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1.
Ecotoxicol Environ Saf ; 161: 746-754, 2018 10.
Article in English | MEDLINE | ID: mdl-29957582

ABSTRACT

Humans are responsible for land-cover changes resulting in the emission of hazardous chemical elements including metallic trace elements i.e. MTEs. As a consequence, urban wildlife is exposed to high concentrations of MTEs, which exposure is linked to reproductive impairments. MTE effects on reproduction outputs might result from MTE exposure disrupting the endocrine pathways involved in reproductive behaviours. In birds, there is strong evidence that prolactin, corticosterone and testosterone are all involved in the regulation of parental effort during incubation and chick rearing. Endocrine-disrupting chemicals might stimulate or inhibit the production of those hormones and consequently alter parental investment and reproductive success outcomes. We measured baseline corticosterone, prolactin and testosterone plasma levels, and the corticosterone stress response of breeding feral pigeons (Columba livia) experimentally exposed to ecologically relevant lead and/or zinc concentrations. Independently of lead and/or zinc exposure, male and female plasma levels of corticosterone and prolactin (but not testosterone) showed temporal variations along the reproduction stages (i.e. incubation, early rearing and late rearing). In addition, both hatching and fledging success were slightly correlated with corticosterone, prolactin and testosterone levels. However, our study did not find any influence of lead or zinc exposure on hormone levels, suggesting that MTE effects on reproductive outputs might not be explained by MTE-induced modifications of corticosterone, prolactin and testosterone-linked behaviours during incubation and rearing. Alternatively, MTE-induced reproductive impairments might result from MTE exposure having direct effects on offspring phenotypes or prenatal indirect effects on the embryo (e.g. maternal transfer of MTEs, hormones or immune compounds).


Subject(s)
Columbidae/physiology , Environmental Pollutants/toxicity , Lead/toxicity , Reproduction/drug effects , Zinc/toxicity , Animals , Breeding , Columbidae/blood , Corticosterone/blood , Female , Male , Prolactin/blood , Testosterone/blood , Trace Elements/toxicity
2.
Proc Biol Sci ; 285(1879)2018 05 30.
Article in English | MEDLINE | ID: mdl-29848644

ABSTRACT

The role of parasites in shaping melanin-based colour polymorphism, and the consequences of colour polymorphism for disease resistance, remain debated. Here we review recent evidence of the links between melanin-based coloration and the behavioural and immunological defences of vertebrates against their parasites. First we propose that (1) differences between colour morphs can result in variable exposure to parasites, either directly (certain colours might be more or less attractive to parasites) or indirectly (variations in behaviour and encounter probability). Once infected, we propose that (2) immune variation between differently coloured individuals might result in different abilities to cope with parasite infection. We then discuss (3) how these different abilities could translate into variable sexual and natural selection in environments varying in parasite pressure. Finally, we address (4) the potential role of parasites in the maintenance of melanin-based colour polymorphism, especially in the context of global change and multiple stressors in human-altered environments. Because global change will probably affect both coloration and the spread of parasitic diseases in the decades to come, future studies should take into account melanin-based coloration to better predict the evolutionary responses of animals to changing disease risk in human-altered environments.


Subject(s)
Climate Change , Host-Parasite Interactions , Melanins/physiology , Pigmentation/physiology , Vertebrates/physiology , Animals , Color
3.
J Exp Biol ; 220(Pt 4): 573-581, 2017 02 15.
Article in English | MEDLINE | ID: mdl-27913599

ABSTRACT

Poor environmental conditions experienced during early development can have negative long-term consequences on fitness. Animals can compensate for negative developmental effects through phenotypic plasticity by diverting resources from non-vital to vital traits such as spatial memory to enhance foraging efficiency. We tested in young feral pigeons (Columba livia) how diets of different nutritional value during development affect the capacity to retrieve food hidden in a spatially complex environment, a process we refer to as 'spatial memory'. Parents were fed with either high- or low-quality food from egg laying until young fledged, after which all young pigeons received the same high-quality diet until memory performance was tested at 6 months of age. The pigeons were trained to learn a food location out of 18 possible locations in one session, and then their memory of this location was tested 24 h later. Birds reared with the low-quality diet made fewer errors in the memory test. These results demonstrate that food quality during development has long-lasting effects on memory, with a moderate nutritional deficit improving spatial memory performance in a foraging context. It might be that under poor feeding conditions resources are redirected from non-vital to vital traits, or pigeons raised with low-quality food might be better in using environmental cues such as the position of the sun to find where food was hidden.


Subject(s)
Appetitive Behavior , Columbidae/growth & development , Food Quality , Spatial Learning , Animal Feed/analysis , Animal Nutritional Physiological Phenomena , Animals , Columbidae/physiology , Female , Male , Memory Consolidation , Spatial Memory
4.
Physiol Biochem Zool ; 89(3): 206-12, 2016.
Article in English | MEDLINE | ID: mdl-27153130

ABSTRACT

Maternal early transfers of immune components influence eggs' hatching probability and nestlings' survival. They depend on females' own immunity and, because they are costly, on their physiological state. Therefore, trace metals, whether toxic and immunosuppressive (e.g., lead, cadmium, etc.) or necessary and immunostimulant (e.g., zinc, copper, iron, etc.), are likely to affect the amount of immune components transferred into the eggs. It may also vary with plumage eumelanin level, which is known to be linked to immunity, to transfer of antibodies, and to metal detoxification. In feral pigeons (Columba livia) injected with an antigen and experimentally exposed to lead and/or zinc (two highly abundant trace metals in urban areas), we measured specific antibody transfer and concentrations of two antimicrobial proteins (lysozyme and ovotransferrin) in eggs. As expected, lead had negative effects on specific antibody transfer, while zinc positively affected lysozyme egg concentrations. Moreover, eggs from lead-exposed females exhibited higher ovotransferrin concentrations; because it binds metal ions, ovotransferrin may enable egg detoxification and embryo protection. Finally, eggs' lysozyme concentrations increased with plumage darkness of females not exposed to zinc, while the relation was opposite among zinc-exposed females, suggesting that benefits and costs of plumage melanism depend on trace metal environmental levels. Overall, our study underlines the potential ecotoxicological effects of trace metals on maternal transfers of immune components and the role of plumage melanism in modulating these effects.


Subject(s)
Antibodies/metabolism , Columbidae/metabolism , Environmental Pollutants/toxicity , Immunity, Maternally-Acquired/drug effects , Lead/toxicity , Zinc/toxicity , Animals , Columbidae/immunology , Conalbumin/metabolism , Female , Hemocyanins/immunology , Muramidase/metabolism , Ovum/immunology , Trace Elements
5.
Ecotoxicology ; 25(3): 521-9, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26809976

ABSTRACT

Understanding the effects of trace metals emitted by anthropogenic activities on wildlife is of great concern in urban ecology; yet, information on how they affect individuals, populations, communities and ecosystems remains scarce. In particular, trace metals may impact survival by altering the immune system response to parasites. Plumage melanin is assumed to influence the effects of trace metals on immunity owing to its ability to bind metal ions in feathers and its synthesis being coded by a pleiotropic gene. We thus hypothesized that trace metal exposure would interact with plumage colouration in shaping immune response. We experimentally investigated the interactive effect between exposure to an environmentally relevant range of zinc and/or lead and melanin-based plumage colouration on components of the immune system in feral pigeons (Columba livia). We found that zinc increased anti-keyhole limpet hemocyanin (KLH) IgY primary response maintenance, buffered the negative effect of lead on anti-KLH IgY secondary response maintenance and tended to increase T-cell mediated phytohaemagglutinin (PHA) skin response. Lead decreased the peak of the anti-KLH IgY secondary response. In addition, pheomelanic pigeons exhibited a higher secondary anti-KLH IgY response than did eumelanic ones. Finally, T-cell mediated PHA skin response decreased with increasing plumage eumelanin level of birds exposed to lead. Neither treatments nor plumage colouration correlated with endoparasite intensity. Overall, our study points out the effects of trace metals on some parameters of birds' immunity, independently from other confounding urbanization factors, and underlines the need to investigate their impacts on other life history traits and their consequences in the ecology and evolution of host-parasite interactions.


Subject(s)
Columbidae/immunology , Columbidae/metabolism , Environmental Monitoring , Environmental Pollutants/toxicity , Melanins/metabolism , Metals/toxicity , Animals
6.
Biol Lett ; 11(11)2015 Nov.
Article in English | MEDLINE | ID: mdl-26559513

ABSTRACT

Maternal antibodies (MatAb) are known to provide passive protection early in life for young vertebrates but their effects on the development of offspring immune response across generations are still unknown. Here, we investigated the effects of antigen exposure (keyhole limpet haemocyanin, KLH) experienced by urban pigeon (Columba livia) females on the amount of antigen-specific antibodies (Abs) transferred into the egg yolk of their daughters and on the humoural immune response towards this same antigen in their grandchildren. We found that chicks from KLH-injected maternal grandmothers had a higher humoural response than chicks from sham-injected grandmothers. However, we did not detect a significant effect of female KLH exposure on the ability of their daughters to transmit anti-KLH Abs into their eggs. These results suggest that antigen exposure at one generation may shape the immune profile of offspring over two next generations, although the underlying mechanisms remain to be investigated.


Subject(s)
Columbidae/immunology , Animals , Antibodies/immunology , Columbidae/growth & development , Egg Yolk/immunology , Female , Hemocyanins/immunology , Hemocyanins/pharmacology , Immunity, Humoral , Male
7.
Biol Lett ; 10(3): 20140164, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24671830

ABSTRACT

Trace metals produced by anthropogenic activities are of major importance in urban areas and might constitute a new evolutionary force selecting for the ability to cope with their deleterious effects. Interestingly, melanin pigments are known to bind metal ions, thereby potentially sequestering them in inert body parts such as coat and feathers, and facilitating body detoxification. Thus, a more melanic plumage or coat coloration could bring a selective advantage for animals living in polluted areas. We tested this hypothesis by investigating the link between melanin-based coloration and zinc and lead concentrations in feathers of urban feral pigeons, both at capture time and after one year of captivity in standardized conditions. Results show that differently coloured pigeons had similar metal concentrations at capture time. Metal concentrations strongly decreased after one year in standardized conditions, and more melanic pigeons had higher concentrations of zinc (but not lead) in their feathers. This suggests that more melanic pigeons have a higher ability to store some metals in their feathers compared with their paler counterparts, which could explain their higher success in urbanized areas. Overall, this work suggests that trace metal pollution may exert new selective forces favouring more melanic phenotypes in polluted environments.


Subject(s)
Columbidae/physiology , Environmental Pollutants/metabolism , Lead/metabolism , Melanins/metabolism , Pigmentation , Zinc/metabolism , Adaptation, Biological , Animals , Female , Male , Paris , Spectrophotometry, Atomic
8.
Bull Environ Contam Toxicol ; 92(2): 208-12, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24322059

ABSTRACT

Human activities often generate or increase concentration of chemical compounds including pesticides, hydrocarbons and metals that can potentially affect ecological interactions. We found that elevated levels of zinc in pigeon feathers were associated with both low prevalence of Chlamydiaceae (ornithosis disease) and low intensity of blood pathogens (Haemosporidian parasites). In contrast, high levels of lead in pigeon feathers were associated with high blood pathogens intensities. Our results suggest that metals linked to human activities in cities such as zinc and lead may play a significant role in the ecology of host-parasite interactions and could potentially affect the epidemiology of diseases in the urban environment.


Subject(s)
Columbidae/physiology , Environmental Pollutants/toxicity , Metals/toxicity , Animals , Cities , Columbidae/parasitology , Environmental Monitoring , Feathers/metabolism , Host-Parasite Interactions/drug effects
9.
Oecologia ; 173(3): 1089-99, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23685880

ABSTRACT

Urbanization is a major challenge for biodiversity conservation, yet the evolutionary processes taking place in urbanized areas remain poorly known. Human activities in cities set new selective forces in motion which need to be investigated to predict the evolutionary responses of animal species living in urban areas. In this study, we investigated the role of urbanization and parasites in the maintenance of melanin-based color polymorphism in the feral pigeon Columba livia. Using a correlative approach, we tested whether differently colored genotypes displayed alternative phenotypic responses to urbanization, by comparing body condition, blood parasite prevalence and parasite load between colored morphs along an urbanization gradient. Body condition did not vary with urbanization, but paler individuals had a higher body condition than darker individuals. Moreover, paler morphs were less often parasitized than darker morphs in moderately urbanized habitats, but their parasite prevalence increased with urbanization. In contrast, darker morphs had similar parasite prevalence along the urbanization gradient. This suggests that paler morphs did better than darker morphs in moderately urbanized environments but were negatively affected by increasing urbanization, while darker morphs performed equally in all environments. Thus, differently colored individuals were distributed non-randomly across the urban habitat and suffered different parasite risk according to their location (a gene-by-environment interaction). This suggests that melanin-based coloration might reflect alternative strategies to cope with urbanization via different exposure or susceptibility to parasites. Spatial variability of parasite pressures linked with urbanization may, thus, play a central role in the maintenance of plumage color polymorphism in this urban species.


Subject(s)
Bird Diseases/epidemiology , Bird Diseases/parasitology , Columbidae , Haemosporida , Pigmentation/genetics , Protozoan Infections, Animal/epidemiology , Age Factors , Animals , Body Constitution/physiology , Body Weights and Measures , Linear Models , Melanins/analysis , Paris/epidemiology , Pigmentation/physiology , Urbanization
10.
J Fish Biol ; 81(1): 308-13, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22747820

ABSTRACT

The Indo-Pacific mud sleeper Butis koilomatodon (Eleotridae) is recorded for the first time in the south-western Atlantic Ocean, based on 23 specimens caught at seven localities along the northern, north-eastern, eastern and south-eastern Brazilian coast. The occurrence of males and females in different ontogenetic stages indicates that this exotic mud sleeper breeds there. This invasive species has the potential to compete for food and microhabitat with several native gobies and an endemic blenny that dwell in estuaries and mangroves, besides preying on native fishes and crustaceans.


Subject(s)
Introduced Species , Perciformes , Animals , Atlantic Ocean , Brazil , Conservation of Natural Resources , Female , Geography , Male
11.
Environ Microbiol ; 13(12): 3186-93, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21933318

ABSTRACT

Chlamydiaceae are obligate intracellular Gram-negative bacteria found all over the world and known to cause various forms of disease in animals and humans. Urban pigeons are known to be an important reservoir of Chlamydia psittaci, the agent of human psittacosis. In this study, we examined the influence of pigeon houses used to regulate pigeon populations and of melanin-based coloration on several epidemiological parameters of Chlamydiaceae in 708 urban pigeons in Paris. We also identified species and genotypes of Chlamydiaceae present in Parisian populations. First, our results revealed that pigeons roosting and breeding in pigeon houses were equally infected by Chlamydiaceae as those that did not. Second, we found that dark melanic pigeons excreted more Chlamydiaceae than pale melanic ones. Finally, species and strain diversities were very low: all samples were of C. psittaci genotype B. Nevertheless, two atypical Chlamydiaceae were identified based on 16S rRNA and ompA sequences. Our study thus highlights the importance of considering environmental and host phenotype when investigating the epidemiology of infectious diseases.


Subject(s)
Chlamydophila psittaci/genetics , Cities , Columbidae/microbiology , Psittacosis/veterinary , Animals , Antibodies, Bacterial/blood , Chlamydophila psittaci/classification , Chlamydophila psittaci/pathogenicity , Cloaca/microbiology , Columbidae/physiology , Genotype , Housing, Animal , Paris/epidemiology , Phenotype , Pigmentation , Prevalence , Psittacosis/epidemiology , RNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics
12.
J Evol Biol ; 22(11): 2348-53, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19796085

ABSTRACT

When exposed to parasites, hosts often mount energetically expensive immune responses, and this may alter resource allocation between competing life history traits including other components of the immune system. Here, we investigated whether a humoral immune challenge towards a vaccine reduces or enhances the cutaneous immune responses towards an injection of lipopolysaccharid (LPS, innate immunity) and phytohaemagglutinin (PHA, T-cell immunity) in nestling tawny owls in interaction with the degree of plumage melanin-based coloration. The humoral immune challenge enhanced the response to LPS similarly in differently coloured nestlings. In contrast, the same humoral immune challenge enhanced immune response to PHA in dark reddish melanic nestlings while reducing it in pale reddish melanic nestlings. Our results highlight that both antagonistic and synergistic interactions can take place among branches of immune system, and that the sign and magnitude of these interactions can vary with immune responses involved and the degree of melanin-based coloration.


Subject(s)
Color , Feathers/metabolism , Immunity, Humoral/physiology , Immunity, Innate/physiology , Lipopolysaccharides/pharmacology , Melanins/metabolism , Phytohemagglutinins/pharmacology , Strigiformes/immunology , Animals , Immunity, Humoral/drug effects , Immunity, Innate/drug effects , Strigiformes/metabolism , Vaccines/pharmacology
13.
Mar Biol ; 156(4): 679-687, 2009.
Article in English | MEDLINE | ID: mdl-32921818

ABSTRACT

We tested whether vicariance or dispersal was the likely source of speciation in the genus Clepticus by evaluating the evolutionary timing of the effect of the mid-Atlantic barrier, which separates C. brasiliensis and C. africanus, and the Amazon barrier, which separates C. parrae and C brasiliensis. Genetic data from three mitochondrial genes and one nuclear gene were used. Mitochondrial genes separated Clepticus into three well supported clades corresponding to the three recognized allopatric morpho-species. All analyses provided consistent support for an initial separation (~9.68 to 1.86 mya; 4.84% sequence divergence) of the Caribbean and South Atlantic lineages, followed by a much more recent divergence (~ 0.60 to 0.12 mya; 0.3% sequence divergence) of the Brazilian and African sister morpho-species. Both these phylogenetic events occurred well after the formation of the two barriers that currently separate those three allopatric populations. The planktonic larval duration of these species (35-49 days) and coastal pelagic habits may have facilitated dispersal by this genus across those dispersal barriers after they formed.

14.
J Evol Biol ; 20(3): 874-80, 2007 May.
Article in English | MEDLINE | ID: mdl-17465898

ABSTRACT

Mothers can improve the quality of their offspring by increasing the level of certain components in their eggs. To examine whether or not mothers increase deposition of such components in eggs as a function of food availability, we food-supplemented black-legged kittiwake females (Rissa tridactyla) before and during egg laying and compared deposition of androgens and antibodies into eggs of first and experimentally induced replacement clutches. Food-supplemented females transferred lower amounts of androgens and antibodies into eggs of induced replacement clutches than did non-food-supplemented mothers, whereas first clutches presented no differences between treatments. Our results suggest that when females are in lower condition, they transfer more androgens and antibodies into eggs to facilitate chick development despite potential long-term costs for juveniles. Females in prime condition may avoid these potential long-term costs because they can provide their chicks with more and higher quality resources.


Subject(s)
Androgens/metabolism , Antibodies/metabolism , Charadriiformes/physiology , Feeding Behavior , Ovum/metabolism , Animals , Charadriiformes/metabolism , Clutch Size , Female , Maternal Behavior , Nesting Behavior
15.
Proc Biol Sci ; 268(1467): 647-50, 2001 Mar 22.
Article in English | MEDLINE | ID: mdl-11297183

ABSTRACT

Mothers are predicted to invest in their offspring depending on the quality of their mate, their opportunity to invest in future reproduction and the characteristics of the habitat in which their offspring will be born. Recent studies have suggested a transfer of maternal immunity to offspring as an induced response to the local presence of parasites in the environment, but evidence has been indirect. Here, we show the presence of antibodies against the Lyme disease agent Borrelia burgdorferi sensu lato, a spirochaete transmitted by the seabird tick Ixodes uriae, in the eggs of kittiwakes Rissa tridactyla. We report higher prevalence of antibodies against Borrelia in eggs from breeding areas with higher prevalence and abundance of ticks. Further, high repeatabilities of antibody-positive eggs within clutches and between first and replacement clutches show that, within a breeding season, females differ consistently with respect to the expression of this induced maternal response. Our results suggest that mothers can alter investment in their young depending on local conditions. Such maternal effects clearly have implications for the ecology and evolution of host-parasite interactions.


Subject(s)
Bird Diseases/parasitology , Birds/immunology , Birds/parasitology , Borrelia burgdorferi Group/immunology , Lyme Disease/veterinary , Tick Infestations/veterinary , Animals , Bird Diseases/immunology , Bird Diseases/microbiology , Birds/microbiology , Female , Humans , Immunity , Ixodes/microbiology , Lyme Disease/immunology , Ovum/immunology , Ovum/microbiology , Regression Analysis
16.
Arch Mal Coeur Vaiss ; 89(4): 431-4, 1996 Apr.
Article in French | MEDLINE | ID: mdl-8763002

ABSTRACT

The diagnosis of vasovagal malaise or syncope, suspected from the clinical history, may be confirmed by the tilt test. The aim of this study was to assess the effects of age on the results of this test in 346 patients who had unexplained malaise or syncope. Thirty-one patients were 7 to 19 years of age (group I), 59 were 20 to 40 (group II), 72 were 41 to 60 (group III) and 184 were 61 to 85 years old (group IV). The patients were maintained in the dorsal decubitus position for 20 minutes and then raised to 70 degrees until a malaise was observed or for a maximum of 40 minutes. The malaise or syncope was reproduced by the tilt test in 135 cases (39%). The number of positive responses was comparable in group I, II, III and IV (45, 42, 32 and 40%, respectively). The time before the malaise occurred was also similar in the four groups (17, 19, 15 and 20 minutes, respectively). Two responses to the tilt test characterised the different age groups: the greater number of malaises occurring independently of a drop in blood pressure or change in heart rate ("psychiatric" syncope) in group II compared with groups I, III and IV (40% versus 7, 9 and 9.5%); the higher frequency of pure vasodepressive forms in group IV compared with groups I, II and III (66% versus 28.5, 32 and 39%). In conclusion, the probability of a positive tilt test does not change with age. The mechanisms of the symptoms produced is the only difference observed with age.


Subject(s)
Syncope/diagnosis , Tilt-Table Test , Adolescent , Adult , Aged , Aged, 80 and over , Aging/physiology , Arrhythmias, Cardiac/complications , Child , Female , Hemodynamics , Humans , Male , Middle Aged , Psychophysiologic Disorders/complications , Reproducibility of Results , Sympathetic Nervous System/physiopathology , Syncope/etiology , Syncope/physiopathology , Tilt-Table Test/methods , Time Factors
17.
J Chir (Paris) ; 125(6-7): 416-8, 1988.
Article in French | MEDLINE | ID: mdl-3209635

ABSTRACT

Results of 334 appendectomies carried out through the umbilical orifice are reviewed. Failures of treatment and complications of the method are reported while emphasizing that only 4 major complications occurred. When compared with the classical incision of right iliac fossa this procedure does not appear to provoke more risks and presents obvious esthetic advantages.


Subject(s)
Appendectomy/methods , Hernia, Umbilical/surgery , Umbilicus/surgery , Abscess/etiology , Adolescent , Adult , Child , Child, Preschool , Female , Humans , Male , Martinique , Middle Aged , Postoperative Period
19.
Invest Ophthalmol Vis Sci ; 16(8): 757-60, 1977 Aug.
Article in English | MEDLINE | ID: mdl-328446

ABSTRACT

Antinuclear antibodies (ANA) were examined in the sera of 28 patients with chronic open angle glaucoma (COAG) and 24 normal volunteers by an immunoperoxidase technique. Unlike the results of a previous report, no significant difference in titers was found between the two groups. A highly objective radioimmunoassay for DNA antibody was also employed, giving similar results. The increased incidence of ANA at low dilutions in both COAG and normal groups in this study and its absence when measured by radioimmunoassay suggest that positive ANA reactions at such low dilutions are the result of nonspecific binding. The lack of demonstrable differences from normal in ANA- or DNA-binding antibody does not support the results of earlier studies suggesting a humoral immune or autoimmune mechanism in COAG.


Subject(s)
Antibodies, Antinuclear/analysis , DNA/immunology , Glaucoma/immunology , Antibodies/analysis , Chronic Disease , Humans , Immunoenzyme Techniques , Radioimmunoassay
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