1
|
Duan G, Liu W, Han H, Li D, Lei Q, Zhou Y, Liu J, Wang J, Du Y, Cao D, Chen F, Li F. Transcriptome and histological analyses on the uterus of freckle egg laying hens. BMC Genomics 2023; 24:738. [PMID: 38049727 PMCID: PMC10696746 DOI: 10.1186/s12864-023-09828-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 11/22/2023] [Indexed: 12/06/2023] Open
Abstract
BACKGROUND In this study, we explored the characteristics and causes of freckle formation. We collected 15 normal and freckled eggs each for eggshell index testing and hypothesized that the structure and function of the uterus would have a direct effect on freckled egg production given that eggshells are formed in the uterus. To test this hypothesis, we collected uterine tissue from laying hens (418 days of age) that laid normal (Group C, n = 13) and freckled (Group T, n = 16) eggs for 7 consecutive days. RESULTS When we examined the eggshell quality, we found that the L value was significantly lower (P < 0.05) in the freckled site group of freckled eggs compared to the normal egg group during the detection of blunt pole, equator, and sharp pole of the eggshell color. The a-values of the three positions were significantly higher (P < 0.05) in the freckled site group of freckled eggs, and the a-values of the blunt pole were significantly lower (P < 0.05) in the background site group of freckled eggs, compared to the normal egg group. The b-values were significantly higher (P < 0.05) at three locations in the freckled site group of freckled eggs compared to the normal egg group. During the detection of eggshell thickness, the blunt pole was significantly higher (P < 0.05) in the freckled egg site group of freckled eggs compared to the normal egg group, and there was no significant difference between the other groups (P > 0.05). There was no significant difference (P > 0.05) between the transverse and longitudinal diameters of the eggs in each group.We then performed histopathology and transcriptome analyses on the collected tissue. When compared with group C, uterine junctional epithelial cells in group T showed significant defects and cilia loss, and epithelial tissue was poorly intact. From transcriptomics, genes that met (|log2FC|) ≥ 1 and P < 0.05 criteria were screened as differentially expressed genes (DEGs). We identified a total of 136 DEGs, with 101 up- and 35 down-regulated genes from our RNA-seq data. DEGs identified by enrichment analyses, which were potentially associated with freckled egg production were: IFI6, CCL19, AvBD10, AvBD11, S100A12, POMC, and UCN3. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses showed that pathways were associated with immunoreaction and stress stimulation, e.g., complement activation, interleukin-1 cell reactions, viral responses, cell reactions stimulated by corticotropin releasing hormone, steroid hormone mediated signaling pathways, staphylococcal infections, B cell receptor signaling pathways, and natural killer cell mediated cytotoxicity. CONCLUSIONS From these data, freckled areas deepen freckled eggshell color, but background areas are not affected. At the same time,we reasoned that freckle eggs may result from abnormal immune responses and impaired uterine functions induced by stress. Therefore, the uterus of laying hens in a state of stress and abnormal immune function can cause the appearance of freckled eggs.
Collapse
Affiliation(s)
- Guochao Duan
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, China
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, 266109, China
| | - Wei Liu
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, China
- Poultry Breeding Engineering Technology Center of Shandong Province, Jinan, 250100, China
| | - Haixia Han
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, China
- Poultry Breeding Engineering Technology Center of Shandong Province, Jinan, 250100, China
| | - Dapeng Li
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, China
- Poultry Breeding Engineering Technology Center of Shandong Province, Jinan, 250100, China
| | - Qiuxia Lei
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, China
- Poultry Breeding Engineering Technology Center of Shandong Province, Jinan, 250100, China
| | - Yan Zhou
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, China
- Poultry Breeding Engineering Technology Center of Shandong Province, Jinan, 250100, China
| | - Jie Liu
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, China
- Poultry Breeding Engineering Technology Center of Shandong Province, Jinan, 250100, China
| | - Jie Wang
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, China
- Poultry Breeding Engineering Technology Center of Shandong Province, Jinan, 250100, China
| | - Yuanjun Du
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, China
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, 266109, China
| | - Dingguo Cao
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, China
- Poultry Breeding Engineering Technology Center of Shandong Province, Jinan, 250100, China
| | - Fu Chen
- College of Veterinary Medicine, Qingdao Agricultural University, Qingdao, 266109, China
| | - Fuwei Li
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan, 250100, China.
- Poultry Breeding Engineering Technology Center of Shandong Province, Jinan, 250100, China.
| |
Collapse
|
2
|
Yang J, Mao Z, Wang X, Zhuang J, Gong S, Gao Z, Xu G, Yang N, Sun C. Identification of crucial genes and metabolites regulating the eggshell brownness in chicken. BMC Genomics 2022; 23:761. [PMID: 36411402 PMCID: PMC9677642 DOI: 10.1186/s12864-022-08987-7] [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: 08/06/2022] [Accepted: 11/03/2022] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Protoporphyrin IX (Pp IX) is the primary pigment for brown eggshells. However, the regulatory mechanisms directing Pp IX synthesis, transport, and genetic regulation during eggshell calcification in chickens remain obscure. In this study, we investigated the mechanism of brown eggshell formation at different times following oviposition, using White Leghorn hens (WS group), Rhode Island Red light brown eggshell line hens (LBS group) and Rhode Island Red dark brown eggshell line hens (DBS group). RESULTS At 4, 16 and 22 h following oviposition, Pp IX concentrations in LBS and DBS groups were significantly higher in shell glands than in liver (P < 0.05). Pp IX concentrations in shell glands of LBS and DBS groups at 16 and 22 h following oviposition were significantly higher than WS group (P < 0.05). In comparative transcriptome analysis, δ-aminolevulinate synthase 1 (ALAS1), solute carrier family 25 member 38 (SLC25A38), ATP binding cassette subfamily G member 2 (ABCG2) and feline leukemia virus subgroup C cellular receptor 1 (FLVCR1), which were associated with Pp IX synthesis, were identified as differentially expressed genes (DEGs). RT-qPCR results showed that the expression level of ALAS1 in shell glands was significantly higher in DBS group than in WS group at 16 and 22 h following oviposition (P < 0.05). In addition, four single nucleotide polymorphisms (SNPs) in ALAS1 gene that were significantly associated with eggshell brownness were identified. By identifying the differential metabolites in LBS and DBS groups, we found 11-hydroxy-E4-neuroprostane in shell glands and 15-dehydro-prostaglandin E1(1-) and prostaglandin G2 2-glyceryl ester in uterine fluid were related to eggshell pigment secretion. CONCLUSIONS In this study, the regulatory mechanisms of eggshell brownness were studied comprehensively by different eggshell color and time following oviposition. Results show that Pp IX is synthesized de novo and stored in shell gland, and ALAS1 is a key gene regulating Pp IX synthesis in the shell gland. We found three transporters in Pp IX pathway and three metabolites in shell glands and uterine fluid that may influence eggshell browning.
Collapse
Affiliation(s)
- Jing Yang
- grid.22935.3f0000 0004 0530 8290National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193 China
| | - Zhiqiong Mao
- Beinongda Technology Co,.Ltd, Beijing, 100083 China
| | - Xiqiong Wang
- grid.22935.3f0000 0004 0530 8290National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193 China
| | - Jingjie Zhuang
- grid.22935.3f0000 0004 0530 8290National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193 China
| | - Sijia Gong
- grid.22935.3f0000 0004 0530 8290National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193 China
| | - Zhouyang Gao
- grid.22935.3f0000 0004 0530 8290National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193 China
| | - Guiyun Xu
- grid.22935.3f0000 0004 0530 8290National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193 China
| | - Ning Yang
- grid.22935.3f0000 0004 0530 8290National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193 China
| | - Congjiao Sun
- grid.22935.3f0000 0004 0530 8290National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, 100193 China
| |
Collapse
|
3
|
Research progress on bird eggshell quality defects: a review. Poult Sci 2022; 102:102283. [PMID: 36399932 PMCID: PMC9673113 DOI: 10.1016/j.psj.2022.102283] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 10/18/2022] [Accepted: 10/18/2022] [Indexed: 11/05/2022] Open
Abstract
The eggshell quality declined with extending of chicken laying cycles. Eggshell quality is a crucial feature that not only affects consumer preference, but also influences producers' economic profitability. The eggshell ultrastructure consists of mammillary, palisade, and vertical crystal layers. Any defect in shell structure results in a reduction in eggshell quality. Speckled, translucent, pimpled, and soft eggshells are common defects that cause significant financial losses for farmers and food security concerns for consumers. Therefore, reducing the faulty eggshells is critical for poultry production. Defective eggshell quality has been attributed to hereditary factors and external environmental stimuli. As such, improvements can be carried out through selective breeding and environmental control of components such as temperature, moisture, and diet formula balance. In this review, the molecular mechanisms of the main eggshell quality defects (speckled, translucent, pimpled, broken, and soft-shell eggs) and the relevant improvement methods are detailed. We hope this review will serve as a useful resource for poultry production management and effectively increasing eggshell quality.
Collapse
|
4
|
Holveck MJ, Guerreiro R, Perret P, Doutrelant C, Grégoire A. Eggshell coloration indicates female condition during egg-laying: a field experiment in blue tits. Biol J Linn Soc Lond 2019. [DOI: 10.1093/biolinnean/blz082] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AbstractSeveral selection pressures may explain the evolution of avian eggshell coloration patterns. In cavity-nesting species, there are two main non-exclusive hypotheses. The sexually selected eggshell colour hypothesis proposes that eggshell coloration is a sexually selected signal of female and offspring quality used by males that influences paternal care or future re-mating decisions. The structural function hypothesis proposes that pigments help strengthen the eggshell and are present at higher levels and at the blunt end of the egg when females face calcium shortages. We tested whether eggshell coloration (brown spots on a white ground colour) in blue tits (Cyanistes caeruleus) could reliably indicate female condition at laying by forcing females to produce two consecutive clutches, thus increasing their reproductive costs. Three measures of eggshell coloration – the area covered by spots as well as white ground UV-chroma and brightness – changed between clutches; the fourth measure, spot distribution, did not. The changes were more dramatic in young and lower-quality females. All the measures varied with female quality (i.e. body condition and/or laying date). Overall, higher-quality females produced more colourful (larger, more concentrated spotted surface area; higher UV-chroma) and less bright (i.e. putatively more pigmented) eggshells, a result that is generally in line with past research. We found a clear empirical link between eggshell coloration and female condition in blue tits, an important step in determining whether eggshell coloration is a sexual signal, but which does not exclude a potential concomitant structural function.
Collapse
Affiliation(s)
- Marie-Jeanne Holveck
- CEFE UMR 5175, Univ Montpellier, CNRS, Univ Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France
| | - Romain Guerreiro
- CEFE UMR 5175, Univ Montpellier, CNRS, Univ Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France
| | - Philippe Perret
- CEFE UMR 5175, CNRS, Univ Montpellier, Univ Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France
| | - Claire Doutrelant
- CEFE UMR 5175, CNRS, Univ Montpellier, Univ Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France
| | - Arnaud Grégoire
- CEFE UMR 5175, Univ Montpellier, CNRS, Univ Paul Valéry Montpellier 3, EPHE, IRD, Montpellier, France
| |
Collapse
|
5
|
Hoi H, Darolová A, Krištofík J, Poláček M, Majtán J, Zeman M, Okuliarová M, Turčoková L, Knauer F. Covariation between eggshell colouration and eggshell bacteria abundance and egg characteristics in blackbirds. ETHOL ECOL EVOL 2019. [DOI: 10.1080/03949370.2019.1575910] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Herbert Hoi
- Department of Integrative Biology and Evolution, Konrad Lorenz Institute of Ethology, University of Veterinary Medicine, Savoyenstrasse 1a, 1160 Vienna, Austria
| | - Alžbeta Darolová
- Department of Animal Ecology, Institute of Zoology, Slovak Academy of Sciences, Dúbravská cesta 9, 845 06 Bratislava, Slovakia
| | - Ján Krištofík
- Department of Animal Ecology, Institute of Zoology, Slovak Academy of Sciences, Dúbravská cesta 9, 845 06 Bratislava, Slovakia
| | - Miroslav Poláček
- Department of Integrative Biology and Evolution, Konrad Lorenz Institute of Ethology, University of Veterinary Medicine, Savoyenstrasse 1a, 1160 Vienna, Austria
| | - Juraj Majtán
- Department of Microbiology, Institute of Molecular Biology, Slovak Academy of Sciences, Dúbravská cesta 9, 845 06 Bratislava, Slovakia
| | - Michal Zeman
- Department of Animal Physiology and Ethology, Faculty of Natural Sciences, Comenius University, Ilkovičova 6, 842 15 Bratislava, Slovakia
| | - Monika Okuliarová
- Department of Animal Physiology and Ethology, Faculty of Natural Sciences, Comenius University, Ilkovičova 6, 842 15 Bratislava, Slovakia
| | - Lucia Turčoková
- Department of Zoology, Faculty of Natural Sciences, Comenius University, Ilkovičova 6, 842 15 Bratislava, Slovakia
| | - Felix Knauer
- Department of Integrative Biology and Evolution, Research Institute of Wildlife Ecology, University of Veterinary Medicine, Savoyenstrasse 1, 1160 Vienna, Austria
| |
Collapse
|
6
|
L'Herpiniere KL, O'Neill LG, Russell AF, Duursma DE, Griffith SC. Unscrambling variation in avian eggshell colour and patterning in a continent-wide study. ROYAL SOCIETY OPEN SCIENCE 2019; 6:181269. [PMID: 30800374 PMCID: PMC6366205 DOI: 10.1098/rsos.181269] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 01/09/2019] [Indexed: 06/09/2023]
Abstract
The evolutionary drivers underlying marked variation in the pigmentation of eggs within many avian species remains unclear. The leading hypotheses proposed to explain such variation advocate the roles of genetic differences, signalling and/or structural integrity. One means of testing among these hypotheses is to capitalize on museum collections of eggs obtained throughout a broad geographical range of a species to ensure sufficient variation in predictors pertaining to each hypothesis. Here, we measured coloration and patterning in eggs from 272 clutches of Australian magpies (Cracticus tibicen) collected across most of their geographical range of ca 7 million km2; encompassing eight subspecies, variation in environmental parameters, and the presence/absence of a brood parasite. We found considerable variation in background colour, as well as in the extent and distribution of patterning across eggs. There was little evidence that this variation was explained by subspecies or the contemporary presence of a brood parasite. However, measures of maximum temperature, leaf area index and soil calcium all contributed to variation in egg appearance, although their explanatory power was relatively low. Our results suggest that multiple factors combine to influence egg appearance in this species, and that even in species with highly variable eggs, coloration is not readily explained.
Collapse
Affiliation(s)
- Kiara L. L'Herpiniere
- Department of Biological Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
| | - Louis G. O'Neill
- Department of Biological Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
- Centre for Ecology and Conservation, University of Exeter Cornwall Campus, Penryn TR10 9FE, UK
| | - Andrew F. Russell
- Centre for Ecology and Conservation, University of Exeter Cornwall Campus, Penryn TR10 9FE, UK
| | - Daisy Englert Duursma
- Department of Biological Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
| | - Simon C. Griffith
- Department of Biological Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
| |
Collapse
|
7
|
Hargitai R, Boross N, Hámori S, Neuberger E, Nyiri Z. Eggshell Biliverdin and Protoporphyrin Pigments in a Songbird: Are They Derived from Erythrocytes, Blood Plasma, or the Shell Gland? Physiol Biochem Zool 2017; 90:613-626. [DOI: 10.1086/694297] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
8
|
|
9
|
Fronstin RB, Doucet SM, Christians JK. Haematocrit, eggshell colouration and sexual signaling in the European starling (Sturnus vulgaris). BMC Ecol 2016; 16:31. [PMID: 27349389 PMCID: PMC4922052 DOI: 10.1186/s12898-016-0084-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 06/02/2016] [Indexed: 11/29/2022] Open
Abstract
Background One hypothesis to explain the blue–green colour of the eggs of many bird species is that it is a sexually-selected signal of the laying female’s quality, which males use to determine their investment. This hypothesis requires that eggshell pigmentation carries a cost or is otherwise linked to female quality. One potential cost is that biliverdin, a haem derivative and the pigment responsible for eggshell colouration, is limiting. To assess this potential cost, we attempted to manipulate haematocrit and haemoglobin in free-living European starlings (Sturnus vulgaris Linnaeus). Upon collecting unmanipulated first clutches, we treated females with phenylhydrazine (PHZ), a haemolytic agent, and measured the blue–green chroma and reproductive performance of replacement clutches. We also investigated whether eggshell colour was associated with haematocrit or haemoglobin levels in unmanipulated first clutches. To test whether eggshell colour might act as a sexual signal, we examined associations between eggshell colour and reproductive performance, as well as the provisioning rate of the male. Results PHZ-treatment did not affect eggshell colour in replacement clutches. In unmanipulated first clutches, eggshell colour was not correlated with haematocrit or haemoglobin levels. Eggshell colour was correlated with female mass in unmanipulated first clutches but not replacement clutches. Chicks from eggs with higher eggshell colour had higher haemoglobin levels and longer tarsi just prior to fledging, suggesting that eggshell colour could reflect brood quality. However, eggshell colour was not correlated with the provisioning rate of the male or any other measure of reproductive performance. Conclusions We found no evidence to support the hypothesis that the availability of resources required for the synthesis of pigment limits eggshell colour in European starlings, or that eggshell colour is used by males to determine their level of reproductive investment. We found little evidence that eggshell colour is correlated with female or offspring quality in this species. Electronic supplementary material The online version of this article (doi:10.1186/s12898-016-0084-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Raime B Fronstin
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A 1S6, Canada.
| | - Stephanie M Doucet
- Department of Biological Sciences, University of Windsor, 401 Sunset Avenue, Biology Building, Windsor, ON, Canada
| | - Julian K Christians
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC, V5A 1S6, Canada
| |
Collapse
|
10
|
Espín S, Ruiz S, Sánchez-Virosta P, Salminen JP, Eeva T. Effects of experimental calcium availability and anthropogenic metal pollution on eggshell characteristics and yolk carotenoid and vitamin levels in two passerine birds. CHEMOSPHERE 2016; 151:189-201. [PMID: 26943740 DOI: 10.1016/j.chemosphere.2016.02.074] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 02/14/2016] [Accepted: 02/16/2016] [Indexed: 06/05/2023]
Abstract
The maternal investment into egg quality depends on the condition of the female, the quality of the mate, and the quality of the environment. In that sense, availability of nutrients and exposure to pollutants are essential parameters to consider. The main aim of this study is to assess the effects of calcium (Ca) availability and anthropogenic metal pollution on early-stage reproduction in two passerine species, great tits (Parus major) and pied flycatchers (Ficedula hypoleuca), inhabiting a Ca-poor and metal-polluted area in SW Finland. Both species were able to obtain sufficient Ca for eggshell formation, and metal pollution was below the level of having negative effects in the egg size and eggshell characteristics. However, metal polluted environment negatively affected yolk lutein and vitamin D3 levels in both species, probably because of a lower access to carotenoid-rich diet and higher metal interference with vitamin D3 metabolism. The higher levels of vitamin D3 in yolks in the unpolluted zone could also be due to upregulated D3 levels as a response to the lower natural Ca availability. Yolk carotenoids and vitamin D3 were positively associated with nestling growth and size, supporting their importance for the appropriate chick development. The interspecific differences in yolk nutrient concentrations possibly reflect the different growth rate of these species. Pied flycatchers are likely adapted to low Ca availability through an efficient vitamin D3 metabolism, but their Ca intake could be close to a deficient level.
Collapse
Affiliation(s)
- Silvia Espín
- Section of Ecology, Department of Biology, University of Turku, 20014, Turku, Finland.
| | - Sandra Ruiz
- Section of Ecology, Department of Biology, University of Turku, 20014, Turku, Finland.
| | - Pablo Sánchez-Virosta
- Section of Ecology, Department of Biology, University of Turku, 20014, Turku, Finland.
| | - Juha-Pekka Salminen
- Laboratory of Organic Chemistry and Chemical Biology, Department of Chemistry, University of Turku, 20014, Turku, Finland.
| | - Tapio Eeva
- Section of Ecology, Department of Biology, University of Turku, 20014, Turku, Finland.
| |
Collapse
|
11
|
Holveck MJ, Grégoire A, Staszewski V, Guerreiro R, Perret P, Boulinier T, Doutrelant C. Eggshell spottiness reflects maternally transferred antibodies in blue tits. PLoS One 2012; 7:e50389. [PMID: 23226272 PMCID: PMC3511563 DOI: 10.1371/journal.pone.0050389] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Accepted: 10/23/2012] [Indexed: 11/19/2022] Open
Abstract
Blue-green and brown-spotted eggshells in birds have been proposed as sexual signals of female physiological condition and egg quality, reflecting maternal investment in the egg. Testing this hypothesis requires linking eggshell coloration to egg content, which is lacking for brown protoporphyrin-based pigmentation. As protoporphyrins can induce oxidative stress, and a large amount in eggshells should indicate either high female and egg quality if it reflects the female's high oxidative tolerance, or conversely poor quality if it reflects female physiological stress. Different studies supported either predictions but are difficult to compare given the methodological differences in eggshell-spottiness measurements. Using the blue tit Cyanistes caeruleus as a model species, we aimed at disentangling both predictions in testing if brown-spotted eggshell could reflect the quality of maternal investment in antibodies and carotenoids in the egg, and at improving between-study comparisons in correlating several common measurements of eggshell coloration (spectral and digital measures, spotted surface, pigmentation indices). We found that these color variables were weakly correlated highlighting the need for comparable quantitative measurements between studies and for multivariate regressions incorporating several eggshell-color characteristics. When evaluating the potential signaling function of brown-spotted eggshells, we thus searched for the brown eggshell-color variables that best predicted the maternal transfer of antibodies and carotenoids to egg yolks. We also tested the effects of several parental traits and breeding parameters potentially affecting this transfer. While eggshell coloration did not relate to yolk carotenoids, the eggs with larger and less evenly-distributed spots had higher antibody concentrations, suggesting that both the quantity and distribution of brown pigments reflected the transfer of maternal immune compounds in egg yolks. As yolk antibody concentrations were also positively related to key proxies of maternal quality (egg volume, number, yellow feather brightness, tarsus length), eggshells with larger spots concentrated at their broad pole may indicate higher-quality eggs.
Collapse
Affiliation(s)
- Marie-Jeanne Holveck
- Ecologie Evolutive, Centre d'Ecologie Fonctionnelle et Evolutive (CEFE-CNRS), Montpellier, France.
| | | | | | | | | | | | | |
Collapse
|
12
|
Stoddard MC, Fayet AL, Kilner RM, Hinde CA. Egg speckling patterns do not advertise offspring quality or influence male provisioning in great tits. PLoS One 2012; 7:e40211. [PMID: 22815730 PMCID: PMC3398933 DOI: 10.1371/journal.pone.0040211] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Accepted: 06/02/2012] [Indexed: 12/03/2022] Open
Abstract
Many passerine birds lay white eggs with reddish brown speckles produced by protoporphyrin pigment. However, the function of these spots is contested. Recently, the sexually selected eggshell coloration (SSEC) hypothesis proposed that eggshell color is a sexually selected signal through which a female advertises her quality (and hence the potential quality of her future young) to her male partner, thereby encouraging him to contribute more to breeding attempts. We performed a test of the SSEC hypothesis in a common passerine, the great tit Parus major. We used a double cross-fostering design to determine whether males change their provisioning behavior based on eggshell patterns they observe at the nest. We also tested the assumption that egg patterning reflects female and/or offspring quality. Because birds differ from humans in their color and pattern perception, we used digital photography and models of bird vision to quantify egg patterns objectively. Neither male provisioning nor chick growth was related to the pattern of eggs males observed during incubation. Although heavy females laid paler, less speckled eggs, these eggs did not produce chicks that grew faster. Therefore, we conclude that the SSEC hypothesis is an unlikely explanation for the evolution of egg speckling in great tits.
Collapse
|
13
|
Duval C, Cassey P, Mikšík I, Reynolds J, Spencer K. Condition-dependent strategies of eggshell pigmentation: an experimental study of Japanese quail (Coturnix coturnix japonica). J Exp Biol 2012; 216:700-8. [DOI: 10.1242/jeb.077370] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Summary
A relationship has been suggested between eggshell colour and female body condition based on the opposing antioxidant properties of the two main eggshell pigments: the antioxidant biliverdin (blue-green) and the pro-oxidant protoporphyrin (brown). We hypothesised that experimentally food-restricted females with low antioxidant capacity would deposit more protoporphyrin and less biliverdin in their eggshells, resulting in eggshells of reduced brightness but increased colour intensity. Two eggs were collected at the beginning and two at the end of a 2-week period from each of 24 female Japanese quails that were either food-restricted or receiving ad libitum food (i.e. controls) during that time. Reflectance spectra were recorded and analysed using spectral shape descriptors, chromatic and achromatic contrasts were computed accounting for avian visual sensitivities, and eggshell pigments were quantified. We examined both spot and background pigmentation and found no significant effect of food restriction on eggshell reflectance. However, food-restricted females in lower body condition increased the deposition of protoporphyrin and decreased the amount of biliverdin invested into their eggshells. We hypothesise that in species laying brown-spotted eggshells, females modulate eggshell pigment investment in response to their body condition. According to this hypothesis, we predict that females maintain eggshell colour to limit visible changes that could be detected by predators and thereby conceal their eggs, although this work has yet to be conducted. We suggest that further experimental work on egg camouflage under different environmental conditions will elaborate the process of pigment deposition and the physiological costs to females of laying heavily pigmented eggshells.
Collapse
Affiliation(s)
| | | | - Ivan Mikšík
- Institute of Physiology, Academy of Sciences of the Czech Republic
| | | | | |
Collapse
|