate and direction of phenotypic evolution, but this hypothesis remains contentious. Here, we find that differences in the rate and direction of plumage colour evolution are predicted by a proxy for sexual selection intensity (plumage dichromatism) in a large radiation of suboscine passerine birds (Tyrannida). We show that rates of plumage evolution are correlated between the sexes, but that sexual selection has a strong positive effect on male, but not female, interspecific divergence rates. Furthermore, we demonstrate that rapid male plumage divergence is biased towards carotenoid-based (red/yellow) colours widely assumed to represent honest sexual signals. Our results highlight the central role of sexual selection in driving avian colour divergence, and reveal the existence of convergent evolutionary responses of animal signalling traits under sexual selection.


Assuntos
Evolução Biológica , Plumas/fisiologia , Preferência de Acasalamento Animal/fisiologia , Passeriformes/fisiologia , Pigmentação/fisiologia , Animais , Carotenoides/metabolismo , Cor , Conjuntos de Dados como Assunto , Masculino , Filogenia , Caracteres Sexuais
3.
Nat Commun ; 10(1): 1602, 2019 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-30962513

RESUMO

Organismal appearances are shaped by selection from both biotic and abiotic drivers. For example, Gloger's rule describes the pervasive pattern that more pigmented populations are found in more humid areas. However, species may also converge on nearly identical colours and patterns in sympatry, often to avoid predation by mimicking noxious species. Here we leverage a massive global citizen-science database to determine how biotic and abiotic factors act in concert to shape plumage in the world's 230 species of woodpeckers. We find that habitat and climate profoundly influence woodpecker plumage, and we recover support for the generality of Gloger's rule. However, many species exhibit remarkable convergence explained neither by these factors nor by shared ancestry. Instead, this convergence is associated with geographic overlap between species, suggesting occasional strong selection for interspecific mimicry.


Assuntos
Evolução Biológica , Mimetismo Biológico/fisiologia , Aves/fisiologia , Plumas/fisiologia , Simpatria/fisiologia , Animais , Clima , Cor , Ecossistema , Feminino , Masculino , Filogenia , Caracteres Sexuais
4.
Poult Sci ; 98(6): 2474-2488, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30715510

RESUMO

In this study, the effects of environmental enrichment, stocking density, and microclimate on feather condition, skin injuries, and other health parameters were investigated. During 2 rearing periods (RP), non-beak-trimmed Lohmann Brown hybrid pullets were housed in an aviary system for rearing with cages and from week 5 of age onwards with access to a litter area. All pullets were reared in the same barn and under practical conditions. In total, 9,187 (RP 1) and 9,090 (RP 2) pullets were distributed in 9 units, and each unit was assigned to 1 of 3 experimental groups (EG). In the control group (EG 1), the pullets were kept without environmental enrichment and at a commonly used stocking density (22 to 23 pullets per m²). Each unit of the 2 treatment groups was provided with 3 types of environmental enrichment simultaneously (pecking stones, pecking blocks, and lucerne bales), and the pullets were kept at a lower than usual (18 pullets per m²) (EG 2) or commonly used stocking density (EG 3). In each RP, the plumage condition, injuries and health of the pullets, and the microclimate of the housing system were examined 5 times. The statistical relationships of enrichment, stocking density, and microclimate with animal health were estimated via regression models. We found that the provision of environmental enrichment had a significant increasing effect on the plumage quality in week 17. Furthermore, significant relationships were found between several predictors (temperature in the housing system, dust concentration, and age of the pullets) and response variables (plumage condition, body injuries, head injuries, bodyweight, difference to the target weight and uniformity). The results of this study showed that increasing temperature in the housing system and increasing age of the pullets are significantly associated with the occurrence of feather damage and skin injuries during rearing. With stocking densities as high as we used (all > 17 pullets per m²), no significant positive effect of a reduced stocking density could be observed.


Assuntos
Criação de Animais Domésticos/métodos , Galinhas/fisiologia , Plumas/fisiologia , Abrigo para Animais , Microclima , Animais , Feminino , Alemanha , Densidade Demográfica
5.
Mar Pollut Bull ; 138: 135-144, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30660254

RESUMO

Feather fouling is a primary cause of seabird mortality during marine hydrocarbon oil spills. Understanding how oils interact with feathers is an important step in mitigating this threat. Seabird feathers from 12 taxa, representing most seabird families from the tropics and southern latitudes, were exposed to crude and condensate oil films under laboratory settings. Feathers were measured for changes in mass proportional to feather size, and for barbule clumping. Seabird feathers from six distinct families exposed to very thin oil sheens (<0.3 µm) showed no significant change in proportional mass relative to control treatments, and 10 of the 12 species exposed to these films revealed no significant difference in barbule clumping. By contrast, exposure to both crude and condensate oil films ≥3 µm resulted in significant increases in feather mass and clumping. Our findings highlight the importance of considering the influence of oil on feather structure when compiling threat assessments involving seabirds.


Assuntos
Aves , Plumas/efeitos dos fármacos , Plumas/fisiologia , Petróleo/toxicidade , Animais , Clima , Poluição por Petróleo , Água do Mar , Clima Tropical , Viscosidade
6.
J Colloid Interface Sci ; 541: 56-64, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30682593

RESUMO

HYPOTHESIS: Flying in the rain presents a greater challenge for smaller animals such as kingfishers, compared with aircraft in the same situation. Regardless, kingfishers have developed advanced water repellency as reflected in the hydrophobicity and elasticity of their feathers. Therefore, it is possible to confirm that the elastic superhydrophobic surface can enhance the water repellency of the surface by experimental and theoretical analysis. EXPERIMENTS: A simplified device simulating droplet impact on a kingfisher feather was configured for comparison. Moreover, the dynamic behavior of droplets (with varying Weber numbers-2 ≤ We ≤ 42) impinging on the elastic and rigid substrate was analyzed, such as spreading, retraction, lift-off, the secondary droplet, and contact time with a high-speed camera. FINDINGS: The elastic substrate significantly affected the retraction and lift-off of the droplet-that is, an earlier and more efficient morphological rearrangement of the droplet-reducing the contact time by up to 8.3% (17 < We ≤ 32). The combination of elasticity and hydrophobicity is a new bioinspired strategy that provides an insight into one of the mechanisms by which birds flying in the rain cannot be bedewed while guiding the design of water-repellent surfaces.


Assuntos
Aves/fisiologia , Tecido Elástico/fisiologia , Plumas/química , Chuva , Água/química , Molhabilidade , Animais , Plumas/fisiologia , Propriedades de Superfície
7.
Br Poult Sci ; 60(2): 105-108, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30595026

RESUMO

1. The c/c alleles are responsible for the white plumage colour of ducks; however, the gene corresponding to this locus is still unclear. In order to identify the locus-related candidate gene associated with duck's plumage colour pattern, it was necessary to analyse the whole genome resequencing data. 2. A total of 929,465 SNPs in chromosome 13 and 1,688 SNPs in the region of the Microphthalmia-Associated Transcription Factor (MITF) gene were identified from whole genome resequencing data analysis. After construction of an FST plot from chromosome 13, MITF was highlighted as a candidate gene, possessing the highest FST value (0.811) on chromosome 13. 3. Six novel SNPs were discovered, located in the intronic region of the MITF gene. F2 progeny of Kaiya × Liancheng ducks (N = 1,061) were selected for genotyping by the Restriction Fragment Length Polymorphism (RFLP) technique. Association analysis using Haploview software was used for validation of the results. 4. Association results between SNPs and phenotypes showed significant association with corresponding phenotypes. All the significantly associated SNPs were located in the identified candidate gene. 5. The identified candidate gene provided novel information which is important in marker-assisted selection and breeding of duck and for the investigation of the C locus recessive white genetic mechanisms underlying plumage colour pattern.


Assuntos
Proteínas Aviárias/genética , Patos/fisiologia , Plumas/fisiologia , Genes Recessivos , Fator de Transcrição Associado à Microftalmia/genética , Pigmentação/genética , Animais , Proteínas Aviárias/metabolismo , China , Cor , Patos/genética , Fator de Transcrição Associado à Microftalmia/metabolismo , Sequenciamento Completo do Genoma/veterinária
8.
PLoS One ; 14(1): e0209737, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30608973

RESUMO

Feather quality is of critical importance to long-distance migratory birds. Here, we report a series of analyses of a unique data set encompassing known-age individuals of the long-distance migratory Sand Martin (Riparia riparia). Sampling over 17 years along the Tisza River, eastern Hungary, has resulted in the recapture of numerous individuals enabling longitudinal and cross-sectional investigation of the role of adaptation to variable environmental conditions on feather morphology. We show that older individuals tend to possess better quality feathers, measured using bending stiffness, feather length and thickness as proxies. Bending stiffness and feather thickness do not change with individual age, in contrast with increases in feather length and declines in daily feather growth versus age of individual alongside moult duration. Individuals who live to older ages tend to have similar, or higher, feather growth rates and better feather quality than individuals captured at younger ages. Thus, on the basis of strong selection against individuals with slow feather growth, as seen in other species of swallows and martins, which causes a delay in moult completion, the results of this analysis highlight the potential cost of producing better quality feathers when this depends on moult duration. Feather length also does change during the lifetime of the individual and thus enabled us to further investigate influence of individual and environmental conditions during the moult. The results of this analysis provide important insights on the adaptive significance of these traits, and the potential use of physical characteristics in unravelling the reasons why long distance migratory bird populations are in global decline.


Assuntos
Plumas/crescimento & desenvolvimento , Plumas/fisiologia , Fatores Etários , Migração Animal/fisiologia , Animais , Aves , Estudos Transversais , Plumas/metabolismo , Hungria , Estudos Longitudinais , Muda , Passeriformes/crescimento & desenvolvimento , Passeriformes/fisiologia , Reprodução
9.
Development ; 145(17)2018 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-30111656

RESUMO

Sensing a global directional cue to orient cell growth is crucial in tissue morphogenesis. An anterior-posterior gradient of Wnt signaling controls the helical growth of feather branches (barbs), and thus the formation of bilateral feathers. However, it remains unclear how the keratinocytes sense this gradient and orient barb growth. Here, we show that in chicken, owing to feather branching, the global Wnt gradient is subdivided into periodic barbs. Within each barb, the anterior barbule plate cells tilt before the posterior cells. The core planar cell polarity gene Prickle1 is involved, as knockdown of its expression resulted in no cell shape change and no barb tilting. Furthermore, perturbation of the Wnt gradient leads to diffusive Prickle1 expression and loss of barb orientation. Finally, the asymmetric distribution of Wnt6/Fzd10 is coordinated by the apical-basal polarity of the barbule plate keratinocytes, which is in turn regulated by the Par3/aPKC machinery. Our data elucidate a new mechanism through which the global Wnt signaling gradient is interpreted locally to construct complex spatial forms.


Assuntos
Polaridade Celular/genética , Plumas/embriologia , Plumas/fisiologia , Proteínas com Domínio LIM/genética , Via de Sinalização Wnt/genética , Animais , Forma Celular/genética , Galinhas , Queratinócitos/citologia , Masculino , Proteínas de Membrana/metabolismo , Morfogênese/genética , Interferência de RNA , RNA Interferente Pequeno/genética
10.
Gigascience ; 7(5)2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29762663

RESUMO

Background: Japanese quail (Coturnix japonica), a recently domesticated poultry species, is important not only as an agricultural product, but also as a model bird species for genetic research. However, most of the biological questions concerning genomics, phylogenetics, and genetics of some important economic traits have not been answered. It is thus necessary to complete a high-quality genome sequence as well as a series of comparative genomics, evolution, and functional studies. Results: Here, we present a quail genome assembly spanning 1.04 Gb with 86.63% of sequences anchored to 30 chromosomes (28 autosomes and 2 sex chromosomes Z/W). Our genomic data have resolved the long-term debate of phylogeny among Perdicinae (Japanese quail), Meleagridinae (turkey), and Phasianinae (chicken). Comparative genomics and functional genomic data found that four candidate genes involved in early maturation had experienced positive selection, and one of them encodes follicle stimulating hormone beta (FSHß), which is correlated with different FSHß levels in quail and chicken. We re-sequenced 31 quails (10 wild, 11 egg-type, and 10 meat-type) and identified 18 and 26 candidate selective sweep regions in the egg-type and meat-type lines, respectively. That only one of them is shared between egg-type and meat-type lines suggests that they were subject to an independent selection. We also detected a haplotype on chromosome Z, which was closely linked with maroon/yellow plumage in quail using population resequencing and a genome-wide association study. This haplotype block will be useful for quail breeding programs. Conclusions: This study provided a high-quality quail reference genome, identified quail-specific genes, and resolved quail phylogeny. We have identified genes related to quail early maturation and a marker for plumage color, which is significant for quail breeding. These results will facilitate biological discovery in quails and help us elucidate the evolutionary processes within the Phasianidae family.


Assuntos
Genética Populacional , Genômica/métodos , Codorniz/genética , Característica Quantitativa Herdável , Sequência de Aminoácidos , Animais , Evolução Biológica , Cromossomos/genética , Plumas/fisiologia , Genoma , Estudo de Associação Genômica Ampla , Sistema Imunitário/metabolismo , Família Multigênica , Nucleotídeos/genética , Filogenia , Pigmentação/genética , Polimorfismo de Nucleotídeo Único/genética , Seleção Genética , Maturidade Sexual/genética , Especificidade da Espécie
11.
Mar Pollut Bull ; 126: 137-140, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29421080

RESUMO

Aquatic pollution events can be detrimental to the survival of wildlife, particularly birds. To decontaminate affected birds, large quantities of fresh water are required. A recent study using seabird feathers, demonstrated that seawater wash/rinse can effectively remove oil from feathers. However to determine whether seawater was effective for live birds, we used 36 mallard ducks to replicate the oiled feather wash/rinse study. We investigated the time and volume of water used, bird water-proofing scores after daily swims and a barbule amalgamation index (BAI), for feathers collected at stages throughout the process. Results indicate that for oiled mallard ducks, the use of seawater for decontamination wash/rinse was effective. Seawater wash however, took longer and used a greater quantity of water. Time to birds being waterproof, was not significantly different between groups. The use of seawater has worldwide application for oiled wildlife response activities particularly in areas where freshwater supplies are limited.


Assuntos
Plumas/fisiologia , Poluição por Petróleo , Trabalho de Resgate/métodos , Água do Mar , Animais , Animais Selvagens , Aves , Patos , Petróleo
12.
Naturwissenschaften ; 105(1-2): 17, 2018 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-29404701

RESUMO

Carry-over effects refer to processes that occur in one season and influence fitness in the following. In birds, two costly activities, namely reproduction and moult, are restricted to a small time window, and sometimes overlap. Thus, colour in newly moulted feathers is likely to be affected by the costs of reproduction. Using models of bird vision we investigated male colour change in a free-living population of blue tits (Cyanistes caeruleus) in three sampling occasions: spring 1, winter and spring 2. We related crown, tail, breast and cheek feather colouration after the moult (winter) to the intensity of infections by blood parasites during reproduction (spring 1). In the following spring (spring 2), we explored mating patterns with respect to changes in feather colour (springs 1 vs. 2). Males that were less intensely infected by the malaria parasite Plasmodium while breeding showed purer white cheek feathers in winter, which may indicate higher feather quality. Increased brightness in the white cheek was associated with better body condition during reproduction. In the following season, males with brighter cheeks paired with females that had noticeably brighter cheek patches compared to the male's previous mate. These results suggest that the conditions experienced during reproduction are likely to affect moult and thus feather colouration, at least in the white patch. High quality individuals may allocate resources efficiently during reproduction increasing future reproductive success through variation in mating patterns. Carry-over effects from reproduction might extend not only to the non-breeding phase, but also to the following breeding season.


Assuntos
Doenças das Aves/fisiopatologia , Plumas/fisiologia , Malária/veterinária , Passeriformes/fisiologia , Passeriformes/parasitologia , Pigmentação/fisiologia , Animais , Cruzamento , Feminino , Malária/fisiopatologia , Masculino , Passeriformes/anatomia & histologia , Plasmodium/fisiologia , Comportamento Sexual Animal/fisiologia
13.
Poult Sci ; 97(5): 1852-1860, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29462461

RESUMO

Soups and broths are popular in the world due to their nutrition and flavor, and flavor compounds tend to be bound by the proteins in the soups and broth, influencing the flavor perception. Thus, identification of the major proteins in meat-based broth may present a basis for understanding protein adsorption of flavor compounds. The present study aimed to identify the major proteins in traditional Chinese chicken broth and to describe the structural changes of proteins during stewing (1, 2, or 3 h). As stewing time increased, protein content in the broth significantly increased. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) indicated that the macro-molecule proteins (>10 kDa) in the broth were mainly gelatin and actin and that the micro-molecule proteins fractions (<10 kDa) increased substantially. The gelatin had an ordered structure even after 3 h of stewing, as seen by circular dichroism (CD) spectroscopy. The presence of reactive sulfhydryl groups increased remarkably with stewing time. The surface hydrophobicity of the proteins significantly increased within 2 h then deceased slightly after 3 h. The intermolecular crosslinks, as indicated by dispersion index, increased remarkably, consistent with the result of atomic force microscopy (AFM), which together suggested that protein aggregation increased during stewing. These findings suggested that gelatin was the structural protein in the broth system and that intermolecular crosslinks functioned to maintain the broth system.


Assuntos
Proteínas Aviárias/análise , Galinhas , Culinária , Produtos da Carne/análise , Animais , Proteínas Aviárias/química , Galinhas/fisiologia , Cor , Eletroforese em Gel de Poliacrilamida , Plumas/fisiologia
14.
Poult Sci ; 97(5): 1484-1502, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29462494

RESUMO

This 2 × 2 factorial experiment aimed to investigate the effects of stimulating foraging behavior from wk 6 and imposed stress at wk 16 on the development of severe feather pecking (SFP) in chickens reared for free-range egg production. Non-beak-trimmed ISA Brown chicks were purchased at one day old and floor-reared on wood shavings. From wk 6, straw was provided daily in dispensers (Forage vs. No forage) to stimulate foraging. At wk 15, there were 16 pens of 50 pullets. "Stressors" were applied to half the pens in wk 16 via combined transport, relocation, and mixing (TRM) of pullets, simulating activities around transfer from the rearing to egg-laying farm (TRM vs. Not TRM). Range access was permitted from wk 21. Behavior, plumage damage (PD), growth, egg production, feed use, injuries, and mortalities were recorded, along with litter moisture and pH. In wk 26, an SFP outbreak commenced. By wk 34, PD was worse in south- than north-aspect pens (P < 0.001). Further, PD was more affected by side of the shed than the experimental treatments. In wk 30, an outbreak of injurious pecking (IP) commenced in the 4 TRM-treatment pens on the south side, with IP deaths almost 3 times more common in the Forage+TRM than No forage+TRM treatment. We suggest factors associated with a 13-day rainfall event that occurred in late winter predisposed the flock to SFP. While multiple factors such as winter cold, muddy ranges, damp floor litter with elevated pH, among others coincided, hens were clearly more impacted in south- than north-aspect pens. Once initiated, SFP possibly spread via social learning, and by wk 40, ∼98% of hens had PD. Interestingly, the IP outbreak was related to a combination of factors (stressors?), such as being housed in colder, damper south-aspect pens (note: southern hemisphere), having added Forage, and TRM. These unexpected relationships could help direct future research to identify the specific factors involved in the causation of SFP and IP/cannibalism outbreaks.


Assuntos
Agressão , Canibalismo , Galinhas/fisiologia , Plumas/fisiologia , Comportamento Alimentar , Estresse Fisiológico , Animais , Austrália , Feminino , Abrigo para Animais
15.
Nat Commun ; 9(1): 1, 2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29317637

RESUMO

Many studies have shown how pigments and internal nanostructures generate color in nature. External surface structures can also influence appearance, such as by causing multiple scattering of light (structural absorption) to produce a velvety, super black appearance. Here we show that feathers from five species of birds of paradise (Aves: Paradisaeidae) structurally absorb incident light to produce extremely low-reflectance, super black plumages. Directional reflectance of these feathers (0.05-0.31%) approaches that of man-made ultra-absorbent materials. SEM, nano-CT, and ray-tracing simulations show that super black feathers have titled arrays of highly modified barbules, which cause more multiple scattering, resulting in more structural absorption, than normal black feathers. Super black feathers have an extreme directional reflectance bias and appear darkest when viewed from the distal direction. We hypothesize that structurally absorbing, super black plumage evolved through sensory bias to enhance the perceived brilliance of adjacent color patches during courtship display.


Assuntos
Plumas/ultraestrutura , Luz , Passeriformes/fisiologia , Animais , Fenômenos Biofísicos , Simulação por Computador , Plumas/fisiologia , Processamento de Imagem Assistida por Computador , Masculino , Microscopia Eletrônica de Varredura , Especificidade da Espécie , Tomografia Computadorizada por Raios X/métodos
16.
Proc Natl Acad Sci U S A ; 115(2): E218-E225, 2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29279398

RESUMO

Hybrid speciation is rare in vertebrates, and reproductive isolation arising from hybridization is infrequently demonstrated. Here, we present evidence supporting a hybrid-speciation event involving the genetic admixture of the snow-capped (Lepidothrix nattereri) and opal-crowned (Lepidothrix iris) manakins of the Amazon basin, leading to the formation of the hybrid species, the golden-crowned manakin (Lepidothrix vilasboasi). We used a genome-wide SNP dataset together with analysis of admixture, population structure, and coalescent modeling to demonstrate that the golden-crowned manakin is genetically an admixture of these species and does not represent a hybrid zone but instead formed through ancient genetic admixture. We used spectrophotometry to quantify the coloration of the species-specific male crown patches. Crown patches are highly reflective white (snow-capped manakin) or iridescent whitish-blue to pink (opal-crowned manakin) in parental species but are a much less reflective yellow in the hybrid species. The brilliant coloration of the parental species results from nanostructural organization of the keratin matrix feather barbs of the crown. However, using electron microscopy, we demonstrate that the structural organization of this matrix is different in the two parental species and that the hybrid species is intermediate. The intermediate nature of the crown barbs, resulting from past admixture appears to have rendered a duller structural coloration. To compensate for reduced brightness, selection apparently resulted in extensive thickening of the carotenoid-laden barb cortex, producing the yellow crown coloration. The evolution of this unique crown-color signal likely culminated in premating isolation of the hybrid species from both parental species.


Assuntos
Especiação Genética , Hibridização Genética , Passeriformes/genética , Distribuição Animal , Animais , Carotenoides/metabolismo , Plumas/fisiologia , Feminino , Estudo de Associação Genômica Ampla , Queratinas/fisiologia , Masculino , Passeriformes/fisiologia , Polimorfismo de Nucleotídeo Único , Caracteres Sexuais , África do Sul , América do Sul
17.
Poult Sci ; 97(2): 358-367, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29177490

RESUMO

An important indicator of the health and behavior of laying hens is their plumage condition. Various scoring systems are used, and various risk factors for feather damage have been described. Often, a summarized score of different body parts is used to describe the overall condition of the plumage of a bird. However, it has not yet been assessed whether such a whole body plumage score is a suitable outcome variable when analyzing the risk factors for plumage deterioration. Data collected within a German project on farms keeping laying hens in aviaries were analyzed to investigate whether and the extent to which information is lost when summarizing the scores of the separate body parts. Two models were fitted using multiblock redundancy analysis, in which the first model included the whole body score as one outcome variable, while the second model included the scores of the individual body parts as multiple outcome variables. Although basically similar influences could be discovered with both models, the investigation of the individual body parts allowed for consideration of the influences on each body part separately and for the identification of additional influences. Furthermore, ambivalent influences (a factor differently associated with 2 different outcomes) could be detected with this approach, and possible dilutive effects were avoided. We conclude that influences might be underestimated or even missed when modeling their explanatory power for an overall score only. Therefore, multivariate methods that allow for the consideration of individual body parts are an interesting option when investigating influences on plumage condition.


Assuntos
Criação de Animais Domésticos/métodos , Galinhas/fisiologia , Plumas/fisiologia , Reprodução , Animais , Feminino , Alemanha , Modelos Teóricos
18.
Animal ; 12(3): 585-596, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28780926

RESUMO

The purpose of the present study was to evaluate locomotor strategies during development in domestic chickens (Gallus gallus domesticus); we were motivated, in part, by current efforts to improve the design of housing systems for laying hens which aim to reduce injury and over-exertion. Using four strains of laying hens (Lohmann Brown, Lohmann LSL lite, Dekalb White and Hyline Brown) throughout this longitudinal study, we investigated their locomotor style and climbing capacity in relation to the degree (0 to 70°) of incline, age (2 to 36 weeks) and the surface substrate (sandpaper or wire grid). Chicks and adult fowl performed only walking behavior to climb inclines ⩽40° and performed a combination of wing-assisted incline running (WAIR) or aerial ascent on steeper inclines. Fewer birds used their wings to aid their hind limbs when climbing 50° inclines on wire grid surface compared with sandpaper. The steepness of angle achieved during WAIR and the tendency to fly instead of using WAIR increased with increasing age and experience. White-feathered strains performed more wing-associated locomotor behavior compared with brown-feathered strains. A subset of birds was never able to climb incline angles >40° even when using WAIR. Therefore, we suggest that inclines of up to 40° should be provided for hens in three-dimensional housing systems, which are easily negotiated (without wing use) by chicks and adult fowl.


Assuntos
Galinhas/fisiologia , Animais , Fenômenos Biomecânicos , Plumas/fisiologia , Feminino , Voo Animal , Membro Posterior/fisiologia , Abrigo para Animais , Locomoção , Estudos Longitudinais , Corrida/fisiologia , Asas de Animais/fisiologia
19.
PLoS One ; 12(10): e0187282, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29088288

RESUMO

Wing morphology strongly affects flight performance which may consequently decline during feather moult due to the creation of feather gaps in the wing. Hence, the size and shape of moult-related wing gap may directly affect flight capacity. Here I examined the rare divergent primary moult sequence compared to the more common descendant moult sequence. In the divergent moult, the focus of primary moult is shifted from P1 (primary feather numbered descendantly) to another primary between P2 and P5, and then primaries are moulted in two concurrent waves, one descendant and the other ascendant. The result of this rare moult sequence is the splitting of the wing gap to two smaller gaps. Using a large moult database including 6,763 individuals of 32 Western Palaearctic passerine species, I found evidence of divergent moult only among 27 individuals of 12 species. I examined the speed of wing-feather moult for each individual that moulted divergently compared to a control group of individuals at the same moult stage which moulted following the common descending sequence. The results indicate that the sequence of primary moult and moult speed are correlated. Individuals which moulted divergently moulted their primaries with higher moult speed than descendant moulters. The applicability of this study is weakened by the dearth of moult data, thus making it difficult to draw conclusions for a large range of species. Ornithologists and bird ringers are therefore encouraged to collect more basic moult data during their field study.


Assuntos
Muda/fisiologia , Passeriformes/fisiologia , Asas de Animais/fisiologia , Animais , Plumas/anatomia & histologia , Plumas/fisiologia , Voo Animal/fisiologia , Israel , Passeriformes/anatomia & histologia , Aves Canoras/anatomia & histologia , Aves Canoras/fisiologia , Fatores de Tempo , Asas de Animais/anatomia & histologia
20.
Curr Biol ; 27(22): 3520-3525.e4, 2017 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-29129533

RESUMO

In his book on sexual selection, Darwin [1] devoted equal space to non-vocal and vocal communication in birds. Since then, vocal communication has become a model for studies of neurobiology, learning, communication, evolution, and conservation [2, 3]. In contrast, non-vocal "instrumental music," as Darwin called it, has only recently become subject to sustained inquiry [4, 5]. In particular, outstanding work reveals how feathers, often highly modified, produce distinctive sounds [6-9], and suggests that these sounds have evolved at least 70 times, in many orders [10]. It remains to be shown, however, that such sounds are signals used in communication. Here we show that crested pigeons (Ochyphaps lophotes) signal alarm with specially modified wing feathers. We used video and feather-removal experiments to demonstrate that the highly modified 8th primary wing feather (P8) produces a distinct note during each downstroke. The sound changes with wingbeat frequency, so that birds fleeing danger produce wing sounds with a higher tempo. Critically, a playback experiment revealed that only if P8 is present does the sound of escape flight signal danger. Our results therefore indicate, nearly 150 years after Darwin's book, that modified feathers can be used for non-vocal communication, and they reveal an intrinsically reliable alarm signal.


Assuntos
Comunicação Animal , Columbidae/fisiologia , Plumas/fisiologia , Animais , Voo Animal/fisiologia , Som , Vibração , Asas de Animais/fisiologia
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