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Wang H, Yang C, Wang J, Xi Y, Qi J, Hu J, Bai L, Li L, Mustafa A, Liu H. Genome-wide association analysis of neck ring traits in NongHua ma male ducks. Br Poult Sci 2023; 64:670-677. [PMID: 37610317 DOI: 10.1080/00071668.2023.2249840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 07/27/2023] [Accepted: 07/31/2023] [Indexed: 08/24/2023]
Abstract
1. Male NongHua ma ducks have more colourful feathers than females, especially considering that the former have a distinctive neck ring that is different from that of females. This ring development might be influenced by sex selection, the environment, genetics and other elements.2. Genome-wide association analysis (GWAS) was used to locate candidate genes that affect the neck ring formation of male ducks to investigate the genetic basis of this phenomenon.3. In this study, the neck ring area and width of 180 male ducks were assessed at ages 80, 90, 100, 110 and 120 d. GWAS was used to identify associated genes. There were 0, 7, 14, 48 and 21 possible candidate genes annotated around the 0, 12, 25, 76 and 40 SNP loci n corresponding regions. A total of 13 candidate genes were identified around 21 SNP sites at the neck ring width of 120 d.4. These significant genes were annotated and GO and KEGG enrichment analyses were performed. All SNPs that exceeded the significance threshold were annotated and preliminarily screened as candidate genes affecting neck ring formation. From analysis of gene function and enriched KEGG pathways, genes such as THSD1, SLC6A4, DGAT2, PRKDC, B3GAT2, ROR1, GRK7, EXTL3, TXNDC12, COL4A2, PRKG1, ACTR3, were considered important candidate marker sites related to the neck ring. This provided a reference starting point for the genetic mechanism underlying duck feather colour.
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Affiliation(s)
- H Wang
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
| | - C Yang
- Sichuan Animal Science Academy, Sichuan Key Laboratory of Animal Genetics and Breeding, Chengdu, China
| | - J Wang
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
| | - Y Xi
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
| | - J Qi
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
| | - J Hu
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
| | - L Bai
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
| | - L Li
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
| | - A Mustafa
- Institute of Animal Nutrition, Key Laboratory for Animal Disease-Resistance Nutrition of China, Ministry of Education, Sichuan Agricultural University, Chengdu, China
| | - H Liu
- Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China
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Robles-Bello SM, Vázquez-López M, Ramírez-Barrera SM, Terrones-Ramírez AK, Hernández-Baños BE. Drivers of phenotypic divergence in a Mesoamerican highland bird. PeerJ 2022; 10:e12901. [PMID: 35198262 PMCID: PMC8860067 DOI: 10.7717/peerj.12901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 01/17/2022] [Indexed: 01/11/2023] Open
Abstract
Animals derive their coloration from a variety of pigments as well as non-pigmentary structural features. One of the most widespread types of pigments are carotenoids, which are used by all invertebrate taxa and most vertebrate orders to generate red, pink, orange and yellow coloration. Despite their widespread use by diverse animal groups, animals obligately obtain carotenoid pigments from diet. Carotenoid-based coloration is therefore modulated by evolutionary and ecological processes that affect the acquisition and deposition of these pigments into tegumentary structures. The Flame-colored Tanager (Piranga bidentata) is a highland songbird in the cardinal family (Cardinalidae) that is distributed from Mexican sierras through Central America up to western Panama. While female plumage throughout its entire range is predominantly yellow, males exhibit a noticeable split in ventral plumage color, which is bright orange on the West slope and the Tres Marias Islands and blood red in Eastern Mexico and Central America. We used Multiple Regression on Matrices (MRM) to evaluate the relative contributions of geographic distance, climate and genetic distance on color divergence and body differences between geographically disjunct populations. We found that differentiation in carotenoid plumage coloration was mainly explained by rainfall differences between disjunct populations, whereas body size differences was best explained by variation in the annual mean temperature and temperature of coldest quarter. These results indicate that climate is a strong driver of phenotypic divergence in Piranga bidentata.
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Affiliation(s)
- Sahid M. Robles-Bello
- Facultad de Ciencias, Biología Evolutiva, Universidad Nacional Autónoma de México, Ciudad de México, CDMX, México,Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Ciudad de México, CDMX, Mexico
| | - Melisa Vázquez-López
- Facultad de Ciencias, Biología Evolutiva, Universidad Nacional Autónoma de México, Ciudad de México, CDMX, México
| | - Sandra M. Ramírez-Barrera
- Facultad de Ciencias, Biología Evolutiva, Universidad Nacional Autónoma de México, Ciudad de México, CDMX, México
| | - Alondra K. Terrones-Ramírez
- Facultad de Ciencias, Biología Evolutiva, Universidad Nacional Autónoma de México, Ciudad de México, CDMX, México
| | - Blanca E. Hernández-Baños
- Facultad de Ciencias, Biología Evolutiva, Universidad Nacional Autónoma de México, Ciudad de México, CDMX, México
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3
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Plaza PI, Blanco G, Wiemeyer G, López-Rull I, Hornero-Méndez D, Donázar JA, Hiraldo F, Lambertucci SA. Plasma carotenoids and immunity in a despotic avian scavenger. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2020; 333:569-578. [PMID: 32649061 DOI: 10.1002/jez.2397] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 06/18/2020] [Indexed: 01/01/2023]
Abstract
Carotenoids are pigmented compounds acquired through diet that have important functions as antioxidants and immune modulators. We studied the association between immunity and circulating carotenoids in Andean condors (Vultur gryphus). We evaluated the relationship between α-, β-, and γ-globulin blood concentrations and different circulating carotenoids in two groups of Andean condors that differ in their mean health status, rehabilitating (suffering different pathologies), and wild individuals (trapped when displaying their physiological behavior). In rehabilitating individuals, α-, β-, and γ-globulin concentrations were higher than in wild individuals. This shows that rehabilitating individuals were developing an immune response associated with the pathologies that they were suffering at the time of sampling. In addition, circulating carotenoids were lower in rehabilitating than in wild individuals. We found negative correlations between α-, β-, and γ-globulins and different circulating carotenoids in rehabilitating individuals, but not in wild condors. Xanthophylls were strongly related to α-, β-, and γ-globulin blood concentrations in rehabilitating, but not in wild condors. Our results suggest that there is a potential relationship between circulating carotenoids and immunity in the Andean condor. Given that this species may display a carotenoid-based pigmentation, our results could suggest that a trade-off between the immune system and external coloration could operate in this species, which may have implications in their access to food resources and mate selection and, thus, in their conservation.
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Affiliation(s)
- Pablo I Plaza
- Grupo de Investigaciones en Biología de la Conservación, Laboratorio Ecotono, INIBIOMA (Universidad Nacional del Comahue-CONICET), San Carlos de Bariloche, Argentina
| | - Guillermo Blanco
- Department of Evolutionary Ecology, Museo Nacional de Ciencias Naturales (CSIC), Madrid, Spain
| | - Guillermo Wiemeyer
- Grupo de Investigaciones en Biología de la Conservación, Laboratorio Ecotono, INIBIOMA (Universidad Nacional del Comahue-CONICET), San Carlos de Bariloche, Argentina.,The Peregrine Fund, Boise, Idaho.,Ecoparque Buenos Aires-Argentina, Buenos Aires, Argentina
| | - Isabel López-Rull
- Departamento Biología y Geología, Física y Química Inorgánica, ESCET, Universidad Rey Juan Carlos, Madrid, Móstoles, Spain
| | - Dámaso Hornero-Méndez
- Department of Food Phytochemistry, Instituto de la Grasa (CSIC), Campus Universidad Pablo de Olavide, Sevilla, Spain
| | - José A Donázar
- Department of Conservation Biology, Estación Biológica de Doñana, CSIC, Sevilla, Spain
| | - Fernando Hiraldo
- Department of Conservation Biology, Estación Biológica de Doñana, CSIC, Sevilla, Spain
| | - Sergio A Lambertucci
- Grupo de Investigaciones en Biología de la Conservación, Laboratorio Ecotono, INIBIOMA (Universidad Nacional del Comahue-CONICET), San Carlos de Bariloche, Argentina
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4
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Strandin T, Babayan SA, Forbes KM. Reviewing the effects of food provisioning on wildlife immunity. Philos Trans R Soc Lond B Biol Sci 2019. [PMID: 29531143 DOI: 10.1098/rstb.2017.0088] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
While urban expansion increasingly encroaches on natural habitats, many wildlife species capitalize on anthropogenic food resources, which have the potential to both positively and negatively influence their responses to infection. Here we examine how food availability and key nutrients have been reported to shape innate and adaptive immunity in wildlife by drawing from field-based studies, as well as captive and food restriction studies with wildlife species. Examples of food provisioning and key nutrients enhancing immune function were seen across the three study type distinctions, as were cases of trace metals and pharmaceuticals impairing the immunity of wildlife species. More generally, food provisioning in field studies tended to increase innate and adaptive responses to certain immune challenges, whereas patterns were less clear in captive studies. Mild food restriction often enhanced, whereas severe food restriction frequently impaired immunity. However, to enable stronger conclusions we stress a need for further research, especially field studies, and highlight the importance of integrating nutritional manipulation, immune challenge, and functional outcomes. Despite current gaps in research on this topic, modern high throughput molecular approaches are increasingly feasible for wildlife studies and offer great opportunities to better understand human influences on wildlife health.This article is part of the theme issue 'Anthropogenic resource subsidies and host-parasite dynamics in wildlife'.
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Affiliation(s)
- Tomas Strandin
- Department of Virology, University of Helsinki, Helsinki 00290, Finland
| | - Simon A Babayan
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, UK.,The Moredun Research Institute, Pentlands Science Park, Penicuik, Midlothian EH26 0PZ, UK
| | - Kristian M Forbes
- Department of Virology, University of Helsinki, Helsinki 00290, Finland .,Center for Infectious Disease Dynamics and Department of Biology, The Pennsylvania State University, University Park, PA 16082, USA
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5
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Weaver RJ, Koch RE, Hill GE. What maintains signal honesty in animal colour displays used in mate choice? Philos Trans R Soc Lond B Biol Sci 2018; 372:rstb.2016.0343. [PMID: 28533460 DOI: 10.1098/rstb.2016.0343] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/29/2017] [Indexed: 12/15/2022] Open
Abstract
Many of the colour displays of animals are proposed to have evolved in response to female mate choice for honest signals of quality, but such honest signalling requires mechanisms to prevent cheating. The most widely accepted and cited mechanisms for ensuring signal honesty are based on the costly signalling hypothesis, which posits that costs associated with ornamentation prevent low-quality males from being highly ornamented. Alternatively, by the index hypothesis, honesty can be achieved via cost-free mechanisms if ornament production is causally linked to core physiological pathways. In this essay, we review how a costly signalling framework has shaped empirical research in mate choice for colourful male ornaments and emphasize that alternative interpretations are plausible under an index signalling framework. We discuss the challenges in both empirically testing and distinguishing between the two hypotheses, noting that they need not be mutually exclusive. Finally, we advocate for a comprehensive approach to studies of colour signals that includes the explicit consideration of cost-free mechanisms for honesty.This article is part of the themed issue 'Animal coloration: production, perception, function and application'.
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Affiliation(s)
- Ryan J Weaver
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
| | - Rebecca E Koch
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
| | - Geoffrey E Hill
- Department of Biological Sciences, Auburn University, Auburn, AL 36849, USA
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6
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Weaver RJ, Wang P, Hill GE, Cobine PA. An in vivo test of the biologically relevant roles of carotenoids as antioxidants in animals. J Exp Biol 2018; 221:jeb.183665. [DOI: 10.1242/jeb.183665] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 06/19/2018] [Indexed: 11/20/2022]
Abstract
Carotenoids are well known for their contribution to the vibrant coloration of many animals and have been hypothesized to be important antioxidants. Surprisingly few examples of carotenoids acting as biologically relevant antioxidants in vivo exist, in part because experimental designs often employ dosing animals with carotenoids at levels that are rarely observed in nature. Here we use an approach that reduces carotenoid content from wild-type levels to test for the effect of carotenoids as protectants against an oxidative challenge. We used the marine copepod, Tigriopus californicus reared on a carotenoid-free or a carotenoid-restored diet of nutritional yeast and then exposed them to a prooxidant. We found that carotenoid-deficient copepods not only accumulated more damage, but also were more likely to die during an oxidative challenge than carotenoid-restored copepods. We suggest that carotenoid reduction, and not supplementation, better tests the proposed roles of carotenoids in other physiological functions in animals.
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Affiliation(s)
- Ryan J. Weaver
- Department of Biological Sciences, 331 Funchess Hall, Auburn University, Auburn, AL 36849 USA
| | - Philip Wang
- Department of Biological Sciences, 331 Funchess Hall, Auburn University, Auburn, AL 36849 USA
| | - Geoffrey E. Hill
- Department of Biological Sciences, 331 Funchess Hall, Auburn University, Auburn, AL 36849 USA
| | - Paul A. Cobine
- Department of Biological Sciences, 331 Funchess Hall, Auburn University, Auburn, AL 36849 USA
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7
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Foo YZ, Rhodes G, Simmons LW. The carotenoid beta-carotene enhances facial color, attractiveness and perceived health, but not actual health, in humans. Behav Ecol 2017. [DOI: 10.1093/beheco/arw188] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Yong Zhi Foo
- ARC Centre of Excellence in Cognition and its Disorders, School of Psychology, University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009, Australia, and
- Centre for Evolutionary Biology & School of Animal Biology, University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009, Australia
| | - Gillian Rhodes
- ARC Centre of Excellence in Cognition and its Disorders, School of Psychology, University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009, Australia, and
| | - Leigh W. Simmons
- ARC Centre of Excellence in Cognition and its Disorders, School of Psychology, University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009, Australia, and
- Centre for Evolutionary Biology & School of Animal Biology, University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009, Australia
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8
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Henderson AJ, Lasselin J, Lekander M, Olsson MJ, Powis SJ, Axelsson J, Perrett DI. Skin colour changes during experimentally-induced sickness. Brain Behav Immun 2017; 60:312-318. [PMID: 27847284 DOI: 10.1016/j.bbi.2016.11.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 10/29/2016] [Accepted: 11/08/2016] [Indexed: 12/30/2022] Open
Abstract
Skin colour may be an important cue to detect sickness in humans but how skin colour changes with acute sickness is currently unknown. To determine possible colour changes, 22 healthy Caucasian participants were injected twice, once with lipopolysaccharide (LPS, at a dose of 2ng/kg body weight) and once with placebo (saline), in a randomised cross-over design study. Skin colour across 3 arm and 3 face locations was recorded spectrophotometrically over a period of 8h in terms of lightness (L∗), redness (a∗) and yellowness (b∗) in a manner that is consistent with human colour perception. In addition, carotenoid status was assessed as we predicted that a decrease it skin yellowness would reflect a drop in skin carotenoids. We found an early change in skin colouration 1-3h post LPS injection with facial skin becoming lighter and less red whilst arm skin become darker but also less red and less yellow. The LPS injection also caused a drop in plasma carotenoids from 3h onwards. However, the timing of the carotenoid changes was not consistent with the skin colour changes suggesting that other mechanisms, such as a reduction of blood perfusion, oxygenation or composition. This is the first experimental study characterising skin colour associated with acute illness, and shows that changes occur early in the development of the sickness response. Colour changes may serve as a cue to health, prompting actions from others in terms of care-giving or disease avoidance. Specific mechanisms underlying these colour changes require further investigation.
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Affiliation(s)
- Audrey J Henderson
- School of Psychology and Neuroscience, University of St Andrews, Scotland, United Kingdom.
| | - Julie Lasselin
- Division of Psychology, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden; Stress Research Institute, Stockholm University and Karolinska Institutet, Stockholm, Sweden; Institute of Medical Psychology and Behavioral Immunobiology, Universitätsklinikum, Essen, Germany
| | - Mats Lekander
- Division of Psychology, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden; Stress Research Institute, Stockholm University and Karolinska Institutet, Stockholm, Sweden
| | - Mats J Olsson
- Division of Psychology, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Simon J Powis
- School of Medicine, University of St Andrews, Scotland, United Kingdom
| | - John Axelsson
- Division of Psychology, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden; Stress Research Institute, Stockholm University and Karolinska Institutet, Stockholm, Sweden
| | - David I Perrett
- School of Psychology and Neuroscience, University of St Andrews, Scotland, United Kingdom
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9
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Schull Q, Dobson FS, Stier A, Robin JP, Bize P, Viblanc VA. Beak color dynamically signals changes in fasting status and parasite loads in king penguins. Behav Ecol 2016. [DOI: 10.1093/beheco/arw091] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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10
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Karadas F, Erdoğan S, Kor D, Oto G, Uluman M. The Effects of Different Types of Antioxidants (Se, Vitamin E and Carotenoids) in Broiler Diets on the Growth Performance, Skin Pigmentation and Liver and Plasma Antioxidant Concentrations. BRAZILIAN JOURNAL OF POULTRY SCIENCE 2016. [DOI: 10.1590/18069061-2015-0155] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
| | | | - D Kor
- Yüzüncü Yıl University, Turkey
| | - G Oto
- Yüzüncü Yıl University, Turkey
| | - M Uluman
- Kars Directorate of Provincial Food Agriculture and Livestock, Turkey
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11
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Koch RE, Wilson AE, Hill GE. The Importance of Carotenoid Dose in Supplementation Studies with Songbirds. Physiol Biochem Zool 2015; 89:61-71. [PMID: 27082525 DOI: 10.1086/684485] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Carotenoid coloration is the one of the most frequently studied ornamental traits in animals. Many studies of carotenoid coloration test the associations between carotenoid coloration and measures of performance, such as immunocompetence and oxidative state, proceeding from the premise that carotenoids are limited resources. Such studies commonly involve supplementing the diets of captive birds with carotenoids. In many cases, however, the amount of carotenoid administered is poorly justified, and even supposedly carotenoid-limited diets may saturate birds' systems. To quantify the relationships among the amount of carotenoids administered in experiments, levels of circulating carotenoids, and quantities of carotenoids deposited into colored ornaments, we performed a meta-analysis of 15 published studies that supplemented carotenoids to one of seven songbird species. We used allometric scaling equations to estimate the per-gram carotenoid consumption of each study's subjects, and we used meta-regression to evaluate the effects of this carotenoid dose on differences in coloration and plasma carotenoid levels between supplemented and control groups of birds. After accounting for supplementation duration and species, we observed a significant positive correlation between carotenoid intake and response of plasma carotenoid level to supplementation. The presence of supplemental carotenoids also tended to increase the expression of ornamental coloration, but the magnitude of the carotenoid dose did not significantly affect how strongly coloration changed with supplementation. Further, coloration effect sizes had no significant relationship with plasma carotenoid effect sizes. We also found significant heterogeneity in responses among studies and species, and the parameters used to measure color significantly affected response to supplementation. Our results emphasize the importance of performing dosage trials to determine what supplementation levels provide limited versus surplus carotenoids and of measuring the natural level of carotenoid intake by the study species to validate the appropriateness of supplementation levels for a particular study species and experimental design.
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12
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López-Rull I, Hornero-Méndez D, Frías Ó, Blanco G. Age-Related Relationships between Innate Immunity and Plasma Carotenoids in an Obligate Avian Scavenger. PLoS One 2015; 10:e0141759. [PMID: 26544885 PMCID: PMC4636298 DOI: 10.1371/journal.pone.0141759] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 10/12/2015] [Indexed: 11/18/2022] Open
Abstract
Variation in immunity is influenced by allocation trade-offs that are expected to change between age-classes as a result of the different environmental and physiological conditions that individuals encounter over their lifetime. One such trade-off occurs with carotenoids, which must be acquired with food and are involved in a variety of physiological functions. Nonetheless, relationships between immunity and carotenoids in species where these micronutrients are scarce due to diet are poorly studied. Among birds, vultures show the lowest concentrations of plasma carotenoids due to a diet based on carrion. Here, we investigated variations in the relationships between innate immunity (hemagglutination by natural antibodies and hemolysis by complement proteins), pathogen infection and plasma carotenoids in nestling and adult griffon vultures (Gyps fulvus) in the wild. Nestlings showed lower hemolysis, higher total carotenoid concentration and higher pathogen infection than adults. Hemolysis was negatively related to carotenoid concentration only in nestlings. A differential carotenoid allocation to immunity due to the incomplete development of the immune system of nestlings compared with adults is suggested linked to, or regardless of, potential differences in parasite infection, which requires experimental testing. We also found that individuals with more severe pathogen infections showed lower hemagglutination than those with a lower intensity infection irrespective of their age and carotenoid level. These results are consistent with the idea that intraspecific relationships between innate immunity and carotenoids may change across ontogeny, even in species lacking carotenoid-based coloration. Thus, even low concentrations of plasma carotenoids due to a scavenger diet can be essential to the development and activation of the immune system in growing birds.
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Affiliation(s)
- Isabel López-Rull
- Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales-CSIC, Madrid, España
- * E-mail:
| | - Dámaso Hornero-Méndez
- Departamento de Biotecnología de Alimentos, Instituto de la Grasa-CSIC, Sevilla, España
| | - Óscar Frías
- Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales-CSIC, Madrid, España
| | - Guillermo Blanco
- Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales-CSIC, Madrid, España
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13
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Trigo S, Mota PG. What is the value of a yellow patch? Assessing the signalling role of yellow colouration in the European serin. Behav Ecol Sociobiol 2015. [DOI: 10.1007/s00265-014-1860-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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14
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What are carotenoids signaling? Immunostimulatory effects of dietary vitamin E, but not of carotenoids, in Iberian green lizards. Naturwissenschaften 2014; 101:1107-14. [DOI: 10.1007/s00114-014-1250-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 10/01/2014] [Accepted: 10/07/2014] [Indexed: 10/24/2022]
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15
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Do feather-degrading bacteria actually degrade feather colour? No significant effects of plumage microbiome modifications on feather colouration in wild great tits. Naturwissenschaften 2014; 101:929-38. [PMID: 25228345 DOI: 10.1007/s00114-014-1234-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Revised: 07/28/2014] [Accepted: 08/28/2014] [Indexed: 01/26/2023]
Abstract
Parasites are known to exert selective pressures on host life history traits since the energy and nutrients needed to mount an immune response are no longer available to invest in other functions. Bird feathers harbour numerous microorganisms, some of which are able to degrade feather keratin (keratinolytic microorganisms) and affect feather integrity and colouration in vitro. Although named "feather-degrading" microorganisms, experimental evidence for their effects on feathers of free-living birds is still lacking. Here, we tested whether (i) keratinolytic microorganisms can degrade feathers in vivo and thus modify the colour of feathers during the nesting period and (ii) whether feather microorganisms have a long-term effect on the investment in colouration of newly moulted feathers. We designed treatments to either favour or inhibit bacterial growth, thus experimentally modifying plumage bacterial communities, in a wild breeding population of great tits (Parus major). Our analyses revealed no significant effects of the treatments on feather colours. Moreover, we found that differences in bacterial exposure during nesting did not significantly affect the colouration of newly moulted feathers. Our results suggest that significant feather degradation obtained during in vitro studies could have led to an overestimation of the potential of keratinolytic microorganisms to shape feather colouration in free-living birds.
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Figuerola J, López G, Soriguer R. Plasma carotenoid levels in passerines are related to infection by (some) parasites. Front Ecol Evol 2014. [DOI: 10.3389/fevo.2014.00047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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17
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Ibáñez A, Polo-Cavia N, López P, Martín J. Honest sexual signaling in turtles: experimental evidence of a trade-off between immune response and coloration in red-eared sliders Trachemys scripta elegans. Naturwissenschaften 2014; 101:803-11. [PMID: 25091549 DOI: 10.1007/s00114-014-1219-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 07/21/2014] [Accepted: 07/25/2014] [Indexed: 11/30/2022]
Abstract
Sexual signals can be evolutionarily stable if they are honest and condition dependent or costly to the signaler. One possible cost is the existence of a trade-off between maintaining the immune system and the elaboration of ornaments. This hypothesis has been experimentally tested in some groups of animals but not in others such as turtles. We experimentally challenged the immune system of female red-eared sliders Trachemys scripta elegans, with a bacterial antigen (lipopolysaccharide (LPS)) without pathogenic effects to explore whether the immune activation affected visual colorful ornaments of the head. The LPS injection altered the reflectance patterns of color ornaments. In comparison to the control animals, the yellow chin stripes of injected animals exhibited (1) reduced brightness, (2) lower long wavelength (>470 nm) reflectance, and (3) lower values for carotenoid chroma. The postorbital patches of injected individuals also showed reduced very long wavelength (>570 nm) reflectance but did not change in carotenoid chroma. Thus, experimental turtles showed darker and less "yellowish" chin stripes and less "reddish" postorbital patches at the end of the experiment, whereas control turtles did not change their coloration. This is the first experimental evidence supporting the existence of a trade-off between the immune system and the expression of visual ornaments in turtles. We suggest that this trade-off may allow turtles to honestly signal individual quality via characteristics of coloration, which may have an important role in intersexual selection processes.
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Affiliation(s)
- Alejandro Ibáñez
- Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales, C.S.I.C., José Gutiérrez Abascal 2, 28006, Madrid, Spain
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Lumpkin DC, Murphy TG, Tarvin KA. Blood parasite infection differentially relates to carotenoid-based plumage and bill color in the American goldfinch. Ecol Evol 2014; 4:3210-7. [PMID: 25473474 PMCID: PMC4222208 DOI: 10.1002/ece3.1164] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2014] [Revised: 05/27/2014] [Accepted: 06/19/2014] [Indexed: 12/02/2022] Open
Abstract
Male and female American goldfinches (Spinus tristis) express condition-dependent carotenoid-based plumage and bill coloration. Plumage color is relatively static, as pigments incorporated into feathers during the spring molt cannot be mobilized thereafter. In contrast, bill color is dynamic, reflecting changes in condition over short time periods. Previous studies have shown that male and female ornaments, though similar in expression, are differentially related to measures of immunocompetence, suggesting that the relationship between ornamentation and parasite infection may differ between the sexes. In this study, we evaluate the relationship between condition-dependent ornamentation (plumage and bill color) and blood parasite infection in male and female American goldfinches. We captured goldfinches after completion of the pre-alternate molt and prior to the onset of nesting and assessed prevalence of Trypanosoma parasites via blood smears. Plumage color strongly predicted trypanosome infection: Birds with more colorful plumage were less likely to present infections. In contrast, we detected no relationship between infection and bill color, which in other studies has been shown to dynamically reflect current condition. Sex did not affect the relationship between infection status and either ornament. Together, these results suggest that physiological pathways linking carotenoid ornamentation and infection may vary even within a single species.
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Affiliation(s)
| | - Troy G Murphy
- Department of Biology, Trinity University San Antonio, Texas
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Meitern R, Andreson R, Hõrak P. Profile of whole blood gene expression following immune stimulation in a wild passerine. BMC Genomics 2014; 15:533. [PMID: 24972896 PMCID: PMC4092216 DOI: 10.1186/1471-2164-15-533] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 06/24/2014] [Indexed: 12/22/2022] Open
Abstract
Background Immunoecology aims to explain variation among hosts in the strength and efficacy of immunological defences in natural populations. This requires development of biomarkers of the activation of the immune system so that they can be collected non-lethally and sampled from small amounts of easily obtainable tissue. We used transcriptome profiling in wild greenfinches (Carduelis chloris) to detect whole blood transcripts that most profoundly indicate upregulation of antimicrobial defences during acute phase response. The more general aim of this study was to obtain a functional annotation of a substantial portion of the greenfinch transcriptome that would enable to gain access to more specific genomic tools in subsequent studies. The birds received either bacterial lipopolysaccharide or saline injections and RNA-seq transcriptional profiling was performed 12 h after treatment to provide initial functional annotation of the transcriptome and assess whole blood response to immune stimulation. Results A total of 66,084 transcripts were obtained from de novo Trinty assembly, out of which 23,153 could be functionally annotated. Only 1,911 of these were significantly upregulated or downregulated. The manipulation caused marked upregulation of several transcripts related to immune activation. These included avian-specific antimicrobial agents avidin and gallinacin, but also some more general host response genes, such as serum amyloid A protein, lymphocyte antigen 75 and copper-transporting ATPase 1. However, links with avian immunity for most differentially regulated transcripts remained rather hypothetical, as a large set of differentially expressed transcripts lacked functional annotation. Conclusions This appears to be the first large scale transcriptional profiling of immune function in passerine birds. The transcriptomic data obtained suggest novel markers for the assessment of the immunological state of wild passerines. Characterizing the function of those possible novel infection markers would assist future vertebrate genome annotation. The extensive sequence information collected enables to identify possible target and housekeeping genes needed to gain access to more specific genomic tools in future studies. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-533) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Richard Meitern
- Department of Zoology, Institute of Ecology and Earth Sciences, Tartu University, Vanemuise 46, 51014 Tartu, Estonia.
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Hill GE. Cellular respiration: the nexus of stress, condition, and ornamentation. Integr Comp Biol 2014; 54:645-57. [PMID: 24791751 DOI: 10.1093/icb/icu029] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
A fundamental hypothesis for the evolution and maintenance of ornamental traits is that ornaments convey information to choosing females about the quality of prospective mates. A diverse array of ornaments (e.g., colors, morphological features, and behaviors) has been associated with a wide range of measures of individual quality, but decades of study of such indicator traits have failed to produce general mechanisms of honest signaling. Here, I propose that efficiency of cellular respiration, as a product of mitochondrial function, underlies the associations between ornamentation and performance for a broad range of traits across taxa. A large biomedical literature documents the fundamental biochemical links between oxidative phosphorylation (OXPHOS) and the production of reactive oxygen species (ROS), the process of metabolism, the function of the immune system, the synthesis of proteins, and the development and function of the nervous system. The production of virtually all ornaments whose expressions have been demonstrated to be condition-dependent is directly affected by the efficiency of cellular respiration, suggesting that the signaling of respiratory efficiency may be the primary function of such traits. Furthermore, the production of ornaments links to stress-response systems, including particularly the neuroendocrine system, through mitochondrial function, thereby makes ornamental traits effective signals of the capacity to withstand environmental perturbations. The identification of a unifying mechanism of honest signaling holds the potential to connect many heretofore-disparate fields of study related to stress and ornamentation, including neuroendocrinology, respiratory physiology, metabolic physiology, and immunology.
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Affiliation(s)
- Geoffrey E Hill
- Department of Biological Sciences, 331 Funchess Hall, Auburn University, Auburn, AL 36849-5414, USA
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Yang C, Wang J, Fang Y, Sun YH. Is sexual ornamentation an honest signal of male quality in the Chinese grouse (Tetrastes sewerzowi)? PLoS One 2013; 8:e82972. [PMID: 24386132 PMCID: PMC3873284 DOI: 10.1371/journal.pone.0082972] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2013] [Accepted: 11/01/2013] [Indexed: 11/22/2022] Open
Abstract
We examined the variation in sexual ornamentation of male Chinese grouse (Tetrastes sewerzowi) in the Gansu Province, China, seeking to identify factors involved in whether ornament size and brightness are honest signals of male quality. Compared to unmated males, mated males had significantly larger and redder combs and, although they did not have significantly larger territories, they defended them more vigorously. Mated males had significantly higher blood carotenoid and testosterone levels, significantly better body condition, and significantly lower parasite loads than unmated males. Our findings are thus consistent with the hypothesis that comb size and color are honest signals of better male quality in the grouse, mediated through lower parasite loads and/or higher testosterone levels.
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Affiliation(s)
- Chen Yang
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences Institute of Zoology, Chinese Academy of Sciences, Beijing, P. R. of China
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, P. R. of China
| | - Jie Wang
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences Institute of Zoology, Chinese Academy of Sciences, Beijing, P. R. of China
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, P. R. of China
| | - Yun Fang
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences Institute of Zoology, Chinese Academy of Sciences, Beijing, P. R. of China
| | - Yue-Hua Sun
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences Institute of Zoology, Chinese Academy of Sciences, Beijing, P. R. of China
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Lai YT, Kekäläinen J, Kortet R. Male Ornamentation in the European Minnow (Phoxinus phoxinus) Signals Swimming Performance. Ethology 2013. [DOI: 10.1111/eth.12167] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yi-Te Lai
- Department of Biology; University of Eastern Finland; Joensuu Finland
| | - Jukka Kekäläinen
- Department of Biology; University of Eastern Finland; Joensuu Finland
| | - Raine Kortet
- Department of Biology; University of Eastern Finland; Joensuu Finland
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Age-dependent effects of carotenoids on sexual ornaments and reproductive performance of a long-lived seabird. Behav Ecol Sociobiol 2013. [DOI: 10.1007/s00265-013-1628-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Brown AC, McGraw KJ, Clotfelter ED. Dietary Carotenoids Increase Yellow Nonpigment Coloration of Female Convict Cichlids (Amantitlania nigrofasciata). Physiol Biochem Zool 2013; 86:312-22. [DOI: 10.1086/670734] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Female blue tits with brighter yellow chests transfer more carotenoids to their eggs after an immune challenge. Oecologia 2013; 173:387-97. [PMID: 23512200 DOI: 10.1007/s00442-013-2617-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Accepted: 02/05/2013] [Indexed: 10/27/2022]
Abstract
Female ornaments are present in many species, and it is more and more accepted that sexual or social selection may lead to their evolution. By contrast, the information conveyed by female ornaments is less well understood. Here, we investigated the links between female ornaments and maternal effects. In birds, an important maternal effect is the transmission of resources, such as carotenoids, into egg yolk. Carotenoids are pigments with antioxidant and immunomodulatory properties that are crucial for females and developing offspring. In blue tits, we evaluated whether ultraviolet (UV)/blue and yellow feather colouration signals a female's capacity to allocate carotenoids to egg yolk. Because mounting an immune response is costly and trade-offs are more detectable under harsh conditions, we challenged the immune system of females before laying and examined the carotenoid level of their eggs afterward. A positive association between feather carotenoid chroma and egg carotenoid level would be expected if yellow colouration signals basal immunity. Alternatively, if female colouration more generally reflects maternal capacity to invest in reproduction under challenging conditions, then other components of colouration (i.e. yellow brightness and UV/blue colouration) could be linked to maternal capacity to invest in eggs. No association between egg carotenoid levels and UV/blue crown colouration or female yellow chest chroma was found; the latter result suggests that yellow colouration does not signal immune capacity at laying in this species. By contrast, we found that, among females that mounted a detectable response to the vaccine, those with brighter yellow chests transmitted more carotenoids into their eggs. This result suggests yellow brightness signals maternal capacity to invest in reproduction under challenging conditions, and that male blue tits may benefit directly from choosing brighter yellow females.
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Is carotenoid ornamentation linked to the inner mitochondria membrane potential? A hypothesis for the maintenance of signal honesty. Biochimie 2013; 95:436-44. [DOI: 10.1016/j.biochi.2012.10.021] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Accepted: 10/26/2012] [Indexed: 12/16/2022]
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Simons MJP, Cohen AA, Verhulst S. What does carotenoid-dependent coloration tell? Plasma carotenoid level signals immunocompetence and oxidative stress state in birds-A meta-analysis. PLoS One 2012; 7:e43088. [PMID: 22905205 PMCID: PMC3419220 DOI: 10.1371/journal.pone.0043088] [Citation(s) in RCA: 132] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Accepted: 07/16/2012] [Indexed: 11/24/2022] Open
Abstract
Mechanisms maintaining honesty of sexual signals are far from resolved, limiting our understanding of sexual selection and potential important parts of physiology. Carotenoid pigmented visual signals are among the most extensively studied sexual displays, but evidence regarding hypotheses on how carotenoids ensure signal honesty is mixed. Using a phylogenetically controlled meta-analysis of 357 effect sizes across 88 different species of birds, we tested two prominent hypotheses in the field: that carotenoid-dependent coloration signals i) immunocompetence and/or ii) oxidative stress state. Separate meta-analyses were performed for the relationships of trait coloration and circulating carotenoid level with different measures of immunocompetence and oxidative stress state. For immunocompetence we find that carotenoid levels (r = 0.20) and trait color intensity (r = 0.17) are significantly positively related to PHA response. Additionally we find that carotenoids are significantly positively related to antioxidant capacity (r = 0.10), but not significantly related to oxidative damage (r = -0.02). Thus our analyses provide support for both hypotheses, in that at least for some aspects of immunity and oxidative stress state the predicted correlations were found. Furthermore, we tested for differences in effect size between experimental and observational studies; a larger effect in observational studies would indicate that co-variation might not be causal. However, we detected no significant difference, suggesting that the relationships we found are causal. The overall effect sizes we report are modest and we discuss potential factors contributing to this, including differences between species. We suggest complementary mechanisms maintaining honesty rather than the involvement of carotenoids in immune function and oxidative stress and suggest experiments on how to test these.
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Affiliation(s)
- Mirre J P Simons
- Behavioural Biology, University of Groningen, Groningen, The Netherlands.
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Kelly RJ, Murphy TG, Tarvin KA, Burness G. Carotenoid-Based Ornaments of Female and Male American Goldfinches (Spinus tristis) Show Sex-Specific Correlations with Immune Function and Metabolic Rate. Physiol Biochem Zool 2012; 85:348-63. [DOI: 10.1086/666059] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Sternalski A, Mougeot F, Pérez-Rodríguez L, Bretagnolle V. Carotenoid-based coloration, condition, and immune responsiveness in the nestlings of a sexually dimorphic bird of prey. Physiol Biochem Zool 2012; 85:364-75. [PMID: 22705486 DOI: 10.1086/665981] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In many birds, nestlings exhibit brightly colored traits that are pigmented by carotenoids. Carotenoids are diet limited and also serve important health-related physiological functions. The proximate mechanisms behind the expression of these carotenoid-pigmented traits are still poorly known, especially in nestlings with sexual size dimorphism. In these nestlings, intrabrood competition levels and growth strategies likely differ between sexes, and this may in turn influence carotenoid allocation rules. We used dietary carotenoid supplementation to test whether wild marsh harrier (Circus aeruginosus) nestlings were carotenoid limited and whether carotenoid allocation strategies varied between sexes, which differ in their size and growth strategies. When supplemented, nestlings used the supplemental carotenoids to increase their coloration independently of their sex. We showed that the condition dependence of the carotenoid level and the response to an immune challenge (phytohemagglutinin test) differed between sexes, possibly because sexual size dimorphism influences growth strategies and/or intrabrood competition levels and access to different types of food. In this species, which often feeds on mammals, a trade-off likely exists between food quantity (energy) and quality (carotenoid content). Finally, carotenoid-based coloration expressed in marsh harrier nestlings appeared to be indicative of immune responsiveness rather than condition, therefore potentially advertising to parents nestling quality or value rather than nutritional need.
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Affiliation(s)
- Audrey Sternalski
- Instituto de Investigación en Recursos Cinegéticos, Consejo Superior de Investigaciones Cientificas, Universidad de Castilla-La Mancha, Junta de Comunidades de Castilla-La Mancha, Ronda de Toledo s/n, 13005 Ciudad Real, Spain.
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Butler MW, McGraw KJ. Differential effects of early- and late-life access to carotenoids on adult immune function and ornamentation in mallard ducks (Anas platyrhynchos). PLoS One 2012; 7:e38043. [PMID: 22666443 PMCID: PMC3364205 DOI: 10.1371/journal.pone.0038043] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Accepted: 05/01/2012] [Indexed: 11/18/2022] Open
Abstract
Environmental conditions early in life can affect an organism’s phenotype at adulthood, which may be tuned to perform optimally in conditions that mimic those experienced during development (Environmental Matching hypothesis), or may be generally superior when conditions during development were of higher quality (Silver Spoon hypothesis). Here, we tested these hypotheses by examining how diet during development interacted with diet during adulthood to affect adult sexually selected ornamentation and immune function in male mallard ducks (Anas platyrhynchos). Mallards have yellow, carotenoid-pigmented beaks that are used in mate choice, and the degree of beak coloration has been linked to adult immune function. Using a 2×2 factorial experimental design, we reared mallards on diets containing either low or high levels of carotenoids (nutrients that cannot be synthesized de novo) throughout the period of growth, and then provided adults with one of these two diets while simultaneously quantifying beak coloration and response to a variety of immune challenges. We found that both developmental and adult carotenoid supplementation increased circulating carotenoid levels during dietary treatment, but that birds that received low-carotenoid diets during development maintained relatively higher circulating carotenoid levels during an adult immune challenge. Individuals that received low levels of carotenoids during development had larger phytohemagglutinin (PHA)-induced cutaneous immune responses at adulthood; however, dietary treatment during development and adulthood did not affect antibody response to a novel antigen, nitric oxide production, natural antibody levels, hemolytic capacity of the plasma, or beak coloration. However, beak coloration prior to immune challenges positively predicted PHA response, and strong PHA responses were correlated with losses in carotenoid-pigmented coloration. In sum, we did not find consistent support for either the Environmental Matching or Silver Spoon hypotheses. We then describe a new hypothesis that should be tested in future studies examining developmental plasticity.
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Affiliation(s)
- Michael W Butler
- School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America.
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Sild E, Sepp T, Männiste M, Hõrak P. Carotenoid intake does not affect immune-stimulated oxidative burst in greenfinches. ACTA ACUST UNITED AC 2012; 214:3467-73. [PMID: 21957110 DOI: 10.1242/jeb.062182] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Carotenoid-based integument colouration is extremely widespread in the animal kingdom. It has been hypothesized that carotenoid colouration is used for communicating the health status of the bearers because carotenoids are efficient immunomodulators or antioxidants. However, the latter argument has been recently debated and the mechanisms by which carotenoids modulate immunity or oxidative balance are poorly known. We performed an experiment on wild-caught captive greenfinches, passerine birds with carotenoid-based plumage colouration, in order to test whether dietary carotenoid supplementation affects immune-stimulated oxidative burst of phagocytes in the whole blood and humoral immune response to a novel antigen, Brucella abortus (BA). Additionally, we tested whether immune stimulation with bacterial lipopolysaccharide (LPS) affects blood carotenoid levels. We thus tested the effects of carotenoids on the oxidative burst of phagocytes under neutral conditions and during in vivo immune challenge. LPS injection depleted plasma carotenoids, indicating involvement of these phytochemicals in the immune response. However, we did not find any evidence that manipulation of carotenoid intake had modulated anti-BA antibody production, LPS-stimulated oxidative burst of phagocytes, or basal levels of circulating reactive oxygen species. This indicates that carotenoid intake does not affect endogenous production of reactive oxygen species by immune cells. This finding is consistent with the view that carotenoids are unlikely to provide a direct link between oxidative stress and colouration. However, it remains to be tested whether the oxidative burst of phagocytes induced in our experiment actually inflicts oxidative damage and whether carotenoids play a role in the attenuation of such potential damages.
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Affiliation(s)
- Elin Sild
- Department of Zoology, Institute of Ecology and Earth Sciences, The Centre of Excellence FIBIR, Tartu University, Vanemuise 46, 51014 Tartu, Estonia
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Butler MW, McGraw KJ. Developmental immune history affects adult immune function but not carotenoid-based ornamentation in mallard ducks. Funct Ecol 2011. [DOI: 10.1111/j.1365-2435.2011.01942.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Orledge JM, Blount JD, Hoodless AN, Pike TW, Royle NJ. Synergistic effects of supplementation of dietary antioxidants during growth on adult phenotype in ring-necked pheasants,Phasianus colchicus. Funct Ecol 2011. [DOI: 10.1111/j.1365-2435.2011.01932.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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The carotenoid conundrum: improved nutrition boosts plasma carotenoid levels but not immune benefits of carotenoid supplementation. Oecologia 2011; 166:35-43. [PMID: 21301878 DOI: 10.1007/s00442-011-1921-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Accepted: 01/12/2011] [Indexed: 10/18/2022]
Abstract
Carotenoids are widely heralded as central to honest signaling due to their dual roles as pigments and antioxidants/immunostimulants. The aim of this study is to test if diet quality and carotenoids alone or in an interaction influence condition, carotenoid availability in plasma and immune responsiveness. Therefore, a diet experiment during the moult of great tits, Parus major, was performed. In a two-way design, we manipulated general quality (digestibility, protein and vitamin content) as well as carotenoid (lutein) content of semi-synthetic diets. Higher quality diet improved individual condition since birds had greater body mass, and to a lesser extent, higher hematocrit. In addition to the expected positive effect of carotenoid supplementation and individual lutein consumption on circulating lutein, there was a positive effect of enhanced diet quality on plasma carotenoid levels. Carotenoid supplementation, but not diet quality, improved the local inflammatory response and maintenance of body mass during a humoral immune reaction. The enhancement of circulating carotenoid levels by improved general quality of the diet or individual condition could provide a testable, mechanistic explanation for the variation in effects of carotenoid supplementation studies.
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Van Hout AJM, Eens M, Pinxten R. Carotenoid supplementation positively affects the expression of a non-visual sexual signal. PLoS One 2011; 6:e16326. [PMID: 21283591 PMCID: PMC3026812 DOI: 10.1371/journal.pone.0016326] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Accepted: 12/13/2010] [Indexed: 11/18/2022] Open
Abstract
Carotenoids are a class of pigments which are widely used by animals for the expression of yellow-to-red colour signals, such as bill or plumage colour. Since they also have been shown to promote immunocompetence and to function as antioxidants, many studies have investigated a potential allocation trade-off with respect to carotenoid-based signals within the context of sexual selection. Although an effect of carotenoids on non-visual (e.g. acoustic) signals involved in sexual selection has been hypothesized, this has to date not been investigated. First, we examined a potential effect of dietary carotenoid supplementation on overall song rate during the non-breeding season in captive male European starlings (Sturnus vulgaris). After only 3–7 days, we found a significant (body-mass independent) positive effect of carotenoid availability on overall song rate. Secondly, as a number of studies suggest that carotenoids could affect the modulation of sexual signals by plasma levels of the steroid hormone testosterone (T), we used the same birds to subsequently investigate whether carotenoid availability affects the increase in (nestbox-oriented) song rate induced by experimentally elevated plasma T levels. Our results suggest that carotenoids may enhance the positive effect of elevated plasma T levels on nestbox-oriented song rate. Moreover, while non-supplemented starlings responded to T-implantation with an increase in both overall song rate and nestbox-oriented song, carotenoid-supplemented starlings instead shifted song production towards (reproductively relevant) nestbox-oriented song, without increasing overall song rate. Given that song rate is an acoustic signal rather than a visual signal, our findings therefore indicate that the role of carotenoids in (sexual) signalling need not be dependent on their function as pigments.
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MCGRAW KEVINJ, NOLAN PAULM, CRINO ONDIL. Carotenoids bolster immunity during moult in a wild songbird with sexually selected plumage coloration. Biol J Linn Soc Lond 2011. [DOI: 10.1111/j.1095-8312.2010.01594.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Sepp T, Karu U, Sild E, Männiste M, Hõrak P. Effects of carotenoids, immune activation and immune suppression on the intensity of chronic coccidiosis in greenfinches. Exp Parasitol 2010; 127:651-7. [PMID: 21176774 DOI: 10.1016/j.exppara.2010.12.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Revised: 11/17/2010] [Accepted: 12/14/2010] [Indexed: 11/29/2022]
Abstract
Allocation trade-offs of carotenoids between their use in the immune system and production of integumentary colouration have been suggested as a proximate mechanism maintaining honesty of signal traits. We tested how dietary carotenoid supplementation, immune activation and immune suppression affect intensity of coccidian infection in captive greenfinches Carduelis chloris, a passerine with carotenoid-based plumage. Immune activation with phytohaemagglutinin (PHA) decreased body mass among birds not supplemented with lutein, while among the carotenoid-fed birds, PHA had no effect on mass dynamics. Immune suppression with dexamethasone (DEX) induced loss of body mass and reduced the swelling response to PHA. DEX and PHA increased the concentration of circulating heterophils. Lutein supplementation increased plasma carotenoid levels but had no effect on the swelling response induced by PHA. PHA and DEX treatments did not affect plasma carotenoids. Immune stimulation by PHA suppressed the infection, but only among carotenoid-supplemented birds. Priming of the immune system can thus aid in suppressing chronic infection but only when sufficient amount of carotenoids is available. Our experiment shows the importance of carotenoids in immune response, but also the complicated nature of this impact, which could be the reason for inconsistent results in studies investigating the immunomodulatory effects of carotenoids. The findings about involvement of carotenoids in modulation of an immune response against coccidiosis suggest that carotenoid-based ornaments may honestly signal individuals' ability to manage chronic infections.
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Affiliation(s)
- Tuul Sepp
- Department of Zoology, Institute of Ecology and Earth Sciences, Tartu University, Vanemuise 46, 51014 Tartu, Estonia.
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Pellitteri-Rosa D, Sacchi R, Galeotti P, Marchesi M, Fasola M. Do Hermann's tortoises (Testudo hermanni) discriminate colours? An experiment with natural and artificial stimuli. ACTA ACUST UNITED AC 2010. [DOI: 10.1080/11250000903464067] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Butler MW, McGraw KJ. Past or present? Relative contributions of developmental and adult conditions to adult immune function and coloration in mallard ducks (Anas platyrhynchos). J Comp Physiol B 2010; 181:551-63. [PMID: 21140156 DOI: 10.1007/s00360-010-0529-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Revised: 10/08/2010] [Accepted: 10/25/2010] [Indexed: 01/08/2023]
Abstract
Developmental conditions affect adult physiological processes and phenotypic traits, including those associated with both survival and reproduction. Carotenoids are molecules that generate sexually attractive coloration, and these pigments are acquired throughout life and can affect antioxidant capacity and immunocompetence of young and old animals. However, few studies have tracked carotenoid status and condition during development and into adulthood to understand how ontogeny affects later-life health and coloration of both males and females. We reared male and female mallard ducks (Anas platyrhynchos) from hatch to adulthood, measured circulating carotenoid titers and body condition (i.e., size-adjusted body mass) throughout development, and assessed adult immune function and integumentary carotenoid-based beak and foot coloration. We found that adult immune function (wing web swelling response to phytohemagglutinin; PHA) in males was positively correlated with body condition during the growth period of development, rather than adult condition, and similarly that both male and female beak coloration was associated with developmental, rather than adult, body condition. We also found associations between coloration and health during adulthood; males with more carotenoid-rich beaks (a sexually attractive feature) tended to have a more robust adult PHA response and a greater antibody response to a novel antigen, while females with less carotenoid-rich beaks had greater antibody responsiveness at adulthood. In addition, male beak color changed over the course of the 24-h PHA test in proportion to the degree of PHA swelling. However, intensity of foot coloration (a trait of unknown sexual significance) was not associated with any condition, carotenoid, or immune metric for males or females. Taken together, our findings implicate key developmental components to the expression of both survival- and reproduction-related traits at adulthood, but that for a dynamic trait like beak color, there are also important adult conditions that can alter signal expression.
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Affiliation(s)
- Michael W Butler
- School of Life Sciences, Arizona State University, PO Box 874601, Tempe, AZ 85287-4601, USA.
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Relationships between dietary carotenoids, body tissue carotenoids, parasite burden, and health state in wild mallard (Anas platyrhynchos) ducklings. Arch Biochem Biophys 2010; 504:154-60. [DOI: 10.1016/j.abb.2010.07.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Revised: 06/29/2010] [Accepted: 07/09/2010] [Indexed: 11/20/2022]
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Dietary antioxidants, lipid peroxidation and plumage colouration in nestling blue tits Cyanistes caeruleus. Naturwissenschaften 2010; 97:903-13. [DOI: 10.1007/s00114-010-0708-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Revised: 08/03/2010] [Accepted: 08/04/2010] [Indexed: 10/19/2022]
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Hõrak P, Sild E, Soomets U, Sepp T, Kilk K. Oxidative stress and information content of black and yellow plumage coloration: an experiment with greenfinches. J Exp Biol 2010; 213:2225-33. [PMID: 20543121 DOI: 10.1242/jeb.042085] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Carotenoid and melanin pigments in the plumage of birds are hypothesized to be sensitive to oxidative stress. We manipulated oxidative status of captive greenfinches (Carduelis chloris L.) by the administration of buthionine sulfoximine (BSO), a selective inhibitor of the synthesis of glutathione (GSH), an intracellular antioxidant. Half of the birds in the treated group, as well as in the control group, also received dietary carotenoid (lutein) supplementation. BSO treatment reduced erythrocyte GSH levels and caused oxidative damage as indicated by the increased concentration of plasma malondialdehyde (MDA), an end product of lipid peroxidation. BSO treatment also reduced the brightness (i.e. increased blackness) of the tips of tail feathers grown during the experiment. These results show that a low systemic GSH level is required for development of eumelanin plumage coloration and that such a low GSH level is also potentially dangerous for the organism. Carotenoid supplementation increased plasma carotenoid levels and chroma of the yellow parts of the feathers grown during the experiment. However, carotenoid supplementation did not reduce plasma MDA levels. Manipulation of GSH did not affect plasma carotenoids or carotenoid-based plumage coloration. These findings argue against the antioxidant function of lutein in vivo and carotenoid signaling of antioxidant status.
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Affiliation(s)
- Peeter Hõrak
- Department of Zoology, Institute of Ecology and Earth Sciences, The Centre of Excellence FIBIR, Tartu University, Vanemuise 46, 51014 Tartu, Estonia
| | - Elin Sild
- Department of Zoology, Institute of Ecology and Earth Sciences, The Centre of Excellence FIBIR, Tartu University, Vanemuise 46, 51014 Tartu, Estonia
| | - Ursel Soomets
- Department of Biochemistry, Medical Faculty; The Centre of Excellence for Translational Medicine, Tartu University, Ravila 19, 50411 Tartu, Estonia
| | - Tuul Sepp
- Department of Zoology, Institute of Ecology and Earth Sciences, The Centre of Excellence FIBIR, Tartu University, Vanemuise 46, 51014 Tartu, Estonia
| | - Kalle Kilk
- Department of Biochemistry, Medical Faculty; The Centre of Excellence for Translational Medicine, Tartu University, Ravila 19, 50411 Tartu, Estonia
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Kekäläinen J, Valkama H, Huuskonen H, Taskinen J. RESEARCH PAPER: Multiple Sexual Ornamentation Signals Male Quality and Predicts Female Preference in Minnows. Ethology 2010. [DOI: 10.1111/j.1439-0310.2010.01802.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Sepp T, Sild E, Hõrak P. Hematological condition indexes in greenfinches: effects of captivity and diurnal variation. Physiol Biochem Zool 2010; 83:276-82. [PMID: 20078208 DOI: 10.1086/648580] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Ecophysiological research aiming at explaining the causes and consequences of variation in individual condition, health state, and allostasis is traditionally performed on captive animals under controlled laboratory conditions. The question about how captivity per se affects studied parameters is therefore of central importance for generalizing the information gained from such studies. We addressed this question by comparing various indexes of physiological condition of wintering greenfinches sampled in the wild and kept in captivity for different time periods. Bringing wild greenfinches into captivity did not result in systematic alteration in nine of 12 physiological parameters studied. Captive birds had consistently lower plasma carotenoid and uric acid levels than wild ones. Variation in differential leukocyte counts did not reveal any signs of elevated stress of birds kept in captivity. These results indicate that for a number of physiological parameters, information obtained from captive animals can be generalized to natural situations. Variance in traits most closely related to physical exercise capacity (body mass and hematocrit) were much lower in the wild than in captivity. These findings suggest that under harsh environmental conditions experienced by wild birds (i.e., predation threat, scarce resources), traits such as hematocrit and body mass are fine tuned by physiological trade-offs.
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Affiliation(s)
- Tuul Sepp
- Institute of Ecology and Earth Sciences, Tartu University, Vanemuise 46, 51014 Tartu, Estonia.
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EDLER ALICEU, FRIEDL THOMASWP. Individual quality and carotenoid-based plumage ornaments in male red bishops (Euplectes orix): plumage is not all that counts. Biol J Linn Soc Lond 2010. [DOI: 10.1111/j.1095-8312.2009.01354.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Pap PL, Vágási CI, Czirják GA, Titilincu A, Pintea A, Barta Z. Carotenoids modulate the effect of coccidian infection on the condition and immune response in moulting house sparrows. ACTA ACUST UNITED AC 2009; 212:3228-35. [PMID: 19801427 DOI: 10.1242/jeb.031948] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In the present study, we experimentally manipulated coccidian parasitism and dietary carotenoid availability in a fully factorial experiment in male house sparrows (Passer domesticus Linnaeus), and tested whether carotenoid supplementation reduces the cost of parasitism in terms of condition, moult and immune responses. We found that coccidians have a significant but transient negative effect on body mass, which can be reduced if birds have access to carotenoid supplementation in their diet. Experimental manipulation had no significant effect on the moulting parameters of the birds measured following coccidian infestation and during the whole moulting period. Carotenoid supplementation increased the plasma carotenoid concentration in both infested and medicated birds treated with a coccidiostatic drug; however, after two months exposure to parasites, plasma carotenoid concentration increased only in the carotenoid-supplemented and medicated group whereas no difference was observed between the carotenoid-supplemented and infested and non-supplemented groups. On the contrary, coccidian infestation was not affected by carotenoid supplementation. Experimental infestation decreased the antibody response to sheep red blood cells (SRBCs), although no significant effect was observed in the capacity of the birds to respond to a mitogenic challenge with phytohemagglutinin. Within the experimentally infested groups birds with carotenoid-supplemented food tended to have an increased anti-SRBC humoral immune response. The positive correlation between coccidian infestation and the strength of the humoral immune response against SRBCs in the non-supplemented and infested groups indicates that this part of the immune system plays an important role in defence against these parasites.
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Affiliation(s)
- Péter László Pap
- Behavioural Ecology Research Group, Department of Evolutionary Zoology, University of Debrecen, H-4032 Debrecen, Egyetem tér 1, Hungary.
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Affiliation(s)
- Lorenzo Pérez-Rodríguez
- Instituto de Investigación en Recursos Cinegéticos, IREC (CSIC, UCLM, JCCM), Ciudad Real, Spain.
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Maternal effects and β-carotene assimilation in Canary chicks. Physiol Behav 2009; 96:389-93. [DOI: 10.1016/j.physbeh.2008.11.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2007] [Revised: 11/03/2008] [Accepted: 11/05/2008] [Indexed: 11/22/2022]
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Peters A, Delhey K, Andersson S, van Noordwijk H, Förschler MI. Condition-dependence of multiple carotenoid-based plumage traits: an experimental study. Funct Ecol 2008. [DOI: 10.1111/j.1365-2435.2008.01437.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Catoni C, Schaefer HM, Peters A. Fruit for health: the effect of flavonoids on humoral immune response and food selection in a frugivorous bird. Funct Ecol 2008. [DOI: 10.1111/j.1365-2435.2008.01400.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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