Search Results (262)

Marek’s disease (MD), caused by pathogenic Marek’s disease virus serotype 1 (MDV-1), is one of the most important avian immunosuppressive and neoplastic diseases and has led to huge economic losses to the poultry industry worldwide. Rapid and accurate clinical diagnosis is of great significance for efficient control of the disease. Herein, we have established a multiplex PCR (mPCR) method to simply differentiate all of the three types of MDV, using five specific primers targeting to MDV-1 oncogene meq or MDV-2 and MDV-3/HVT gB genes. Simultaneously, it can detect any type of virulent or vaccine MDV strains in one PCR reaction, with amplicons of the short (S) and long (L)-meq of MDV-1 strains, and the gB of MDV-2 and HVT vaccine strains. Non-specific amplifications of avian leukosis virus (ALV), reticuloendotheliosis virus (REV), or fowl adenovirus virus 4 (FAdV-4) were not observed, indicating a good specificity of this method. A total of 522 clinical samples of tumor-bearing or suspected diseased birds collected from 30 poultry farms were detected. The results demonstrated that the newly developed mPCR method accurately detected and differentiated epidemic MDV-1 infections and vaccine strains, and provided nearly 100% consistency for detecting clinical wild-type infections compared with conventional PCR amplification of the meq gene. Collectively, our data has provided a highly efficient method for early differential diagnosis of MD clinical cases, virus identification and future evaluation of vaccination efficacy in healthy chicken flocks, which would be meaningful for efficient control of the disease. Full article

Highly pathogenic avian influenza (HPAI) H5N1 clade 2.3.4.4b continues to circulate globally across wild birds, poultry, and an expanding range of mammalian hosts, highlighting the need for antiviral strategies that address the animal–environment–human interface. The influenza A polymerase acidic (PA) endonuclease, a key enzyme in viral transcription, represents a conserved antiviral target across host species. In this study, we present a computational prioritization framework integrating homology modeling, molecular docking, molecular dynamics simulations, and physicochemical filtering to identify candidate PA endonuclease inhibitors relevant to a One Health context. Homology models of contemporary H5N1 clade 2.3.4.4b PA sequences were constructed based on the crystallographic template 6FS8 and used for cross-host docking against a targeted ligand library. Docking analysis identified baloxavir, a reference inhibitor, and entecavir, a nucleoside analog, as compounds of interest, with entecavir demonstrating favorable binding behavior, particularly in the poultry-associated model. Molecular dynamics simulations of the poultry PA–entecavir complex indicated stable interaction over 170 ns, supported by low structural deviation and favorable binding free energy (ΔG ≈ −85 kJ/mol). Physicochemical profiling suggested that entecavir possesses properties such as high polarity and predicted aqueous solubility, which were considered within the translational filtering step of this computational workflow. However, these properties do not establish antiviral efficacy or practical suitability for field use. The study provides a structured framework for integrating cross-host structural analysis with basic translational considerations, supporting the identification of candidate compounds for further biochemical and virological evaluation within the context of H5N1 control. Full article

(1) Background: The acceleration of urbanization poses an increasingly serious threat to avian diversity. Consequently, accurate species identification of avian remains is essential for biodiversity monitoring, bird rescue operations, and conservation management. (2) Methods: This study employed DNA barcoding technology based on the cytochrome c oxidase subunit I (COI) gene to analyze 112 avian remains samples collected from urban and peri-urban areas of Tianjin city. (3) Results: A total of 47 bird species were identified, belonging to 11 orders, 24 families, and 30 genera, achieving an overall identification success rate of 95.54%. Passeriformes were dominant, accounting for 70.21% of the identified species. The species list includes 3 species listed as Class I nationally protected birds and 7 species as Class II nationally protected birds. Discrepancies between preliminary morphological identification and molecular identification results highlighted the complementary roles of the two approaches. (4) Conclusions: This study demonstrates that DNA barcoding is an effective tool for efficiently identifying degraded avian remains in urban environments. It provides reliable data for biodiversity assessments, wildlife rescue, and conservation management, while also supporting improved identification accuracy through the integration of molecular and morphological methods. Full article

Avian influenza, a disease caused by avian influenza virus (AIV), mainly infects birds but can also infect mammals, which poses a serious threat to public health. Therefore, thorough understanding of its pathogenic mechanism and the identification of antiviral targets are essential for the prevention, control, and treatment of AIV. The polymerase acidic protein (PA) is a core component of the viral RNA-dependent RNA polymerase complex and plays a central role in viral transcription through its cap-snatching activity during early infection. We employed a multi-omics approach combining transcriptome analysis with PA interaction proteomics to characterize host responses during AIV infection and explore the PA–host interaction network. Transcriptomics revealed a polarized host response marked by activated translation-related processes, mitochondrial energy metabolism, and innate immune signaling, alongside broad suppression of nuclear transcriptional regulation and cell cycle pathways. Immunoprecipitation–mass spectrometry identified host proteins associated with PA that were enriched in RNA metabolism, ribosome biogenesis, and protein homeostasis. Integrative analysis of transcriptomic and interactome data, along with protein–protein interaction network analysis, prioritized a subset of high-confidence PA-interacting host factors. Among these, ribosomal protein RPS27A was validated to interact with PA and to support viral replication during early infection in this study. Full article

The Cretaceous dinosaur record from Normandy, in NW France, is reviewed. It includes several enigmatic specimens that were briefly mentioned in short notes published during the 19th and 20th centuries that have since then been destroyed in World War II or lost. Since they were neither described in detail nor illustrated, their identification must remain uncertain, but some may have been ankylosaur remains, while another specimen may have belonged to a bird or a non-avian theropod. Specimens that were properly described and are kept in museums in Normandy come from Albian and Cenomanian horizons in the coastal cliffs of Seine-Maritime. The Albian record, from Cape La Hève (Le Havre) includes an incomplete titanosaurian sauropod skeleton, described as Normanniasaurus genceyi, and an isolated caudal vertebra from the same provenance, probably belonging to that taxon. The Cenomanian record is limited to a group of bones and a tooth of the furileusaurian abelisaurid theropod Caletodraco cottardi from the glauconitic Chalk at Saint-Jouin-Bruneval. All these specimens come from marine sediments and are in all likelihood derived from floating carcasses that drifted over a fairly long distance from an emergent land area corresponding to the Armorican massif in the west. Although scanty, the record from Normandy sheds some light on the poorly known dinosaurs that inhabited north-western Europe during the middle part of the Cretaceous, some of which apparently had Gondwanan affinities. Full article

Accurate body-weight monitoring is essential for assessing welfare in cage-free poultry. However, commercial farms continue to rely on manual weighing because of concerns regarding the accuracy and reliability of automated methods. This study developed and evaluated an Internet of things (IoT)-enabled weighing platform integrating load cells, an microcontroller, a Raspberry Pi 5, and Node-RED for data acquisition, processing, and visualization. The system recorded weight measurements at 1 Hz, detected individual weighing sessions, and applied a rolling-median filter to produce stable weight estimates. Validation was performed against a reference scale during two weighing sessions one week apart using 75 cage-free hens randomly selected from a flock of 750 Hy-Line W80 birds. Bland–Altman analysis and a linear mixed-effects model indicated a small overestimation of approximately 6–9 g, with most measurements falling within the 95% limits of agreement, while overall mean absolute percentage error remained below 3%. Improved accuracy during the second session suggests that platform stability influenced performance. Overall, the system demonstrates strong potential for continuous low-stress weight monitoring in poultry farms. Future improvements should focus on refining calibration methods, enhancing mechanical stability, and integrating bird identification and presence-detection mechanisms to further support flock management and welfare monitoring. Full article

Pasteurella multocida is a pathogen of numerous mammal and bird species. Based on capsular antigens, five capsular types of P. multocida (A, B, D, E, and F) are distinguished. The aim of this study was to evaluate the usefulness of multiplex PCR and MALDI-TOF MS for the identification and capsular typing of P. multocida strains isolated from rabbits. A total of 115 field strains previously classified as P. multocida, isolated in Poland between 1999 and 2020, were analysed. Multiplex PCR was applied for simultaneous species identification and determination of capsular types. Most strains belonged to capsular type A (87.8%), while capsular types D (8.7%) and F (3.5%) were detected less frequently. The examined strains were subsequently identified by MALDI-TOF MS, which correctly assigned all strains to the species P. multocida. The results demonstrate that multiplex PCR is a rapid and reliable alternative to conventional species identification and serological capsular typing of P. multocida. In addition, MALDI-TOF MS proved to be a valuable tool for accurate species-level identification. The application of these methods in routine clinical microbiology laboratories may significantly improve the speed and reliability of P. multocida identification. Full article

The possibility of sex identification in birds is of substantial importance for studies on various aspects of their ecology and behaviour. Discriminant functions have become increasingly popular in studies of bird species that are monomorphic in plumage characteristics because these methods are inexpensive and non-invasive. In this paper, we provide the first discriminant function that could potentially aid in determining sex in a common wader species, the Wood Sandpiper, based on external body measurements. Females were larger than males in all linear body measurements; however, no single measurement can be used to determine sex due to the high degree of overlap between the sexes. Discriminant equation with the most commonly used linear measurements, wing length and bill length, was provided. Identifying birds with discriminant function values D₃ < –0.409 as males and those with D₃ > 0.217 as females would lead to sex misclassification of only 5% of individuals of each sex, but it would leave as many as 83% of the individuals unsexed. Allowing for a misclassification of 10% would shift the cut-off values to −0.509 for males and 0.633 for females and reduce the number of unsexed birds to 66%. The method presented here allows us to account for sex-specific patterns in future ecological studies of the Wood Sandpiper and can be applied to past data. Full article

Sexual size dimorphism (SSD) refers to the phenomenon where males and females of the same species exhibit differences in overall or partial body size, and it is widespread among mammals, birds, reptiles, and fish. Notably, this dimorphism is significantly influenced by the sexually dimorphic secretion of growth hormone (gh), a key pituitary-derived growth regulator. Commonly, the secretion of gh is positively regulated by glucagon family members such as growth hormone-releasing hormone (ghrh) and adenylate cyclase-activating polypeptide 1 (adcyap1). To explore the stimulators for pituitary hormones (especially gh) in the teleost, we performed genome-wide identification and functional characterization of the glucagon family on Chinese tongue sole (Cynoglossus semilaevis) that exhibits typical female-biased sexual size dimorphism. Four members of adcyap1/vasoactive intestinal polypeptide(vip)/ghrh family and ten members of their receptor family were identified. Expression pattern analysis revealed high expression of adenylate cyclase-activating polypeptide 1b (adcyap1b) and its receptors in the brain. Moreover, two alternative splice variants for the adcyap1b gene were discovered, resulting from the skipping of exon 4. Following the acquisition of the two eukaryotic recombinant protein splice variants (ADCYAP1b_tv1 and ADCYAP_tv2) from HEK 293T cells, incubation experiments were conducted using C. semilaevis pituitary cell line. The results demonstrated that both variants promoted the expression of gh, pro-opiomelanocortin (pomc), and corticoliberin (crh), but ADCYAP1b_tv1 had a significantly stronger effect and uniquely stimulated prolactin (prl) and somatolactin (sl). This study demonstrates a functional divergence between the two ADCYAP1b splice variants in teleosts, with ADCYAP1b_tv1 acting as a more potent and versatile pituitary hormone stimulator. Further research on their receptor-binding affinity and downstream signaling pathways would be valuable for exploring the mechanism underlying sexual size dimorphism. Full article

Passive acoustic monitoring (PAM) is an automatic and non-invasive method for long-term monitoring of bird vocal activity. PAM generates a large amount of data, and the automatic recognition of data poses significant challenges. BirdNET is a free-to-use sound algorithm. We evaluated the effectiveness of BirdNET in identifying the vocalizations of Chinese Bamboo Partridge (a Chinese endemic species) and proposed a random forest (RF) method to improve the result based on the detection of BirdNET. The diurnal and seasonal patterns of calling activity were described based on the identification results. The results showed that the recall of BirdNET-Analyzer was 16.6%, the precision of BirdNET-Analyzer-XHS was 50.8%, and the recall and precision of the RF model were 75.2% and 74.4%, respectively. The diurnal vocal activity of the Chinese Bamboo Partridge showed a bimodal pattern, with peaks around sunrise and sunset and low vocal activity during the central hours of the day. The seasonal vocal activity displayed a unimodal pattern, with a peak in vocal activity during April and May. This study used the Chinese Bamboo Partridge as an example and proposes an improved RF model, built on BirdNET recognition results, for species identification, providing a practical approach for recognizing the vocalizations of regional species. Full article

In recent times, field crop damage caused by birds, such as corvids and pigeons, has become crucial for many farmers. Damage can be as serious as the loss of a large part of the harvest. Several solutions have been proposed, but none are effective. An example is the use of scarecrows, but birds eventually adapt to them over time, and so they become ineffective. To study bird behavior and to propose a bird deterrent that would adapt to the presence of birds, we set up an experimental image-taking system on several plots of land over a period of 4–5 years. Around fifteen terabytes of images taken in the field were acquired. Our aim was to automatically detect these birds using deep learning methods and then to activate a real-time scarer. This work meets two challenges: the first is agroecological, as bird damage has become a major issue, and the second is IT, as it is difficult to detect birds in the field: the individuals are small because they are far from the camera lens, and field conditions are often less than optimal: darkness, confusion between the pigeons’ colors and the ground, etc. The Mask-RCNN in its original configuration is not suited to detecting small individuals. We mainly focused on the model’s hyperparameters to better adapt it to our study context. As a result, we improved the detection of small individuals using, among other things, appropriate anchor scales design and image processing techniques. At the same time, we built an original dataset focused on small individuals called BirdyDataset. The model can detect corvids and pigeons with an accuracy of 78% under real field conditions. Full article

Climate change poses an unprecedented threat to global biodiversity, with birds serving as critical indicators of ecosystem responses. This study assessed the impacts of climate change on 29 endangered bird species in South Korea, a critical stopover region within the East Asian-Australasian Flyway (EAAF). Using Random Forest models, we predicted current (2010 baseline) and future species distributions under two climate scenarios (SSP2-4.5 and SSP5-8.5) for four time periods (2030s, 2050s, 2070s, and 2090s). Model performance was robust, with a mean AUC of 0.844 ± 0.122 across all species and 72.4% of species achieving AUC ≥ 0.80. Elevation emerged as the most influential predictor for 44.8% of species, followed by precipitation of the driest month (17.2%) and distance to water bodies (10.3%). Current species richness patterns showed spatial heterogeneity, with higher concentrations along coastal wetlands, particularly in the western and southern coasts and Jeju Island. Under SSP2-4.5, species richness patterns remained relatively stable through 2090, while SSP5-8.5 projected more dramatic shifts, particularly after 2070. Coastal regions and national parks exhibited differential responses, with some areas showing increases and others experiencing declines in species richness. High-elevation national parks, including Mt. Hallasan, Mt. Seoraksan, and Mt. Odaesan, demonstrated potential to serve as climate refugia, maintaining relatively stable species richness under both scenarios. Our spatial analysis at municipality and national park levels identified priority conservation areas and emphasized the need for climate refugium identification, habitat connectivity along elevational gradients, and adaptive management strategies. The findings provide actionable guidance for science-based conservation planning and contribute to international efforts to protect migratory birds along the EAAF. Urgent conservation measures are needed to safeguard coastal wetlands and establish ecological corridors to facilitate species range shifts under changing climatic conditions. Full article

To address the challenge of bird species detection on transmission lines, this paper proposes a detection method based on dual data enhancement and an improved YOLOv8s model. The method aims to improve the accuracy of identifying small- and medium-sized targets in bird detection scenes on transmission lines, while also accounting for the impact of changing weather conditions. To address these issues, a dual data enhancement strategy is introduced. The model’s generalization ability in outdoor environments is enhanced by simulating various weather conditions, including sunny, cloudy, and foggy days, as well as halo effects. Additionally, an improved Mosaic augmentation technique is proposed, which incorporates target density calculation and adaptive scale stitching. Within the improved YOLOv8s architecture, the CBAM attention mechanism is embedded in the Backbone network, and BiFPN replaces the original Neck module to facilitate bidirectional feature extraction and fusion. Experimental results demonstrate that the proposed method achieves high detection accuracy for all bird species, with an average precision rate of 94.2%, a recall rate of 89.7%, and an mAP@50 of 94.2%. The model also maintains high inference speed, demonstrating potential for real-time detection requirements. Ablation and comparative experiments validate the effectiveness of the proposed model, confirming its suitability for edge deployment and its potential as an effective solution for bird species detection and identification on transmission lines. Full article

The cage-free rearing of laying hens combined with probiotics promotes intestinal health. The aim of this study was to evaluate the effect of adding probiotics on the intestinal microbiota of Isa Brown laying hens raised in a cage-free system. A total of 450 Isa Brown hens, 19 weeks old, were used in a cage-free system over three 28-day cycles in a completely randomized design with five treatments and six replicates, containing 15 birds per pen. The Isa Brown hens were fed a basal ration based on corn and soybean meal; a basal ration plus a single strain of Bacillus subtilis (500 g/t); a basal ration plus a single strain, Bacillus subtilis (1000 g/t); a basal ration plus a probiotic blend (Bacillus subtilis, Enterococcus faecium, Lactobacillus acidophilus, Lactobacillus delbrueckii, Lactobacillus plantarum, Lactobacillus reuteri, Lactobacillus salivarius, Pediococcus acidilactici) at a dosage of 200 g/t; and a basal ration plus the blend at 400 g/t. From one hen per replicate, contents from the small intestine, including the duodenum, jejunum, and ileum, were collected for DNA extraction and bacterial species identification. There was an increase in Helicobacter brantae, which was quantified at 86% in the diet containing 1000 g/t of the probiotic single strain of Bacillus subtilis and 87% in the diet containing 500 g/t dosage, in comparison to the basal ration. With the probiotic blend at 200 g/t, 37% Lactobacillus crispatus and 21% Lactobacillus aviarius were observed, while the dosage of 400 g/t of the probiotic blend increased the level of Lactobacillus kitasatonis to 68% compared to the basal ration. The inclusion of 200 g/t of the probiotic blend proved to be more beneficial to the small intestinal microbiota of laying hens. Full article

Urban green spaces are essential components of city ecosystems, providing environmental and social benefits while simultaneously serving as potential entry points for invasive plant pathogens. In recent years, increasing attention has been directed toward the role of urban environments as reservoirs and transmission corridors for oomycetes, a group of highly destructive microorganisms affecting trees and shrubs. This study aimed to investigate the diversity and potential introduction pathways of oomycetes in three Warsaw parks representing distinct ecological settings: a historical city park, a large landscape park with aquatic features, and a newly constructed linear park. Samples of soil, and surface water were collected and analysed using standard isolation and molecular identification methods. Four species were identified: Phytophthora cactorum, P. cambivora, Phytopythium vexans, and Ph. montanum—the latter two representing first records for urban parks in Poland. The results indicate that nursery plant material, surface water systems, and wildlife activity, particularly birds, are likely contributors to the introduction and spread of these pathogens in city landscapes. The findings underscore the growing phytosanitary risk associated with urban greenery, where the interplay of anthropogenic disturbance, high plant turnover, and complex hydrological networks facilitates pathogen establishment. This research highlights the urgent need to integrate urban biosecurity strategies with routine molecular monitoring, nursery inspections, and wildlife surveillance to limit further dissemination of invasive oomycetes and enhance the resilience of urban tree populations. Full article