Search Results (228)

MOTS-c is a mitochondrial peptide that plays a crucial role in regulating energy metabolism, gene expression, and immune processes. However, current research primarily focuses on mammals like humans and mice, with no reports on avian MOTS-c. This study aimed to identify and characterize MOTS-c coding sequences across major poultry species through bioinformatics analysis and experimental validation. The alignment results showed high sequence similarity in the MOTS-c coding regions between avian and mammalian species. However, a single nucleotide deletion was identified in avian sequences at the position corresponding to the fourth amino acid residue of mammalian homologs, resulting in divergent downstream amino acid sequences. Despite this deletion, several residues were conserved across species. Phylogenetic analysis of mRNA sequences grouped pigeons with mammals, while protein sequence analysis revealed that poultry and mammals form separate branches, highlighting the divergence between avian and mammalian MOTS-c sequences. Tissue expression profiling demonstrated widespread distribution of chicken MOTS-c across multiple tissues, with the highest expression levels in the heart. Fasting significantly reduced heart MOTS-c expression, suggesting potential metabolic regulatory functions. Functional analysis of MOTS-c in primary hepatocytes revealed significant enrichment of the ribosome, oxidative phosphorylation, and key signaling pathways (PI3K-AKT and JAK-STAT) following 24 hours of treatment. Western blot validation confirmed MOTS-c-mediated activation of the AKT signaling pathway. This study represents the first comprehensive characterization of avian MOTS-c, providing critical insights into its evolutionary conservation and its potential functional roles in gene expression and cellular metabolism. Our findings establish a foundation for further investigation into the functions of mitochondrial-encoded peptides in avian species. Full article

Enteric diseases represent one of the main causes of morbidity and mortality in poultry production, especially in turkeys (Meleagris gallopavo), significantly affecting the profitability of the sector. Turkey enteric complex (PEC) is a multifactorial syndrome characterized by diarrhea, stunting, poor feed conversion, and increased mortality in young turkeys. Its aetiologia includes multiple avian enteric viruses, including astrovirus, rotavirus, reovirus, parvovirus, adenovirus, and coronavirus, which can act singly or in co-infection, increasing clinical severity. This study performs a systematic review of the literature on these viruses and a meta-analysis of their prevalence in different regions of the world. Phylogenetic analyses were used to assess the genetic diversity of the main viruses and their geographical distribution. The results show a wide regional and genetic variability, which underlines the need for continuous epidemiological surveillance. Health and production implications are discussed, proposing control strategies based on biosecurity, targeted vaccination, and optimized nutrition. These findings highlight the importance of integrated management to mitigate the impact of CSF in poultry. Full article

Respiratory viral diseases infecting poultry lead to variable lesions in the respiratory organs, including nasal sinuses, trachea, lungs, and air sacs. Additional involvement of eyelids/conjunctiva was reported. The distribution and the intensity of lesions depend on multiple factors, including virulence, the host’s immunity, and secondary or concurrent infections. It may be challenging to detect remarkable lesions during experimental infections conducted in a controlled environment because some viruses fail to produce the intense lesions seen in field cases. This creates a challenge in developing a reliable model to study pathogenicity or vaccine efficacy experimentally. The development of the proposed histologic respiratory index (HRI) aims to help monitor the least microscopic changes that can be scored, thereby creating an objective and accurate grading of lesions in experimentally infected birds. HRI scores the changes in eyelids/conjunctiva and respiratory mucosa, including hyperplasia, metaplasia, inflammatory cellular infiltration in the submucosa, including lymphocytes and heterophils, and vascular changes (vasculitis) in nasal sinuses, trachea, and lungs. The score was validated in birds infected experimentally with avian metapneumovirus (aMPV) and low pathogenic avian influenza (LPAI-H4N6). The HRI reliably graded higher scores in the respiratory organs of experimentally infected birds compared with non-infected control ones. The HRI is the first of its type with poultry viral respiratory pathogens and it was initially proven to be a reliable in pathogenicity and vaccine trials of certain poultry respiratory viral diseases. Full article

The Brazilian Araucaria Forest (AF) now covers only 1% of its original extent due to significant degradation, making conservation a challenge. The AF occurs in a mosaic alongside grassland and Atlantic Forest ecosystems, influencing bird species’ distribution through ecological processes. We compared the composition and functional diversity of the bird community along a gradient of AF cover in a protected area (Pró-Mata Private Natural Heritage Reserve) in southern Brazil. Bird sampling was conducted using MacKinnon lists along five trails with different histories of vegetation suppression, based on forest cover estimates from landscape imagery. Birds were functionally classified based on morphological and ecological traits. We recorded 191 bird species in total. We found higher bird richness in trails with less forest cover, while functional diversity responded inversely to vegetation cover. Bird species composition shifted from more open-habitat specialists to more forest specialists with the increasing forest cover and vegetation structural complexity. These findings highlight the ecological importance of maintaining vegetation heterogeneity, as vegetation mosaics enhance avian species richness and support a broader range of functional traits and ecosystem processes. We recommend the conservation of Araucaria Forest–grassland mosaics as a strategic approach to support multidimensional biodiversity and sustain key ecological functions in southern Brazil. Full article

Orthoflaviviruses (formerly flaviviruses) are known for their role in numerous diseases affecting both humans and animals. Despite the worldwide distribution of orthoflaviviruses, individual species are only found in endemic or epidemic regions. However, in recent decades, certain orthoflaviviruses have spread beyond their traditional geographic boundaries, even crossing continents. Given the long-distance movements of birds, the knowledge of zoonotic orthoflaviviruses associated with birds is essential because of their possible introduction into new regions, as was the case with West Nile virus and Usutu virus. A thorough literature review was conducted on zoonotic orthoflaviviruses related to birds, including lesser-known (re-)emerging and neglected orthoflaviviruses that are limited to specific regions and/or avian hosts but have the potential to spread to a wider geographical area and pose a higher risk of transmission to humans. Several of these viruses possess significant zoonotic potential and can cause a wide spectrum of diseases in humans, ranging from mild febrile illnesses (Zika virus) to severe neuroinvasive diseases (tick-borne encephalitis, West Nile, Japanese encephalitis virus) and hemorrhagic fevers (yellow fever, dengue virus). Geographic distribution, hosts, vectors, incidence of human infections, and impact on human and animal health of zoonotic flaviviruses related to birds are critically reviewed. The viruses have been categorized based on the role of birds as an orthoflavivirus host and the clinical presentation in human infections. Full article

The avian intestinal microbiota is a vital interface for host/environment interactions, playing a pivotal role in nutrient metabolism, immune regulation, and ecological adaptation. In the Yellow River Delta region, common cranes and white cranes coexist in mixed flocks. During the winter, when food resources are scarce, studying their gut microbiota can effectively reveal the feeding patterns of these two crane species, thereby providing valuable data for crane conservation efforts. This study systematically investigated and compared the intestinal microbiota structures of white cranes (Grus leucogeranus) and common cranes (Grus grus) inhabiting the Yellow River Delta region. The results demonstrated that the predominant phyla of the intestinal microbiota in white and common cranes are Firmicutes and Proteobacteria at the phylum level; Catellicoccus and Lactobacillus were the predominant genera in the crane species. LEfse was used to analyze the differential flora of the intestinal bacterial communities of white cranes and common cranes and to detect the marker species with significant differences between the groups. Based on the COG database, a preliminary functional prediction of the intestinal microbiota was conducted, and 16 metabolic pathways relating to the COG pathway were obtained. In general, although both types of cranes belong to the Grus genus and are distributed in the same area, there are significant differences in the composition and functional characteristics of their intestinal microbiota due to the differences in their feeding composition. Full article

Vehicle collisions with wild animals are a significant cause of wild animal mortality. This impacts their population and spatiotemporal distribution within the ecosystem. Data on the impact of road kills on wild animals, particularly in the south-central part of Uganda, are not present. This study aimed to investigate the number of species involved in road kills in South-Central Uganda and their spatial and temporal distribution within South-Central Uganda. Three transects, each 40 km in length, were surveyed. In both wet and dry seasons, surveys were conducted monthly in the morning and afternoon from November 2019 through April 2024. The findings showed that 161 wildlife–vehicle accidents were detected within a four-and-a-half-year period, with 178 animal species involved. These incidents belonged to 12 mammals, five reptiles, two amphibians, and 32 avian families. Our study adds to a better understanding of the impact of roads on wildlife in Africa and is an essential starting point regarding conservation efforts to mitigate these effects. It provides a first summary of species that are frequently found as roadkill in this area of south-central Uganda. This acts as a reference point for future studies. Full article

Tennessee’s ecological diversity, spanning forests, farmland, and urban areas, provides an ideal foundation for applying the One Health approach, which integrates human, animal, and environmental health. This review examines Tennessee’s current One Health landscape, highlighting active initiatives, ongoing challenges, and future directions. Key efforts involve workforce development, disease surveillance, outbreak response, environmental conservation, and public education, led by a coalition of state agencies, universities, and the Tennessee One Health Committee. These programs promote cross-sector collaboration to address issues such as zoonotic diseases, climate change, land use shifts, and environmental contaminants. Notably, climate-driven changes, including rising temperatures and altered species distributions, pose increasing threats to health and ecological stability. Tennessee has responded with targeted monitoring programs and climate partnerships. Education is also a priority, with the growing integration of One Health into K–12 and higher education to build a transdisciplinary workforce. However, the state faces barriers, including limited funding for the One Health workforce, undefined workforce roles, and informal inter-agency data sharing. Despite these obstacles, Tennessee’s successful responses to outbreaks like avian influenza and rabies demonstrate the power of coordinated action. To strengthen its One Health strategy, the state must expand funding, formalize roles, improve data systems, and enhance biodiversity and climate resilience efforts positioning itself as a national leader in interdisciplinary collaborative solutions. Full article

Background: The order Suliformes exhibits significant karyotype diversity, with Sula species showing a Z₁Z₁Z₂Z₂/Z₁Z₂W multiple-sex chromosome system, an uncommon occurrence in avians. Satellite DNAs (satDNAs), which consist of tandemly repeated sequences, often vary considerably even among closely related species, making them valuable markers for studying karyotypic evolution, particularly that of sex chromosome evolution. This study aims to characterize and investigate the potential role of these sequences in the karyotypic evolution of the group, with special attention to the sex chromosomes. Methods: Through characterizing satDNAs in two Suliformes species (Sula leucogaster and Nannopterum brasilianum) using BGISEQ-500 platform and bioinformatics analysis. Their chromosomal distribution was mapped by fluorescence in situ hybridization (FISH) within their own karyotypes and in three additional Suliformes species (S. sula, S. dactylatra, and Fregata magnificens). Results: Five satDNAs were identified in S. leucogaster and eight in N. brasilianum. Within the genus Sula, three species shared specific satDNA sequences, although with different hybridization patterns. In contrast, the satDNAs of N. brasilianum were species-specific. Additionally, the Z chromosome, including Z₂ in Sula species, showed reduced accumulation of repetitive DNAs. Conclusions: These results suggest that differential accumulation of repetitive sequences may have contributed to the diversification of karyotypes in this group, particularly influencing the structure and differentiation of sex chromosomes. Full article

A characteristic feature of influenza A viruses is their high capacity for reassortment, significantly increasing their genetic diversity. This can lead to the formation of influenza A virus variants with unique phenotypic characteristics, particularly those with pandemic potential. Representatives of the H4N9 subtype are low-pathogenic influenza A (LPAI) viruses. Despite their low pandemic potential, these viruses may represent an important reservoir of genes for genetic exchange with other IAVs. Here, we analyzed the reassortment events of H4N9 viruses using all publicly available sequences. Several computational approaches, including phylogenetic reconstructions and reassortment detection algorithms (PDDM and PDCP), were used to identify phylogenetic incongruences. Numerous reassortment events were detected in H4N9 viruses, especially in the NS segment. This suggests extensive genetic exchange with other avian and mammalian IAVs. In addition, a comparison of phylogenetic and geographic patterns suggests that H4N9 viruses have undergone multiple trans-regional transmissions. These results suggest that LPAI viruses make a significant contribution to the overall influenza gene pool, increasing the likelihood of the emergence of new IAV variants with unpredictable phenotypic characteristics. However, our results suggest that the current understanding of the real distribution and genetic diversity is fragmented. Therefore, better monitoring and surveillance of H4N9 viruses should improve influenza pandemic preparedness. Full article

Ecoacoustics examines the interactions between soundscapes, ecological processes, and anthropogenic disturbance. Acoustic communication is crucial for wildlife, making noise pollution a key factor in shaping biodiversity, though its effects are also modulated by habitat characteristics. In this work, we assess the influence of highway noise and vegetation structure on the soundscape and avian distribution of the Moriano oxbow lake (Bereguardo, PV, Italy), a Site of Community Importance in the Ticino Valley Regional Park. A two-week monitoring campaign (April 2022) used eight recorders arranged in a grid to analyze soundscape dynamics through eight ecoacoustic indices (ACI, ADI, AEI, BI, NDSI, H, DSC, ZCR). Vegetation surveys quantified tree diversity and structural parameters such as basal area, height, stem density, biomass, and leaf cover. Correlation analyses revealed that Quercus robur abundance and tree diversity significantly influenced the acoustic environment, while bird richness correlated positively with vegetation biomass and Quercus robur presence. Highway proximity was a key structuring factor, with indices (ADI, H, NDSI, ACI) increasing with distance. These findings underscore the dual role of noise and vegetation in shaping soundscapes and highlight the importance of incorporating habitat features into ecoacoustic assessments to better understand biodiversity patterns in anthropized landscapes. Full article

The Eurasian eagle-owl (Bubo bubo) is a large, generalist predator widely distributed across Eurasia, including mainland Greece, where it occupies a broad range of habitats. Its diet is known to consist primarily of mammals and birds, with reptiles occasionally included. However, to date, chameleons have not been documented among its prey. Here, we report the first confirmed case of B. bubo preying on an African chameleon (Chamaeleo africanus) in the western Peloponnese of southern Greece—a region where the two species occur in limited sympatry. C. africanus, native to North Africa and introduced to Greece since antiquity, is a diurnal, slow-moving, arboreal lizard with highly cryptic behavior and specialized anti-predator strategies. Despite these traits, our observation highlights its potential vulnerability to nocturnal avian predators. This rare predation event offers novel insights into the trophic ecology of B. bubo and raises important considerations for the conservation of C. africanus, a species listed as Critically Endangered in Greece and increasingly threatened by habitat loss, illegal collection, and road traffic collisions. Full article

Dermanyssus gallinae, Ornithonyssus sylviarum, and Ornithonyssus bursa are ectoparasitic bird mites that affect both avian hosts and humans, causing economic losses in poultry farming and dermatological issues in humans. Due to their small size and transient feeding behaviour, mite-induced dermatitis is often misdiagnosed. In this study, over 4900 cases of entomodermatoses, recorded at the Urania Research Centre and the Department of Veterinary Medicine of Perugia—Parasitology Section between 2010–2024, were analysed, selecting cases linked to bird mites. Data on lesion onset, timing, infestation location, environmental factors, lesion type, and symptoms were examined. Avian Dermanyssoidea mites were responsible for about 4% of dermatological cases, with D. gallinae and O. sylviarum being the most prevalent, while O. bursa was less frequent. Species identification was also based on the morphology of the chelicerae and palps, with cases peaking in spring and summer. These mites were widely distributed across Italy, and Ornithonyssus species caused more severe skin reactions than Dermanyssus. Infestations often involved both genera. This study provides the first large-scale analysis of bird mite infestations in Italy, offering new insights into their distribution, infestation dynamics, and clinical symptoms. The findings contribute to improving diagnostic accuracy, pest control strategies, and public health interventions. Full article

Haemosporidian parasites (Apicomplexa, Haemosporida) are diverse obligatory heteroxenous protists, which infect all major groups of terrestrial vertebrates and use dipterous blood-sucking insects as vectors. These pathogens are responsible for various diseases, including malaria, which remains an important human and animal illness. In the wild, haemosporidians are particularly diverse in reptiles and birds in tropical countries, where they are flourishing. Avian haemosporidians have been particularly extensively investigated, especially due to their high prevalence and global distribution, including the countries with cold climates. The general scheme of the life cycle of haemosporidians is known, but the details of development remain insufficiently investigated or even unknown in most of the described parasite species, suggesting the existence of knowledge gaps. This attracts attention to some recent observations, which remain fragmentary but suggest the existence of formerly neglected or underestimated modes of the haemosporidians’ survival in vertebrates. Such findings are worth discussion as they indicate the novel directions in wildlife haemosporidian research. This article overviews some recent findings, which call for broadening of the orthodox views on modes of existence of haemosporidian parasites in avian hosts. Among them are the role of blood merogony in the long-lasting persistence of malaria parasites in birds, the role of gametocytes in the long-lasting survival of Haemoproteus species in vertebrates, the possible reasons of undetectable avian Haemoproteus infections due to peculiarities of exo-erythrocytic development, and the plausible factors driving the narrow vertebrate host specificity of Haemoproteus species. Full article

With the first evidence of the association between bats and influenza A viruses, various studies have begun to emerge to understand this interesting and important association among bats conservation, animal health, and public health. This study aimed to verify the presence of anti-influenza A vipothesrus antibodies, as well as the molecular identification of these viruses in bats distributed in forest fragments located in southeastern Mexico. Blood samples were obtained from 600 bats belonging to 24 different species, using an enzyme immunoassay to detect antibodies against the nucleoprotein antigen of the avian influenza A virus. Likewise, oropharyngeal swabs, rectal swabs and organs were taken for quantitative reverse transcription PCR (qRT-PCR) of these viruses. A total of six bats (1%) tested positive either by serology or molecular methods, not both simultaneously. Although this suggests a very low prevalence of influenza A viruses in Mexican bats, it is the first study to address this association and, following the precautionary principle, we consider it necessary to establish systematic monitoring of the presence of influenza A in bats, since they are known to harbor infectious agents with zoonotic potential. Furthermore, it is possible that the association of influenza A viruses circulating in Latin American bats has an important co-evolutionary component with some bat species with exclusive distribution in the American continent. Full article