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1.
Mol Ecol ; 26(20): 5594-5602, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28805337

RESUMO

Pheomelanin contributes to the pigmentation phenotype of animals by producing orange and light brown colours in the integument. However, pheomelanin synthesis in melanocytes requires consumption of glutathione (GSH), the most important intracellular antioxidant. Therefore, a genetic control favouring the production of large amounts of pheomelanin for pigmentation may lead to physiological costs under environmental conditions that promote oxidative stress. We investigated this possibility in the context of breeding coloniality, a reproductive strategy that may affect oxidative stress. We found in lesser kestrel Falco naumanni nestlings that the GSH:GSSG ratio, which decreases with systemic oxidative stress, increased with the size of the colony where they were reared, but the expression in feather melanocytes of five genes involved in pheomelanin synthesis (Slc7a11, Slc45a2, CTNS, MC1R and AGRP) did not vary with colony size. The antioxidant capacity (TEAC) of lesser kestrel nestlings also increased with colony size, but in a manner that depended on Slc7a11 expression and not on the expression of the other genes. Thus, antioxidant capacity increased with colony size only in nestlings least expressing Slc7a11, a gene with a known role in mediating cysteine (a constituent amino acid of GSH) consumption for pheomelanin production. The main predictor of the intensity of pheomelanin-based feather colour was Slc45a2 expression followed in importance by Slc7a11 expression, hence suggesting that the genetic regulation of the pigmentation phenotype mediated by Slc7a11 and a lack of epigenetic lability in this gene limits birds from benefiting from the physiological benefits of coloniality.


Assuntos
Falconiformes/genética , Melaninas/genética , Pigmentação/genética , Animais , Antioxidantes/fisiologia , Plumas , Feminino , Glutationa/fisiologia , Masculino , Melanócitos/fisiologia , Modelos Genéticos , Estresse Oxidativo , Fatores Sexuais , Pele , Ácido Úrico/sangue
2.
Ecotoxicol Environ Saf ; 143: 143-150, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28528317

RESUMO

Lead is considered a highly toxic contaminant with important impacts to bird wildlife. Griffon vultures (Gyps fulvus) are a sensitive indicator of the level of environmental contamination due to their position at the top of the food chain and their dependence on human activities. The aim of this study was to assess susceptibility to lead intoxication in Griffon vultures admitted to Wildlife Rehabilitation Centers (WRC), measuring blood lead levels and determining if blood lead concentrations are related to clinical signs, hematological, biochemical or radiographic findings. Also, the influence of age, gender, body condition, season and primary cause of admission were evaluated. This study was realized in all Griffon vultures admitted during a period of one year in the Rehabilitation Center GREFA. Blood lead levels are measured by using anodic stripping voltammetry. In Griffon vultures, we observed that 26% of the analyzed birds presented lead levels above 20µg/dL with 74% below 20µg/dL ([Pb]<20 =9.34±5.60µg/dL). In our study, statistically significant differences were found for lead according to sex, season of admission to the center and body condition. A negative correlation was found between levels of metal and hematocrit. No association was found between clinical signs and blood lead levels in Griffon vultures, except for digestive signs as stasis and weight loss. On numerous occasions, the intoxication in this specie is related to ingestion of lead ammunition; however, we have not detected radiographic lead in our vultures. Compared with other studies, we generally found low levels of lead in blood of Griffon vultures but the blood of all birds admitted to WRC presented detectable lead concentrations. This species apparently presents a higher sensibility to the toxic effects of this metal than that described by other authors. It have been observed that there is some evidence that suggests that subclinical levels of lead could be related with a predisposition to injury or diseases, even though these birds might be admitted for other causes. The detection of levels of blood lead in animals that are admitted to a recovery center will give valuable information which could be used to monitor spatial and temporal variations and provide a clearer picture of temporal levels of this contaminant in this emblematic avian specie.


Assuntos
Poluentes Ambientais/sangue , Falconiformes/sangue , Chumbo/sangue , Animais , Monitoramento Ambiental , Feminino , Masculino , Espanha
3.
Sci Rep ; 12(1): 16188, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36171410

RESUMO

The estimation of the post-mortem interval is crucial to accurately provide bird collision rates against manmade infrastructures. Standard methodologies recommend initially clearing all carcasses to ensure that subsequent collisions can be attributed to known time intervals. In this study, we propose a more cost-efficient approach aiming to link the decomposition stages as unequivocally as possible to the most likely time elapsed since death. Factors influencing the decomposition stages of bird carcasses were evaluated by means of two experiments. Firstly, we examined carcasses of large birds in three seasons differing in temperature, sun radiation and humidity: summer, autumn and spring. Secondly, we tested the influence of body mass in the same season (spring) using small, medium-sized and large bird carcasses. Results showed that the decomposition score increased monotonically with time, attaining the highest magnitude effect. A carcass with a decomposition score ≥ 4 (skeletal reduction) was in the field for ≥ 15 days, whereas a carcass with a score < 3 (fresh or emphysematous) was exposed < 3 days. Decomposition scores were higher in summer and did not differ among carcass sizes. This study provides an alternative protocol to estimate the post-mortem interval in wild birds in studies in search of bird fatalities.


Assuntos
Aves , Mudanças Depois da Morte , Animais , Autopsia , Cadáver , Estações do Ano , Temperatura
4.
Animals (Basel) ; 12(19)2022 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-36230455

RESUMO

The presence of AMR bacteria in the human-animal-environmental interface is a clear example of the One Health medicine. Several studies evidence the presence of resistant bacteria in wildlife, which can be used as a good indicator of anthropization level on the ecosystem. The fast increase in AMR in the environment in the last decade has been led by several factors as globalization and migration. Migratory birds can travel hundreds of kilometers and disseminate pathogens and AMR through different regions or even continents. The aim of this study was to compare the level of AMR in three migratory bird species: Ciconia ciconia, Larus fuscus and Chroicocephalus ridibundus. For this purpose, commensal Escherichia coli has been considered a useful indicator for AMR studies. After E. coli isolation from individual cloacal swabs, antimicrobial susceptibility tests were performed by the disk-diffusion method, including 17 different antibiotics. A total of 63.2% of gulls had resistant strains, in contrast to 31.6% of white storks. Out of all the resistant strains, 38.9% were considered multi-drug resistant (50% of white storks and 30% of seagulls). The antibiotic classes with the highest rate of AMR were betalactamics, quinolones and tetracyclines, the most commonly used antibiotic in human and veterinary medicine in Spain.

5.
Comp Immunol Microbiol Infect Dis ; 79: 101712, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34688167

RESUMO

Wild birds have been identified as a relevant reservoir of Campylobacter spp., therefore, a potential source of infection in humans and domestic animals. The objective of this study was to determine the occurrence of Campylobacter spp. on birds of prey in Spain. In addition, antibiotic resistance profiles of the isolates were evaluated. A total of 689 specimens of 28 raptor species were analyzed, with a resulting individual prevalence of 7.5%. C. jejuni was the most frequently isolated species (88.5%), followed by C. coli and C. lari (3.8% each). The occurrence of Campylobacter was significantly higher (p < 0.05) in nocturnal birds of prey (15.3%), in spring season (12.2%) and in carnivorous species (9.4%). Isolates displayed a remarkable resistance to nalidixic acid (69.9%), ciprofloxacin (69.9%), and tetracycline (55.6%), and a low resistance to streptomycin (6.7%). Our findings highlight the importance of birds of prey as reservoirs of Campylobacter strains and their significant role as carriers of antimicrobial resistance.


Assuntos
Infecções por Campylobacter , Campylobacter coli , Campylobacter jejuni , Campylobacter , Aves Predatórias , Animais , Antibacterianos/farmacologia , Aves , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/veterinária , Farmacorresistência Bacteriana , Prevalência , Espanha/epidemiologia
6.
Prev Vet Med ; 175: 104875, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31896502

RESUMO

Pododermatitis is a chronic and progressive bacterial infectious disease of birds´ footpads, especially associated with captivity, which could represent an important problem in wildlife rehabilitation centres, delaying the release of the birds to the environment and harming their conservation. The objectives of the present study were i) to estimate the incidence rate of pododermatitis, ii) to analyse the influence of environmental, physiological, and pathological factors which may influence the onset of the infection in raptors after their admission to a rehabilitation centre, and iii) to follow up the evolution and macroscopic characteristics of the lesion. An observational retrospective study was carried out on clinical cases of raptors (n = 2004) admitted in a rehabilitation centre in central Spain from 2009 to 2015. The proportion of pododermatitis was 6.9%, with an incidence density of 6.8 cases/100 bird-years at risk. Our results showed that the disease was more likely to occur in birds staying longer (P < 0.001). According to Cox analysis, the variables 'raptor family' (P < 0.001) and 'age' (P = 0.002) may have significant effects on pododermatitis development. Raptors from the Falconidae and Strigidae families were less likely to develop pododermatitis than those from the Accipitridae family, with a hazard ratio (HR) of 0.31 and 0.13, respectively. Regarding age, fully feathered raptors had a three-fold higher risk of having pododermatitis than non-fully feathered birds. Survival analysis of time of pododermatitis development revealed significant differences associated with the variables 'raptor family' (P < 0.03); 'age' (P < 0.001) and 'cause of admission' (P = 0.001). Duration of the pathology (P < 0.05) and lesion location (P < 0.001) seemed to be phylogenetic dependent. Injuries were primarily located in the toes area or the whole footpad of birds belonging to the Accipitridae or Falconidae families, respectively (P = 0.003).


Assuntos
Doenças das Aves/epidemiologia , Dermatite/veterinária , Doenças do Pé/veterinária , Aves Predatórias , Animais , Doenças das Aves/etiologia , Dermatite/epidemiologia , Dermatite/etiologia , Doenças do Pé/epidemiologia , Doenças do Pé/etiologia , Incidência , Espanha/epidemiologia
7.
Int J Rheum Dis ; 20(10): 1541-1550, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28425178

RESUMO

AIM: Sleep problems are a common complaint in systemic lupus erythematosus (SLE) patients. We analyzed sleep quality with subjective and objective measures in a sample with SLE and its possible relationships with the main manifestations of the disease. METHODS: Twenty-one women with SLE and 20 healthy women participated in the study. All participants were evaluated with actigraphy for a week and they completed self-report instruments of sleep quality, quality of life, fatigue, anxiety, depression and perceived stress. Comparison analyses between the two groups were done using Chi-square and Student's t-tests. The association between sleep quality and the remaining variables was explored using Pearson correlation coefficients. RESULTS: SLE patients had higher fragmentation index in the actigraphic analysis and a perception of poorer sleep quality, more fatigue, anxiety and depression than the control group. Bivariate analyses showed that the perception of more sleep disturbance and daytime dysfunction was associated with a lower health-related quality of life, more fatigue, emotional discomfort and more perceived stress. Also, the fragmentation index in the actigraphy was significantly related to the perception of poorer quality of sleep. CONCLUSION: SLE women had a poorer sleep quality (objective and subjective). These alterations could play a modulatory role in clinical and psychological manifestations of the disease and affect the quality of life in this population. More research is needed to clarify these relations and to determine the potential benefits of interventions directed to improve sleep in the clinical managing of the patients with SLE.


Assuntos
Ansiedade/etiologia , Depressão/etiologia , Lúpus Eritematoso Sistêmico/complicações , Saúde Mental , Transtornos do Sono-Vigília/etiologia , Sono , Estresse Psicológico/etiologia , Actigrafia , Adolescente , Adulto , Idoso , Ansiedade/diagnóstico , Ansiedade/psicologia , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Efeitos Psicossociais da Doença , Depressão/diagnóstico , Depressão/psicologia , Emoções , Feminino , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/fisiopatologia , Lúpus Eritematoso Sistêmico/psicologia , Pessoa de Meia-Idade , Qualidade de Vida , Fatores de Risco , Autorrelato , Fatores Sexuais , Transtornos do Sono-Vigília/diagnóstico , Transtornos do Sono-Vigília/fisiopatologia , Estresse Psicológico/diagnóstico , Estresse Psicológico/psicologia , Adulto Jovem
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