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1.
Rev. biol. trop ; 72(1): e55265, ene.-dic. 2024. tab, graf
Article de Anglais | SaludCR, LILACS | ID: biblio-1559322

RÉSUMÉ

Abstract Introduction: The Wood Thrush is a migratory bird that has experienced dramatic declines in its populations in recent decades. This species overwinters in forest fragments with intermediate levels of habitat modification in Central America. However, more studies detailing the use of remnant forests through time are needed to elucidate the threats this species faces in the wintering grounds. Objective: To understand the effects of environmental and forest structure variables on the occupancy of Wood Thrush in Northern Costa Rica. Methods: The study area was the Área de Conservación Guanacaste (ACG), located in Northern Costa Rica, in December 2016, and during the 2018-2019 migration season. We estimated Wood Thrush occupancy and detection probability in four locations of ACG (dry forest, cloud forest, and two locations in the wet forest) using single-season occupancy models. We also estimated Wood Thrush occupancy and probability of persistence in different months in three vegetation types (open area, secondary forest, and old-growth forest) in the wet forest of ACG using a multi-season occupancy model approach. Results: Wood Thrush occupancy was best described by precipitation in the four locations of the ACG; the probability of occupancy increased with precipitation. The average occupancy of Wood Thrushes varied with vegetation type: open area with shrubs and forest edge (0.69 ± 0.09), secondary forest (0.46 ± 0.1), and old-growth forest (0.61 ± 0.1). Wood Thrush probability of persistence responded partially to changes in precipitation, with an unexpected increase in persistence when the rainfall continued decreasing in the season. Conclusion: Wood Thrush occupancy was best predicted by changes in precipitation considering a larger spatial scale. Its probability of persistence partially varied with precipitation. An increase in persistence closer to Spring migration might be explained by the start of the breeding season of resident birds, potentially reducing territorial conflicts and conserving energy before migration. The long-term protection of wet forests in Northern Costa Rica is of paramount importance for the conservation of Wood Thrushes in their wintering grounds.


Resumen Introducción: El Zorzal del Bosque es un ave migratoria que ha experimentado caídas dramáticas en sus poblaciones en las últimas décadas. Esta especie pasa el invierno en fragmentos de bosque con niveles intermedios de modificación de hábitat en Centroamérica. Sin embargo, se necesitan más estudios que detallen el uso de los bosques remanentes a lo largo del tiempo para dilucidar las amenazas que enfrenta esta especie en las zonas de invernada. Objetivo: Comprender los efectos de variables ambientales y de estructura del bosque en la ocurrencia del Zorzal del Bosque en el Norte de Costa Rica. Métodos: El área de estudio fue el Área de Conservación Guanacaste (ACG), ubicada en el Norte de Costa Rica, en diciembre de 2016, y en la temporada migratoria 2018-2019. Estimamos la ocurrencia y la probabilidad de detección del Zorzal del Bosque en cuatro ubicaciones de ACG (bosque seco, bosque nuboso y dos ubicaciones en el bosque húmedo) utilizando modelos de ocurrencia de una sola temporada. También estimamos la ocurrencia del Zorzal del Bosque y la probabilidad de persistencia en diferentes meses en tres tipos de vegetación (área abierta, bosque secundario y bosque primario) en el bosque húmedo de ACG utilizando un enfoque de modelo de ocurrencia multi-estacional. Resultados: La ocurrencia del Zorzal del Bosque estuvo mejor descrita por la precipitación en las cuatro localidades del ACG; la probabilidad de ocurrencia aumentó con las precipitaciones. La ocurrencia media de zorzales varió con el tipo de vegetación: área abierta con arbustos y borde de bosque (0.69 ± 0.09), bosque secundario (0.46 ± 0.1) y bosque primario (0.61 ± 0.1). La probabilidad de persistencia del zorzal respondió parcialmente a cambios en la precipitación, con un aumento inesperado en la persistencia cuando las precipitaciones continuaron disminuyendo en la temporada. Conclusión: La ocurrecia del Zorzal del Bosque varió con la precipitación considerando una escala espacial mayor. Su probabilidad de persistencia varió parcialmente con la precipitación. Un aumento en la persistencia más cerca de la migración de primavera podría explicarse por el inicio de la temporada de reproducción de las aves residentes, lo que podría reducir los conflictos territoriales y conservar energía antes de la migración. La protección a largo plazo de los bosques húmedos en el norte de Costa Rica es de suma importancia para la conservación de los Zorzales del Bosque en sus zonas de invernada.


Sujet(s)
Animaux , Migration animale , Passeriformes , Saisons , Costa Rica
2.
Talanta ; 279: 126639, 2024 Jul 31.
Article de Anglais | MEDLINE | ID: mdl-39094531

RÉSUMÉ

In this paper, an ultra-small-sized CuOx/GDYO nanozyme in situ grown on ITO glass was rationally synthesized from mixed precursors of graphdiyne oxide (GDYO) and copper based infinite coordination polymer (Cu-ICP, consisting of Cu ions and two organic ligands 3,5-di-tert-butylcatechol and 1,4-bis(imidazole-1-ylmethyl)benzene) via mild and simple electrochemical strategy. On one hand, the preferential electro-reduction of Cu-ICP enabled the formation of ultra-small CuOx with Cu(I) as the main component and avoided the loss of oxygen-containing functional groups and defects on the surface of GDYO; on the other hand, GDYO can also serve as electroless reductive species to facilitate the electrochemical deposition of CuOx and turn itself to a higher oxidation state with more exposed functional groups and defects. This one-stone-two-birds electrochemical strategy empowered CuOx/GDYO nanozyme with superior peroxidase-mimicking activity and robust anchoring stability on ITO glass, thus enabled further exploration of the portable device with availability for point-of-use applications. Based on the organophosphorus pesticides (OPs) blocked acetylcholinesterase (AChE) activity, the competitive redox reaction was regulated to initiate the chromogenic reaction of 3,3',5,5'-tetramethylbenzidine (TMB) catalyzed by CuOx/GDYO peroxidase-like nanozyme, which laid out a foundation for the detection of OPs (with chlorpyrifos as an example). With a detection of limit low to 0.57 nM, the OPs residues during agricultural production can be directly monitored by the portable device we developed.

4.
J Adv Vet Anim Res ; 11(2): 339-348, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-39101078

RÉSUMÉ

Objective: In the present research work, we examined the dietary Moringa oleifera effect on gut health and growth traits in chickens. Materials and Methods: There were 280 chicks (day old) that were weighted and allotted uniformly in seven groupings, each containing eight replicates (n = 5). Birds were supplemented with M. oleifera leaf extract (MLE) and seed extract (MSE) for 35 days. Group I was the control (fed merely basal diets), while Group II received 0.8% MLE, Group III was given 0.8% MSE, Group IV was given 1.2% MLE, Group V was given 1.2% MSE, Group VI was given 0.8% MLE + 0.8% MSE, and Group VII was given 1.2% MLE + 1.2% MSE. At the end of the fifth week, two chickens were selected from each replica, and samples (small intestine and ileal ingesta) were collected. Results: The chicken diet with MLE and MSE supplements saw significant improvement (p < 0.05) in both feed conversion ratio (FCR) and body weight gain (BWG). In the small intestine (duodenal, jejunal, and ileal), dietary MLE and MSE supplements significantly increased (p < 0.05) the surface area of the villus and the ratio of their height/crypt depth in comparison to the control group. The MLE and MSE supplements significantly increased (p < 0.05) the total goblet cell counts in the small intestine. The Lactobacillus spp. count was significantly improved (p < 0.05) and reduced (p < 0.05) in Escherichia coli counts when the bird diet was supplemented with MLE (0.8%) and MSE (0.8%). Conclusion: Results indicated that M. oleifera leaf and seed extract diet improved the growth trait and gut health in chickens.

5.
Ecol Appl ; : e3010, 2024 Jul 08.
Article de Anglais | MEDLINE | ID: mdl-38978282

RÉSUMÉ

Since 2014, highly pathogenic avian influenza (HPAI) H5 viruses of clade 2.3.4.4 have been dominating the outbreaks across Europe, causing massive deaths among poultry and wild birds. However, the factors shaping these broad-scale outbreak patterns, especially those related to waterbird community composition, remain unclear. In particular, we do not know whether these risk factors differ from those of other H5 clades. Addressing this knowledge gap is important for predicting and preventing future HPAI outbreaks. Using extensive waterbird survey datasets from about 6883 sites, we here explored the effect of waterbird community composition on HPAI H5Nx (clade 2.3.4.4) spatial patterns in the 2016/2017 and 2020/2021 epidemics in Europe, and compared it with the 2005/2006 HPAI H5N1 (clade 2.2) epidemic. We showed that HPAI H5 occurrences in wild birds in the three epidemics were strongly associated with very similar waterbird community attributes, which suggested that, in nature, similar interspecific transmission processes operate between the HPAI H5 subtypes or clades. Importantly, community phylogenetic diversity consistently showed a negative association with H5 occurrence in all three epidemics, suggesting a dilution effect of phylogenetic diversity. In contrast, waterbird community variables showed much weaker associations with HPAI H5Nx occurrence in poultry. Our results demonstrate that models based on previous epidemics can predict future HPAI H5 patterns in wild birds, implying that it is important to include waterbird community factors in future HPAI studies to predict outbreaks and improve surveillance activities.

6.
J Anim Ecol ; 2024 Jul 01.
Article de Anglais | MEDLINE | ID: mdl-38946701

RÉSUMÉ

Among migratory vertebrates, high levels of fidelity to non-breeding sites during adulthood are common. If occupied sites vary in quality, strong site fidelity can have profound consequences for individual fitness and population demography. Given the prevalence of adult site fidelity, the regions of the non-breeding range to which juveniles first migrate, and the scale of any subsequent movements, are likely to be pivotal in shaping distributions and demographic processes across population ranges. However, inherent difficulties in tracking migratory individuals through early life mean that opportunities to quantify juvenile settlement and movements across non-breeding ranges, and the mechanisms involved, are extremely rare. Through long-term, range-wide resightings of hundreds of colour-marked individuals from their first migration to adulthood and the application of state-space models, we quantify levels of juvenile and adult regional-scale movements and distances at different life stages across the whole non-breeding distribution range in a migratory shorebird, the Black-tailed Godwit (Limosa limosa islandica). We show that the probability of individuals changing non-breeding regions (seven historical wintering regions spanning the Western Europe range) at all ages is very low (mean movement probability = 10.9% from first to subsequent winter, and 8.3% from first adult winter to later winters). Movement between regions was also low between autumn and winter of the same year for both juveniles (mean movement probability = 17.0%) and adults (10.4%). The great majority of non-breeding movements from the first autumn to adulthood were within regions and less than 100 km. The scarcity of regional-scale non-breeding movements from the first autumn to adulthood means that the factors influencing where juveniles settle will be key determinants of non-breeding distributions and of the rate and direction of changes in distributions.

7.
J Chem Ecol ; 2024 Jun 29.
Article de Anglais | MEDLINE | ID: mdl-38949747

RÉSUMÉ

Plant responses to damage by insectivorous herbivores are well-documented in mature leaves. The resulting herbivore-induced plant volatiles (HIPVs) protect the plant by attracting carnivorous arthropods and even some insectivorous vertebrates, to parasitize or consume the plant invaders. However, very little is known about plant production of HIPVs in developing buds, particularly when herbivorous insects are too small to be considered a prey item. It is additionally unclear whether plants respond differently to generalist and specialist chewing insects that overlap in distribution. Therefore, we compared HIPV production of Downy oak (Quercus pubescens Willd.) buds infested with freshly hatched caterpillars of Tortrix viridana (specialist) and Operophtera brumata (generalist), against uninfested buds. Of the compounds identified in both years of the experiment, we found that (Z)-hex-3-enyl acetate, (E)-ß-ocimene, acetophenone, linalool, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), methyl salicylate, α-copaene, α-humulene, (E)-caryophyllene, and (E,E)-α-farnesene appeared to be higher in infested buds compared to controls. We found no difference in HIPV production between the specialist and the generalist herbivores. Production of HIPVs was also associated with leaf damage, with higher HIPV production in more severely attacked buds. Thus, our study shows that oak trees already start responding to insect herbivory before leaves are developed, by producing compounds similar to those found in damaged mature leaves. Future work should focus on how Downy oak may benefit from initiating alarm cues at a time when carnivorous arthropods and insectivorous vertebrates are unable to use herbivorous insects as host or food.

8.
Pathogens ; 13(7)2024 Jul 08.
Article de Anglais | MEDLINE | ID: mdl-39057798

RÉSUMÉ

A quantitative microbial risk assessment model was developed to estimate the probability that the aerosolization of fecal droppings from wild birds in the vicinity of poultry farms would result in the infection of indoor-housed poultry with highly pathogenic avian influenza virus (HPAIv) in the Netherlands. Model input parameters were sourced from the scientific literature and experimental data. The availability of data was diverse across input parameters, and especially parameters on the aerosolization of fecal droppings, survival of HPAIv and dispersal of aerosols were uncertain. Model results indicated that the daily probability of infection of a single poultry farm is very low, with a median value of 7.5 × 10-9. Accounting for the total number of poultry farms and the length of the bird-flu season, the median overall probability of at least one HPAIv-infected poultry farm during the bird-flu season is 2.2 × 10-3 (approximately once every 455 years). This is an overall estimate, averaged over different farm types, virus strains and wild bird species, and results indicate that uncertainty is relatively high. Based on these model results, we conclude that it is unlikely that this introduction route plays an important role in the occurrence of HPAIv outbreaks in indoor-housed poultry.

9.
Euro Surveill ; 29(30)2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39056196

RÉSUMÉ

This report describes an unusual surge of West Nile fever in Israel in June 2024, during which 125 cases were diagnosed, compared with 4 cases on average during June in previous years (2014-23). Of the cases, 64 (62.1%) had neuroinvasive disease and 12 (9.6%) died; the 2024 case fatality rate was not significantly elevated vs the average rate in 2014-23. The early rise could be related to a temperature increase in spring and early summer of 2024.


Sujet(s)
Saisons , Fièvre à virus West Nile , Virus du Nil occidental , Israël/épidémiologie , Humains , Fièvre à virus West Nile/épidémiologie , Fièvre à virus West Nile/diagnostic , Fièvre à virus West Nile/mortalité , Virus du Nil occidental/isolement et purification , Mâle , Femelle , Épidémies de maladies , Adulte d'âge moyen , Adulte , Incidence , Sujet âgé , Surveillance de la population
10.
Parasitol Int ; 103: 102936, 2024 Jul 24.
Article de Anglais | MEDLINE | ID: mdl-39059483

RÉSUMÉ

Spinetails are a suboscine passerines of the genus Synallaxis Vieillot, 1818 which have great interest for ornithology, given the wide diversity of 37 species that are distributed throughout the Neotropical region. Despite this wide diversity and distribution, Synallaxis spp. have never been recorded as hosts of coccidian parasites. In this context, the current study describes a new species of Isospora Schneider, 1881 from rufous-capped spinetails Synallaxis ruficapilla Vieillot, 1819 captured in the Itatiaia National Park, which is a federal conservation unit in Southeastern Brazil. The oocysts of Isospora pichororei Genovez-Oliveira & Berto n. sp. are subspheroidal to ovoidal, measuring on average 25 by 21 µm. Micropyle is present, but discrete. Oocyst residuum absent, but one or two polar granules are present. Sporocysts are ellipsoidal with slightly pointed posterior end, measuring on average 17 by 10 µm. Stieda and sub-Stieda bodies are present. Sporocyst residuum is clustered among the vermiform sporozoites, which have striations, refractile bodies and nucleus. This morphology was different from the other Isospora spp. recorded in the host family Furnariidae. Molecular identification was targeted by the amplification and sequencing of a locus of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. This sequence had the highest similarity of 99.5% with a sequence deposited for Isospora oliveirai Ortúzar-Ferreira & Berto, 2020, which is a coccidian species that parasitizes suboscine tityrids Schiffornis virescens (Lafresnaye, 1838), also in the Itatiaia National Park. Phylogenetic analysis grouped some species in subclades, including I. pichororei with I. oliveirai; however, it was inconclusive in an expectation of parasite-host coevolution. Finally, I. pichororei is established as new to science, being the first description from Synallaxinae and the third description from Furnariidae. Furthermore, this is the first Isospora sp. from the host family Furnariidae to have a molecular supplementation by sequencing a locus of the cox1 gene of the mitochondrial genome.

11.
Sci Rep ; 14(1): 16397, 2024 07 16.
Article de Anglais | MEDLINE | ID: mdl-39013969

RÉSUMÉ

Bird sex determination is fundamental in various ecological and biological studies, although many avian species cannot be sexed visually due to their monomorphic and/or monochromatic appearance. Thus, reliable laboratory methods for sexing are a prerequisite. Most avian nestlings lack sex-related signs, including the Eurasian pygmy owl (Glaucidium passerinum). We performed laboratory sex determination analysis of this species using blood samples of 242 juveniles and nine adults. It relied on the qPCR of the specific intron from the chromo-helicase DNA-binding protein 1 gene. We tested three primer sets, the P2/P8, 2550F/2718R, and CHD1F/CHD1R, commonly used for bird laboratory sexing. The outcomes were displayed on an agarose gel electrophoresis and a plot from melt curve analysis, which had not been previously conducted in Eurasian pygmy owls. We found that only primer set CHD1F/CHD1R proved reliable, as the only one determined sex with one and two band/s and peak/s on the electrophoresis and the melt curve plot for males and females, respectively. The other two primer pairs failed and depicted one band/peak in all specimens regardless of their sex. Therefore, we recommend performing Eurasian pygmy owls' laboratory sexing by qPCR with CHD1F/CHD1R primers only.


Sujet(s)
Amorces ADN , Détermination du sexe , Strigiformes , Animaux , Détermination du sexe/méthodes , Femelle , Mâle , Strigiformes/génétique , Amorces ADN/génétique
12.
Mar Environ Res ; 199: 106627, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38968803

RÉSUMÉ

DNA metabarcoding and stable isotope analysis have significantly advanced our understanding of marine trophic ecology, aiding systematic research on foraging habits and species conservation. In this study, we employed these methods to analyse faecal and blood samples, respectively, to compare the trophic ecology of two Red-billed Tropicbird (Phaethonaethereus; Linnaeus, 1758) colonies on Mexican islands in the Pacific. Trophic patterns among different breeding stages were also examined at both colonies. Dietary analysis reveals a preference for epipelagic fish, cephalopods, and small crustaceans, with variations between colonies and breeding stages. Isotopic values (δ15N and δ13C) align with DNA metabarcoding results, with wider niches during incubation stages. Differences in diet are linked to environmental conditions and trophic plasticity among breeding stages, influenced by changing physiological requirements and prey availability. Variations in dietary profiles reflect contrasting environmental conditions affecting local prey availability.


Sujet(s)
Codage à barres de l'ADN pour la taxonomie , Chaine alimentaire , Animaux , Isotopes du carbone/analyse , Régime alimentaire , Isotopes de l'azote/analyse , Oiseaux/physiologie , Mexique
13.
Environ Res ; 261: 119641, 2024 Jul 23.
Article de Anglais | MEDLINE | ID: mdl-39053757

RÉSUMÉ

Mercury (Hg), especially methylmercury (MeHg), is a pervasive contaminant that poses significant risks to birds occupying high trophic levels. However, we have little knowledge about the mercury exposure and its risks for birds in Poyang Lake basin, China. Therefore, during 2020-2021, we investigated MeHg concentrations in breast feathers of wintering migratory birds (n = 430 from 43 species belonging to 9 orders) in Poyang Lake Nanji Wetland and Jiangxi Nanfengmian National Nature Reserve, China. MeHg concentrations in breast feathers varied greatly by species, foraging guilds and taxonomic orders, among which the highest concentration was detected in great egret (8849 ± 5975 ng g-1 dw). Comparing with studies worldwide, high MeHg concentrations in feathers of Ardeidae from Pelecaniformes were found in this area. Moreover, herons migrating between northern and southern China had lower MeHg concentration than residents in southern China related to habitat Hg. Considering the applicability and sensitivity of the equations for the transformation of MeHg concentrations in feathers to blood-equivalent total Hg (THg) values, method CJ that the equation based on songbirds was used for the transformation of the songbirds and the equation based on seabirds for the others performed better than other three for risk assessment of bird Hg in this study. 23.1% of birds from Poyang Lake were at risk of Hg exposure based on the method CJ. Carnivorous birds from Pelecaniformes had the highest risk levels, with 37.2% categorized as no risk (≤200 ng g-1 ww), 48.9% as low risk (200-1000 ng g-1 ww), 11.1% as moderate risk (1000-3000 ng g-1 ww), 1.1% as high risk (3000-4000 ng g-1 ww), and 1.7% as severe risk (>4000 ng g-1 ww). These risks suggest long-term monitoring and further advanced studies about freshwater waterbirds Hg exposure is necessary.

15.
R Soc Open Sci ; 11(6): 1231721, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39077219

RÉSUMÉ

Urban configuration and food availability influence birds' foraging behaviour and constitute key factors for understanding how they exploit cities. Here, we conducted a field survey in the city of Madrid (Spain) from winter 2021 to autumn 2022 to understand how the common wood pigeon (Columba palumbus) exploits the food resources provided by urban parks and streets across different seasons. The proportion of observations away from parks increased during winter and spring, and the proportion of observations of wood pigeons eating on the ground was the greatest in summer. The common wood pigeon fed from 45 tree species, 60% of which were exotic ornamental species. Most tree species used as food sources coincided with those widely planted in parks, streets and avenues. The preferred trees varied throughout the year, with a greater incidence of exotic species in winter and spring. Our results show that the diversity of trees available in cities and the use of non-native plants with contrasting phenological patterns compared with the local flora are crucial elements in explaining the successful establishment of the common wood pigeon in the city.

16.
Environ Toxicol Chem ; 2024 Jul 25.
Article de Anglais | MEDLINE | ID: mdl-39051738

RÉSUMÉ

Energy content, moisture content, and energy assimilation efficiency are essential parameters in the food intake rate (FIR) and exposure calculations for bird and mammal risk assessments. The updated European Food Safety Authority guidance document on risk assessment for birds and mammals summarizes these parameters for different food items. For seed treatments, values for cereal seeds are proposed as surrogates for other crops. Oil-containing seeds are expected to have a higher energy content than cereal seeds. This would result in lower FIR and, thus, exposure from consuming such seeds. To be able to calculate reliable exposure values for risk-assessment purposes, we conducted a systematic literature review to collect information on these three parameters for oil-containing seeds (sunflower, oilseed rape, soybean, peanut, sesame, safflower, linseed [flax], white mustard, and castor bean). The search yielded 401 papers, of which 151 contained values for at least one of the parameters of the crops in focus. The overall average energy content value of oil-containing seeds was 24.25 kJ/g (n = 124, SD = 3.00), whereas that for moisture content was 6.57% (n = 296, SD = 1.15). Energy assimilation values were only available for peanut, oilseed rape, soy, linseed, and sunflower for a limited number of bird and mammal species. Mean energy assimilation efficiency for mammals was 82.69% (n = 4, SD = 1.55), whereas values for birds were 57.54% (n = 2, SD = 6.77) for Galliformes and 79.25% (n = 2, SD = 1.82) for Passeriformes. The values presented can be used to calculate appropriate FIR values for future bird and mammal risk assessments. Environ Toxicol Chem 2024;00:1-6. © 2024 The Author(s). Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

17.
Biol Open ; 2024 Jul 29.
Article de Anglais | MEDLINE | ID: mdl-39069816

RÉSUMÉ

Exposure of wildlife to anthropogenic noise is associated with disruptive effects. Research on this topic has focused on behavioural and physiological responses of animals to noise, with little work investigating links to cognitive function. Neurological processes that maintain cognitive performance can be impacted by stress and sleep disturbances. While sleep loss impairs cognitive performance in Australian magpies, it is unclear whether urban noise, which disrupts sleep, can impact cognition as well. To fill this gap, we explored how environmentally relevant urban noise affected the performance of wild-caught, city-living Australian magpies (Gymnorhina tibicen tyrannica) on a cognitive task battery including associative and reversal learning, inhibitory control, and spatial memory. Birds were housed and tested in a laboratory environment; sample sizes varied across tasks (n=7 - 9 birds). Tests were conducted over four weeks, during which all magpies were exposed to both an urban noise playback and a quiet control. Birds were presented with the entire test battery twice: following exposure to, and in the absence of, an anthropogenic noise playback; however, tests were always performed without noise (playback muted during testing). Magpies performed similarly in both treatments on all four tasks. We also found that prior experience with the associative learning task had a strong effect on performance, with birds performing better on their second round of trials. Like previous findings on Australian magpies tested on the same tasks in the wild under noisy conditions, we could not find any disruptive effects on cognitive performance in a controlled experimental laboratory setting.

18.
Front Vet Sci ; 11: 1415559, 2024.
Article de Anglais | MEDLINE | ID: mdl-39055861

RÉSUMÉ

Introduction: The increasing geographical spread of highly pathogenic avian influenza viruses (HPAIVs) is of global concern due to the underlying zoonotic and pandemic potential of the virus and its economic impact. An integrated One Health model was developed to estimate the likelihood of Avian Influenza (AI) introduction and transmission in Cuba, which will help inform and strengthen risk-based surveillance activities. Materials and methods: The spatial resolution used for the model was the smallest administrative district ("Consejo Popular"). The model was parameterised for transmission from wild birds to poultry and pigs (commercial and backyard) and then to humans. The model includes parameters such as risk factors for the introduction and transmission of AI into Cuba, animal and human population densities; contact intensity and a transmission parameter (ß). Results: Areas with a higher risk of AI transmission were identified for each species and type of production system. Some variability was observed in the distribution of areas estimated to have a higher probability of AI introduction and transmission. In particular, the south-western and eastern regions of Cuba were highlighted as areas with the highest risk of transmission. Discussion: These results are potentially useful for refining existing criteria for the selection of farms for active surveillance, which could improve the ability to detect positive cases. The model results could contribute to the design of an integrated One Health risk-based surveillance system for AI in Cuba. In addition, the model identified geographical regions of particular importance where resources could be targeted to strengthen biosecurity and early warning surveillance.

19.
Microbiol Resour Announc ; : e0032924, 2024 Jul 31.
Article de Anglais | MEDLINE | ID: mdl-39082792

RÉSUMÉ

This study reports a genome of psittaciform chaphamaparvovirus 4 (PsChPV-4) and a beak and feather disease virus (BFDV) detected in fecal materials of rose-ringed parakeet. The genomes of PsChPV-4 and BFDV were 4,304 and 2,009 bp long, respectively, and both genomes possessed a genomic structure consistent with their respective genera.

20.
J Comp Physiol B ; 2024 Jul 12.
Article de Anglais | MEDLINE | ID: mdl-38995419

RÉSUMÉ

With climate change increasing not just mean temperatures but the frequency of cold snaps and heat waves, animals occupying thermally variable areas may be faced with thermal conditions for which they are not prepared. Studies of physiological adaptations of temperate resident birds to such thermal variability are largely lacking in the literature. To address this gap, we acclimated winter-phenotype house sparrows (Passer domesticus) to stable warm, stable cold, and fluctuating cold temperatures. We then measured several metrics of the oxidative stress (OS) system, including enzymatic and non-enzymatic antioxidants and lipid oxidative damage, in brain (post-mitotic), kidney (mitotic), liver (mitotic) and pectoralis muscle (post-mitotic). We predicted that high metabolic flexibility could be linked to increases in reactive oxygen damage. Alternatively, if variation in ROS production is not associated with metabolic flexibility, then we predict no antioxidant compensation with thermal variation. Our data suggest that ROS production is not associated with metabolic flexibility, as we found no differences across thermal treatment groups. However, we did find differences across tissues. Brain catalase activity demonstrated the lowest values compared with kidney, liver and muscle. In contrast, brain glutathione peroxidase (GPx) activities were higher than those in kidney and liver. Muscle GPx activities were intermediate to brain and kidney/liver. Lipid peroxidation damage was lowest in the kidney and highest in muscle tissue.

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