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Alfonso Marzal - One of the best experts on this subject based on the ideXlab platform.
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Exploring the adjustment to parasite pressure hypothesis: differences in Uropygial Gland volume and haemosporidian infection in palearctic and neotropical birds
Current Zoology, 2020Co-Authors: Sergio Magallanes, Florentino De Lope, Anders Pape Moller, Charlene Luján-vega, Esteban Fong, Daniel Vecco, Wendy Flores-saavedra, Luz García-longoriaa, José Iannacone, Alfonso MarzalAbstract:Abstract Parasites are globally widespread pathogenic organisms, which impose important selective forces upon their hosts. Thus, in accordance with the Adjustment to parasite pressure hypothesis, it is expected that defenses among hosts vary relative to the selective pressure imposed by parasites. According to the latitudinal gradient in diversity, species richness and abundance of parasites peak near the equator. The Uropygial Gland is an important defensive exocrine Gland against pathogens in birds. Size of the Uropygial Gland has been proposed to vary among species of birds because of divergent selection by pathogens on their hosts. Therefore, we should expect that bird species from the tropics should have relatively larger Uropygial Glands for their body size than species from higher latitudes. However, this hypothesis has not yet been explored. Here, we analyze the size of the Uropygial Gland of 1719 individual birds belonging to 36 bird species from 3 Neotropical (Peru) and 3 temperate areas (Spain). Relative Uropygial Gland volume was 12.52% larger in bird species from the tropics than from temperate areas. This finding is consistent with the relative size of this defensive organ being driven by selective pressures imposed by parasites. We also explored the potential role of this Gland as a means of avoiding haemosporidian infection, showing that species with large Uropygial Glands for their body size tend to have lower mean prevalence of haemosporidian infection, regardless of their geographical origin. This result provides additional support for the assumption that secretions from the Uropygial Gland reduce the likelihood of becoming infected with haemosporidians.
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Reproductive success related to Uropygial Gland volume varies with abundance of conspecifics in barn swallows Hirundo rustica
Behavioral Ecology and Sociobiology, 2018Co-Authors: Sergio Magallanes, Cosme López-calderón, Florentino De Lope, Javier Balbontín, Anders P. Møller, Alfonso MarzalAbstract:Pathogens have negative effects on the fitness of their hosts, reducing survival and/or decreasing their reproductive success. To cope with pathogen challenge, animals have developed a variety of defensive traits to evade parasite infection and minimize their detrimental effects. Uropygial Gland secretion has been proposed to have antimicrobial and antifungal properties, which may potentially influence bird fitness. However, whether Uropygial Gland secretion may affect the breeding success of birds remains unknown. Here, we explore whether the relationship between Uropygial Gland volume and reproductive success could be determined by the abundance of conspecific barn swallows ( Hirundo rustica ), a small colonial migratory hirundine. Because a larger number of swallows nesting within the same building may boost abundance and transmission of pathogens, we predicted that the anti-pathogen properties of Uropygial Gland secretion may enhance bird reproductive success in environments with high density of conspecifics. We showed that barn swallows with larger Uropygial Glands had higher breeding success (greater total number of fledglings reared) when living in environments with higher abundance of conspecifics. In contrast, barn swallows with larger Uropygial Glands had lower reproductive success when breeding in environments with lower abundance of conspecifics. Furthermore, we found that the same individuals did not modify Uropygial Glands in response to different pathogen pressure experienced across consecutive years. These outcomes suggest that benefits of Uropygial secretion are host density dependent, thus consistent with this being a heritable trait that has evolved as a consequence of divergent selection imposed by pathogens. Significance statement To face pathogen challenges, animals have evolved a broad range of barriers and defense mechanisms to avoid parasite infection and/or to minimize negative effects. Uropygial Gland secretion has been proposed to have antimicrobial and antifungal properties, but also act as a defensive mechanism against malaria infection. However, whether Uropygial Gland secretions may affect the reproductive success of birds remains poorly studied. In this study, we explore, for the first time, whether the relationship between Uropygial Gland volume and reproductive success could be determined by the abundance of conspecifics. We found that barn swallows with larger Uropygial Glands had higher breeding success when living in environments with higher abundance of conspecifics. Because a larger number of swallows nesting within the same building may boost abundance and transmission of pathogens, this novel outcome is consistent with a heritable trait that has evolved as a consequence of divergent selection imposed by pathogens.
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reproductive success related to Uropygial Gland volume varies with abundance of conspecifics in barn swallows hirundo rustica
Behavioral Ecology and Sociobiology, 2018Co-Authors: Sergio Magallanes, Florentino De Lope, Anders Pape Moller, Javier Balbontín, Cosme Lopezcalderon, Alfonso MarzalAbstract:Pathogens have negative effects on the fitness of their hosts, reducing survival and/or decreasing their reproductive success. To cope with pathogen challenge, animals have developed a variety of defensive traits to evade parasite infection and minimize their detrimental effects. Uropygial Gland secretion has been proposed to have antimicrobial and antifungal properties, which may potentially influence bird fitness. However, whether Uropygial Gland secretion may affect the breeding success of birds remains unknown. Here, we explore whether the relationship between Uropygial Gland volume and reproductive success could be determined by the abundance of conspecific barn swallows (Hirundo rustica), a small colonial migratory hirundine. Because a larger number of swallows nesting within the same building may boost abundance and transmission of pathogens, we predicted that the anti-pathogen properties of Uropygial Gland secretion may enhance bird reproductive success in environments with high density of conspecifics. We showed that barn swallows with larger Uropygial Glands had higher breeding success (greater total number of fledglings reared) when living in environments with higher abundance of conspecifics. In contrast, barn swallows with larger Uropygial Glands had lower reproductive success when breeding in environments with lower abundance of conspecifics. Furthermore, we found that the same individuals did not modify Uropygial Glands in response to different pathogen pressure experienced across consecutive years. These outcomes suggest that benefits of Uropygial secretion are host density dependent, thus consistent with this being a heritable trait that has evolved as a consequence of divergent selection imposed by pathogens. To face pathogen challenges, animals have evolved a broad range of barriers and defense mechanisms to avoid parasite infection and/or to minimize negative effects. Uropygial Gland secretion has been proposed to have antimicrobial and antifungal properties, but also act as a defensive mechanism against malaria infection. However, whether Uropygial Gland secretions may affect the reproductive success of birds remains poorly studied. In this study, we explore, for the first time, whether the relationship between Uropygial Gland volume and reproductive success could be determined by the abundance of conspecifics. We found that barn swallows with larger Uropygial Glands had higher breeding success when living in environments with higher abundance of conspecifics. Because a larger number of swallows nesting within the same building may boost abundance and transmission of pathogens, this novel outcome is consistent with a heritable trait that has evolved as a consequence of divergent selection imposed by pathogens.
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Datos botoa Uropygial Gland
2018Co-Authors: Sergio Magallanes, Luz García-longoria, Cosme López-calderón, Maribel Reviriego, Florentino De Lope, Anders Pape Moller, Alfonso MarzalAbstract:Data from Uropygial Gland volume, malaria infection and survival in house martin
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Uropygial Gland volume and malaria infection are related to survival in migratory house martins
Journal of Avian Biology, 2017Co-Authors: Sergio Magallanes, Luz García-longoria, Cosme López-calderón, Maribel Reviriego, F. De Lope, A. P. Møller, Alfonso MarzalAbstract:Pathogens such as bacteria, fungi and malaria and related haemosporidians provoke negative effects on the fitness of their hosts. Animals have developed a range of defensive mechanisms to resist or eliminate these parasitic infections and their negative fitness costs. The Uropygial Gland secretion has been proposed to act as defensive barrier of skin and plumage in the fight against bacteria and fungi, and may prevent birds from acquiring haemosporidian infections. Thus, the secretion of Uropygial Glands of birds may favour survival of individuals. However, whether Uropygial Gland secretion influence survival remains unknown. Here we explore if the size of the Uropygial Gland and malaria infection influence survival of house martins Delichon urbica. We showed, for the first time, that the volume of the Uropygial Gland positively predicted survival prospects of malaria infected house martins. Malaria infected birds had the lowest probability of survival, with the effect of Gland size on survival prospects depending on infection: infected house martins with larger Uropygial Glands were better able to survive to the next breeding season, while infected birds with small Uropygial Glands were not. These results highlight the importance of Uropygial Gland secretion in the life history of wild birds.
Diego Montalti - One of the best experts on this subject based on the ideXlab platform.
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The Uropygial Gland of the Eared Dove and its evolutionary history within the Columbiformes (Aves)
Journal of Ornithology, 2019Co-Authors: María Cecilia Chiale, Julieta Carril, Diego Montalti, Claudio Gustavo BarbeitoAbstract:The Uropygial (preen) Gland is a holocrine organ unique of Aves. Although several studies have been performed on the Uropygial Gland of different bird species, knowledge about this Gland in Columbiformes is scarce. In order to fill this gap, we analysed in detail the external morphology and the histological and histochemical features of the Uropygial Gland of the Eared Dove (Zenaida auriculata) in a comparative context. The Uropygial Gland of the Eared Dove is characterized by its pear-like shape composed of two lobes, conical and naked papilla, tubule-alveolar adenomers, a large primary storage chamber (a feature also present in other terrestrial avian species), and reticular and elastic fibres in the capsule and connective tissue surrounding the adenomers. The histochemistry showed a positive reaction to periodic acid-Schiff, Alcian Blue 2.5 and several lectins, evidencing the presence of diverse glycoconjugates in this organ. Since the Uropygial Gland may be independently present or absent within Columbiformes, we also used character mapping on a molecular phylogeny to infer the character states of this Gland at ancestral nodes to understand its evolutionary history. The analysis shows that the presence of the Uropygial Gland is the ancestral state for Columbiformes and that its loss occurred more than once independently.
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the Uropygial Gland of the southern caracara caracara plancus falconidae falconinae histological and histochemical aspects
Acta Zoologica, 2017Co-Authors: María Cecilia Chiale, Diego Montalti, Alicia M Flamini, Claudio Gustavo BarbeitoAbstract:The Uropygial Gland of Southern Caracara is composed of two lobes with a conical papilla and 21 tuft feathers. The RGM recorded for this species was 0.057%. The capsule surrounding the Gland and the medial septum is composed of dense connective tissue and has elastic and reticular fibres. The epithelium of the adenomers can be divided into different strata: germinative, intermediate, secretory and degenerative stratum. The adenomers can be divided into three zones; from zone III, adenomers lead to secondary chambers that converge into a primary storage chamber. Histochemical techniques showed that the Uropygial Gland synthesizes different types of mucins and it was also positive to some lectins demonstrating the presence of a variety of glycoconjugates. The RGM in this species is smaller than that found for other Falconidae. These differences may be attributed to a negative allometric relationship. The general histological description is similar to other birds. The histochemistry and lectin histochemistry analysis showed a variety of glycoconjugates as part of the Uropygial Gland. Uropygial secretions have been proposed to have protective functions against bacteria and fungi. The presence of carbohydrate residues is linked to glycoconjugates with antimicrobial functions in many vertebrates associating our results with this species′ habits.
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Histological and histochemical study of the Uropygial Gland of chimango caracara (Milvago chimango vieillot, 1816).
Biotechnic & histochemistry : official publication of the Biological Stain Commission, 2015Co-Authors: María Cecilia Chiale, Diego Montalti, Mirta Alicia Flamini, Patricia Elena Fernández, Eduardo Juan Gimeno, Claudio Gustavo BarbeitoAbstract:The Uropygial Glands of birds are sebaceous organs that contribute to the water-repellent properties of the feather coat. We studied the histological and histochemical characteristics of the Uropygial Gland of chimango caracara using hematoxylin and eosin (H & E), Gomori´s trichrome, orcein, Gomori´s reticulin, periodic acid-Schiff (PAS), Alcian blue (AB) and a variety of lectins. The Gland is composed of two lobes and a papilla with 20 downy feathers. It is surrounded by a capsule of dense connective tissue that contains elastic, reticular and smooth muscle fibers. The papilla is delicate and has two excretory ducts. The Gland mass relative to body mass was 0.143%. Both adenomer cells and their secretions were stained with Sudan IV, PAS and AB, and were positive for numerous lectins that indicated the presence of lipids and carbohydrates. Immunohistochemical techniques to detect PCNA confirmed cell proliferation in the basal stratum of the adenomer cells. The lipids and glycoconjugates secreted by the Uropygial Gland serve numerous functions including protection against microorganisms.
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The relationship between the feather tuft of the Uropygial Gland and terrestrial/aquatic birds
Revista Brasileira de Ornitologia - Brazilian Journal of Ornithology, 2014Co-Authors: María Cecilia Chiale, Diego MontaltiAbstract:The relationship between the feather tuft of the Uropygial Gland and terrestrial/aquatic birds.
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the relationship between the feather tuft of the Uropygial Gland and terrestrial aquatic birds
Revista Brasileira de Ornitologia - Brazilian Journal of Ornithology, 2014Co-Authors: María Cecilia Chiale, Diego MontaltiAbstract:The relationship between the feather tuft of the Uropygial Gland and terrestrial/aquatic birds.
Sergio Magallanes - One of the best experts on this subject based on the ideXlab platform.
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Exploring the adjustment to parasite pressure hypothesis: differences in Uropygial Gland volume and haemosporidian infection in palearctic and neotropical birds
Current Zoology, 2020Co-Authors: Sergio Magallanes, Florentino De Lope, Anders Pape Moller, Charlene Luján-vega, Esteban Fong, Daniel Vecco, Wendy Flores-saavedra, Luz García-longoriaa, José Iannacone, Alfonso MarzalAbstract:Abstract Parasites are globally widespread pathogenic organisms, which impose important selective forces upon their hosts. Thus, in accordance with the Adjustment to parasite pressure hypothesis, it is expected that defenses among hosts vary relative to the selective pressure imposed by parasites. According to the latitudinal gradient in diversity, species richness and abundance of parasites peak near the equator. The Uropygial Gland is an important defensive exocrine Gland against pathogens in birds. Size of the Uropygial Gland has been proposed to vary among species of birds because of divergent selection by pathogens on their hosts. Therefore, we should expect that bird species from the tropics should have relatively larger Uropygial Glands for their body size than species from higher latitudes. However, this hypothesis has not yet been explored. Here, we analyze the size of the Uropygial Gland of 1719 individual birds belonging to 36 bird species from 3 Neotropical (Peru) and 3 temperate areas (Spain). Relative Uropygial Gland volume was 12.52% larger in bird species from the tropics than from temperate areas. This finding is consistent with the relative size of this defensive organ being driven by selective pressures imposed by parasites. We also explored the potential role of this Gland as a means of avoiding haemosporidian infection, showing that species with large Uropygial Glands for their body size tend to have lower mean prevalence of haemosporidian infection, regardless of their geographical origin. This result provides additional support for the assumption that secretions from the Uropygial Gland reduce the likelihood of becoming infected with haemosporidians.
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Reproductive success related to Uropygial Gland volume varies with abundance of conspecifics in barn swallows Hirundo rustica
Behavioral Ecology and Sociobiology, 2018Co-Authors: Sergio Magallanes, Cosme López-calderón, Florentino De Lope, Javier Balbontín, Anders P. Møller, Alfonso MarzalAbstract:Pathogens have negative effects on the fitness of their hosts, reducing survival and/or decreasing their reproductive success. To cope with pathogen challenge, animals have developed a variety of defensive traits to evade parasite infection and minimize their detrimental effects. Uropygial Gland secretion has been proposed to have antimicrobial and antifungal properties, which may potentially influence bird fitness. However, whether Uropygial Gland secretion may affect the breeding success of birds remains unknown. Here, we explore whether the relationship between Uropygial Gland volume and reproductive success could be determined by the abundance of conspecific barn swallows ( Hirundo rustica ), a small colonial migratory hirundine. Because a larger number of swallows nesting within the same building may boost abundance and transmission of pathogens, we predicted that the anti-pathogen properties of Uropygial Gland secretion may enhance bird reproductive success in environments with high density of conspecifics. We showed that barn swallows with larger Uropygial Glands had higher breeding success (greater total number of fledglings reared) when living in environments with higher abundance of conspecifics. In contrast, barn swallows with larger Uropygial Glands had lower reproductive success when breeding in environments with lower abundance of conspecifics. Furthermore, we found that the same individuals did not modify Uropygial Glands in response to different pathogen pressure experienced across consecutive years. These outcomes suggest that benefits of Uropygial secretion are host density dependent, thus consistent with this being a heritable trait that has evolved as a consequence of divergent selection imposed by pathogens. Significance statement To face pathogen challenges, animals have evolved a broad range of barriers and defense mechanisms to avoid parasite infection and/or to minimize negative effects. Uropygial Gland secretion has been proposed to have antimicrobial and antifungal properties, but also act as a defensive mechanism against malaria infection. However, whether Uropygial Gland secretions may affect the reproductive success of birds remains poorly studied. In this study, we explore, for the first time, whether the relationship between Uropygial Gland volume and reproductive success could be determined by the abundance of conspecifics. We found that barn swallows with larger Uropygial Glands had higher breeding success when living in environments with higher abundance of conspecifics. Because a larger number of swallows nesting within the same building may boost abundance and transmission of pathogens, this novel outcome is consistent with a heritable trait that has evolved as a consequence of divergent selection imposed by pathogens.
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reproductive success related to Uropygial Gland volume varies with abundance of conspecifics in barn swallows hirundo rustica
Behavioral Ecology and Sociobiology, 2018Co-Authors: Sergio Magallanes, Florentino De Lope, Anders Pape Moller, Javier Balbontín, Cosme Lopezcalderon, Alfonso MarzalAbstract:Pathogens have negative effects on the fitness of their hosts, reducing survival and/or decreasing their reproductive success. To cope with pathogen challenge, animals have developed a variety of defensive traits to evade parasite infection and minimize their detrimental effects. Uropygial Gland secretion has been proposed to have antimicrobial and antifungal properties, which may potentially influence bird fitness. However, whether Uropygial Gland secretion may affect the breeding success of birds remains unknown. Here, we explore whether the relationship between Uropygial Gland volume and reproductive success could be determined by the abundance of conspecific barn swallows (Hirundo rustica), a small colonial migratory hirundine. Because a larger number of swallows nesting within the same building may boost abundance and transmission of pathogens, we predicted that the anti-pathogen properties of Uropygial Gland secretion may enhance bird reproductive success in environments with high density of conspecifics. We showed that barn swallows with larger Uropygial Glands had higher breeding success (greater total number of fledglings reared) when living in environments with higher abundance of conspecifics. In contrast, barn swallows with larger Uropygial Glands had lower reproductive success when breeding in environments with lower abundance of conspecifics. Furthermore, we found that the same individuals did not modify Uropygial Glands in response to different pathogen pressure experienced across consecutive years. These outcomes suggest that benefits of Uropygial secretion are host density dependent, thus consistent with this being a heritable trait that has evolved as a consequence of divergent selection imposed by pathogens. To face pathogen challenges, animals have evolved a broad range of barriers and defense mechanisms to avoid parasite infection and/or to minimize negative effects. Uropygial Gland secretion has been proposed to have antimicrobial and antifungal properties, but also act as a defensive mechanism against malaria infection. However, whether Uropygial Gland secretions may affect the reproductive success of birds remains poorly studied. In this study, we explore, for the first time, whether the relationship between Uropygial Gland volume and reproductive success could be determined by the abundance of conspecifics. We found that barn swallows with larger Uropygial Glands had higher breeding success when living in environments with higher abundance of conspecifics. Because a larger number of swallows nesting within the same building may boost abundance and transmission of pathogens, this novel outcome is consistent with a heritable trait that has evolved as a consequence of divergent selection imposed by pathogens.
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Datos botoa Uropygial Gland
2018Co-Authors: Sergio Magallanes, Luz García-longoria, Cosme López-calderón, Maribel Reviriego, Florentino De Lope, Anders Pape Moller, Alfonso MarzalAbstract:Data from Uropygial Gland volume, malaria infection and survival in house martin
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Uropygial Gland volume and malaria infection are related to survival in migratory house martins
Journal of Avian Biology, 2017Co-Authors: Sergio Magallanes, Luz García-longoria, Cosme López-calderón, Maribel Reviriego, F. De Lope, A. P. Møller, Alfonso MarzalAbstract:Pathogens such as bacteria, fungi and malaria and related haemosporidians provoke negative effects on the fitness of their hosts. Animals have developed a range of defensive mechanisms to resist or eliminate these parasitic infections and their negative fitness costs. The Uropygial Gland secretion has been proposed to act as defensive barrier of skin and plumage in the fight against bacteria and fungi, and may prevent birds from acquiring haemosporidian infections. Thus, the secretion of Uropygial Glands of birds may favour survival of individuals. However, whether Uropygial Gland secretion influence survival remains unknown. Here we explore if the size of the Uropygial Gland and malaria infection influence survival of house martins Delichon urbica. We showed, for the first time, that the volume of the Uropygial Gland positively predicted survival prospects of malaria infected house martins. Malaria infected birds had the lowest probability of survival, with the effect of Gland size on survival prospects depending on infection: infected house martins with larger Uropygial Glands were better able to survive to the next breeding season, while infected birds with small Uropygial Glands were not. These results highlight the importance of Uropygial Gland secretion in the life history of wild birds.
Ismael Galvan - One of the best experts on this subject based on the ideXlab platform.
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sources of variation in Uropygial Gland size in european birds
Biological Journal of The Linnean Society, 2013Co-Authors: Ismael Galvan, Csongor I Vagasi, Orsolya Vincze, Istvan Kovacs, Peter L PapAbstract:Defence mechanisms against parasites and pathogens are some of the most elaborate biological systems in animals. The oily secretion of the avian Uropygial Gland has been suggested to serve as a chemical defence against feather and eggshell bacteria. Yet, the traits associated with Uropygial Gland oil production are not well understood. We conducted a phylogenetic analysis comprising 132 European bird species aiming to test: (1) whether life-history and ecological traits drive Gland size evolution by potentially promoting microbial infestation and (2) how these traits affects change in the Gland size throughout the annual cycle. We show that the size of the Uropygial Gland is dynamic (i.e. increasing from the nonbreeding to the breeding season, independent of sex). Furthermore, we found that the year-round size of the Gland was similar between sexes and was correlated with different ecological and life-history traits promoting microbial infection throughout the annual cycle. During the breeding season, the total eggshell surface area in a clutch correlated significantly and positively with the Gland size, suggesting the importance of oil in protecting eggs from microbes. Social species exhibited a larger Gland size increase during the breeding season compared to nonsocials; a change that was also predicted by the total eggshell surface area. Aquatic, riparian and non-migratory species had larger Glands than terrestrials and migrants, respectively. The findings of the present study suggest that aquatic environments may promote the production of Gland oil, through either the need of waterproofing the plumage and/or defending it against the intensified feather degradation in these moist conditions. Finally, we found a negative effect of the incubation period on Uropygial Gland size, which may suggest an energetic constraint imposed by other development-connected costly activities. Our results show that the role of the Uropygial Gland dynamically varies during the annual cycle, potentially in response to seasonal variation in parasitic infection risk. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110, 543-563.
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feather mites and birds an interaction mediated by Uropygial Gland size
Journal of Evolutionary Biology, 2008Co-Authors: Ismael Galvan, Francisco Atienzar, Emilio Barba, Jose L Canto, Veronica Cortes, Ruben Piculo, Juan S Monros, Heather C ProctorAbstract:Feather mites (Arachnida: Acari: Astigmata) feed mainly on secretions of the Uropygial Gland of birds. Here, we use analyses corrected for phylogeny and body size to show that there is a positive correlation between the size of this Gland and mite abundance in passerine birds at an interspecific level during the breeding season, suggesting that the Gland mediates interactions between mites and birds. As predicted on the basis of hypothesized waterproofing and antibiotic functions of Uropygial Gland secretions, riparian ⁄ marsh bird species had larger Glands and higher mite loads than birds living in less mesic terrestrial environments. An unexpected pattern was a steeper relationship between mite load and Gland size in migratory birds than in residents. If moderate mite loads are beneficial to a host but high loads detrimental, this could create complex selection regimes in which Gland size influences mite load and vice versa. Mites may exert selective pressures on Gland size of their hosts that has resulted in smaller Glands among migratory bird species, suggesting that smaller Glands may have evolved in these birds to attenuate a possible detrimental effect of feather mites when present in large numbers.
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Feather mite abundance increases with Uropygial Gland size and plumage yellowness in Great Tits Parus major
Ibis, 2006Co-Authors: Ismael Galvan, Juan José SanzAbstract:Plumicolous feather mites are ectosymbiotic organisms that live on bird feathers. Despite their abundance and prevalence among birds, the ecology of the interaction between these organisms and their hosts is poorly known. As feather mites feed on oil that birds spread from their Uropygial Gland, it has been hypothesized, but never tested, that the number of feather mites increases with the size of the Uropygial Gland of their hosts. In this study the number of feather mites is considered with respect to Uropygial Gland size in a breeding population of Great Tits Parus major in order to test this hypothesis. As predicted, the number of feather mites correlated positively with the Uropygial Gland size of their hosts, showing for the first time that Uropygial Gland size can explain the variance in feather mite load among conspecifics. Previous studies relating feather mite load to plumage colour have suggested that feather mites may be parasitic or neutral. To confirm this, the yellowness of breast feathers was also assessed. However, the results ran in the opposite direction to that expected, showing a positive correlation between mite load and plumage yellowness, which suggests that further work is needed to give clear evidence for a specific nature of feather mites. However, Great Tits with higher mite loads had lower hatching and breeding success, which may support the idea that feather mites are parasites, although this effect must be taken with caution because it was only found in males. Age or sex effects were not found on the number of feather mites, and it is proposed that hormonal levels may not be sufficient to explain the variation in feather mite loads. Interestingly, a positive correlation was detected between Uropygial Gland size and plumage brightness, which could be a novel factor to take into account in studies of plumage colour.
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Feather mite abundance increases with Uropygial Gland size and plumage yellowness in Great Tits Parus major
Ibis, 2006Co-Authors: Ismael Galvan, Juan José SanzAbstract:Plumicolous feather mites are ectosymbiotic organisms that live on bird feathers. Despite\ud their abundance and prevalence among birds, the ecology of the interaction between these\ud organisms and their hosts is poorly known. As feather mites feed on oil that birds spread\ud from their Uropygial Gland, it has been hypothesized, but never tested, that the number of\ud feather mites increases with the size of the Uropygial Gland of their hosts. In this study the\ud number of feather mites is considered with respect to Uropygial Gland size in a breeding population\ud of Great Tits\ud Parus major\ud in order to test this hypothesis. As predicted, the number\ud of feather mites correlated positively with the Uropygial Gland size of their hosts, showing\ud for the first time that Uropygial Gland size can explain the variance in feather mite load among\ud conspecifics. Previous studies relating feather mite load to plumage colour have suggested\ud that feather mites may be parasitic or neutral. To confirm this, the yellowness of breast feathers\ud was also assessed. However, the results ran in the opposite direction to that expected,\ud showing a positive correlation between mite load and plumage yellowness, which suggests\ud that further work is needed to give clear evidence for a specific nature of feather mites. However,\ud Great Tits with higher mite loads had lower hatching and breeding success, which may\ud support the idea that feather mites are parasites, although this effect must be taken with\ud caution because it was only found in males. Age or sex effects were not found on the number\ud of feather mites, and it is proposed that hormonal levels may not be sufficient to explain\ud the variation in feather mite loads. Interestingly, a positive correlation was detected between\ud Uropygial Gland size and plumage brightness, which could be a novel factor to take into\ud account in studies of plumage colour.Peer reviewe
Anders Pape Moller - One of the best experts on this subject based on the ideXlab platform.
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Exploring the adjustment to parasite pressure hypothesis: differences in Uropygial Gland volume and haemosporidian infection in palearctic and neotropical birds
Current Zoology, 2020Co-Authors: Sergio Magallanes, Florentino De Lope, Anders Pape Moller, Charlene Luján-vega, Esteban Fong, Daniel Vecco, Wendy Flores-saavedra, Luz García-longoriaa, José Iannacone, Alfonso MarzalAbstract:Abstract Parasites are globally widespread pathogenic organisms, which impose important selective forces upon their hosts. Thus, in accordance with the Adjustment to parasite pressure hypothesis, it is expected that defenses among hosts vary relative to the selective pressure imposed by parasites. According to the latitudinal gradient in diversity, species richness and abundance of parasites peak near the equator. The Uropygial Gland is an important defensive exocrine Gland against pathogens in birds. Size of the Uropygial Gland has been proposed to vary among species of birds because of divergent selection by pathogens on their hosts. Therefore, we should expect that bird species from the tropics should have relatively larger Uropygial Glands for their body size than species from higher latitudes. However, this hypothesis has not yet been explored. Here, we analyze the size of the Uropygial Gland of 1719 individual birds belonging to 36 bird species from 3 Neotropical (Peru) and 3 temperate areas (Spain). Relative Uropygial Gland volume was 12.52% larger in bird species from the tropics than from temperate areas. This finding is consistent with the relative size of this defensive organ being driven by selective pressures imposed by parasites. We also explored the potential role of this Gland as a means of avoiding haemosporidian infection, showing that species with large Uropygial Glands for their body size tend to have lower mean prevalence of haemosporidian infection, regardless of their geographical origin. This result provides additional support for the assumption that secretions from the Uropygial Gland reduce the likelihood of becoming infected with haemosporidians.
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Function of the Uropygial Gland in eiders (Somateria mollissima)
Avian Research, 2019Co-Authors: Anders Pape Moller, Karsten LaursenAbstract:The Uropygial Gland is an exocrine Gland located above the tail of birds that produces a diverse range of biochemicals. It has been hypothesized to be involved in chemical protection, water-proofing and maintenance of plumage brightness. Although these not necessarily mutually exclusive functions have received some empirical support, there has been little empirical research on the function of water-proofing. Here we analyzed data for 229 individual eiders (Somateria mollissima) collected by Danish hunters during 2016‒2018. The Eider is a sea-duck that spends almost its entire life in sea water emphasizing water-proofing of the plumage. The size of the Uropygial Gland increased with body mass in males, but not in females, and it increased with age. The size of the Uropygial Gland decreased during winter. Eiders with small Uropygial Glands grew their feathers at a fast rate. Eiders with large wing areas had large Uropygial Glands. These findings are consistent with large Uropygial Glands playing a role in water-proofing during molt and foraging, but also that Uropygial Glands may play a role in chemical defense.
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reproductive success related to Uropygial Gland volume varies with abundance of conspecifics in barn swallows hirundo rustica
Behavioral Ecology and Sociobiology, 2018Co-Authors: Sergio Magallanes, Florentino De Lope, Anders Pape Moller, Javier Balbontín, Cosme Lopezcalderon, Alfonso MarzalAbstract:Pathogens have negative effects on the fitness of their hosts, reducing survival and/or decreasing their reproductive success. To cope with pathogen challenge, animals have developed a variety of defensive traits to evade parasite infection and minimize their detrimental effects. Uropygial Gland secretion has been proposed to have antimicrobial and antifungal properties, which may potentially influence bird fitness. However, whether Uropygial Gland secretion may affect the breeding success of birds remains unknown. Here, we explore whether the relationship between Uropygial Gland volume and reproductive success could be determined by the abundance of conspecific barn swallows (Hirundo rustica), a small colonial migratory hirundine. Because a larger number of swallows nesting within the same building may boost abundance and transmission of pathogens, we predicted that the anti-pathogen properties of Uropygial Gland secretion may enhance bird reproductive success in environments with high density of conspecifics. We showed that barn swallows with larger Uropygial Glands had higher breeding success (greater total number of fledglings reared) when living in environments with higher abundance of conspecifics. In contrast, barn swallows with larger Uropygial Glands had lower reproductive success when breeding in environments with lower abundance of conspecifics. Furthermore, we found that the same individuals did not modify Uropygial Glands in response to different pathogen pressure experienced across consecutive years. These outcomes suggest that benefits of Uropygial secretion are host density dependent, thus consistent with this being a heritable trait that has evolved as a consequence of divergent selection imposed by pathogens. To face pathogen challenges, animals have evolved a broad range of barriers and defense mechanisms to avoid parasite infection and/or to minimize negative effects. Uropygial Gland secretion has been proposed to have antimicrobial and antifungal properties, but also act as a defensive mechanism against malaria infection. However, whether Uropygial Gland secretions may affect the reproductive success of birds remains poorly studied. In this study, we explore, for the first time, whether the relationship between Uropygial Gland volume and reproductive success could be determined by the abundance of conspecifics. We found that barn swallows with larger Uropygial Glands had higher breeding success when living in environments with higher abundance of conspecifics. Because a larger number of swallows nesting within the same building may boost abundance and transmission of pathogens, this novel outcome is consistent with a heritable trait that has evolved as a consequence of divergent selection imposed by pathogens.
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Plumage brightness and Uropygial Gland secretions in barn swallows
Current zoology, 2018Co-Authors: Anders Pape Moller, Fernando Mateos-gonzalezAbstract:The Uropygial Gland has been hypothesized to play a role in sexual signaling through a "make-up" function derived from the effects of secretions from the Gland on the appearance of the plumage and bare parts of the body. Here we show that plumage brightness of dorsal feathers of individual barn swallows Hirundo rustica was greater in mated than in unmated individuals. In addition, plumage brightness increased with colony size. Furthermore, plumage brightness was positively correlated with the amount of wax in the Uropygial Gland, negatively correlated with time of sampling of Uropygial wax (perhaps because more wax is present early in the morning after an entire night of wax production without any preening), and negatively correlated with the number of chewing lice that degrade the plumage. Experimentally preventing barn swallows from access to the Uropygial Gland reduced plumage brightness, showing a causal link between secretions from the Uropygial Gland and plumage brightness. These findings provide evidence consistent with a role of Uropygial secretions in signaling plumage brightness.
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plumage brightness and Uropygial Gland secretions in barn swallows
Current Zoology, 2018Co-Authors: Anders Pape Moller, Fernando MateosgonzalezAbstract:The Uropygial Gland has been hypothesized to play a role in sexual signaling through a "make-up" function derived from the effects of secretions from the Gland on the appearance of the plumage and ...
