Search Results (129)

Leptospirosis is a globally significant zoonosis affecting animal health, productivity, and the environment. While typically associated with tropical climates, its persistence in semi-arid regions such as La Laguna, Mexico—characterized by low humidity, high temperatures, and limited water sources—remains poorly understood. Although these adverse environmental conditions theoretically limit the survival of Leptospira, high livestock density and synanthropic reservoirs (e.g., rodents) may compensate, facilitating transmission. In this cross-sectional study, blood sera from 445 dairy cows (28 herds: 12 intensive [MI], 16 semi-intensive [MSI] systems) were analyzed via microscopic agglutination testing (MAT) against 10 pathogenic serovars. Urine samples were cultured for active Leptospira detection. Risk factors were assessed through epidemiological surveys and multivariable analysis. This study revealed an overall apparent seroprevalence of 27.0% (95% CI: 22.8–31.1), with significantly higher rates in MSI (54.1%) versus MI (12.2%) herds (p < 0.001) and an estimated true seroprevalence of 56.3% (95% CI: 50.2–62.1) in MSI and 13.1% (95% CI: 8.5–18.7) in MI herds (p < 0.001). The Sejroe serogroup was isolated from urine in both systems, confirming active circulation. In MI herds, rodent presence (OR: 3.6; 95% CI: 1.6–7.9) was identified as a risk factor for Leptospira seropositivity, while first-trimester abortions (OR:10.1; 95% CI: 4.2–24.2) were significantly associated with infection. In MSI herds, risk factors associated with Leptospira seropositivity included co-occurrence with hens (OR: 2.8; 95% CI: 1.5–5.3) and natural breeding (OR: 2.0; 95% CI: 1.1–3.9), whereas mastitis/agalactiae (OR: 2.8; 95% CI: 1.5–5.2) represented a clinical outcome associated with seropositivity. Despite semi-arid conditions, Leptospira maintains transmission in La Laguna, particularly in semi-intensive systems. The coexistence of adapted (Sejroe) and incidental serogroups underscores the need for targeted interventions, such as rodent control in MI systems and poultry management in MSI systems, to mitigate both zoonotic and economic impacts. Full article

Small rodents are known hosts of various pathogens, including Hepatozoon, but until now, in Brazil, only Hepatozoon milleri has been described in these animals. In this study, liver samples and blood smears were obtained from 289 rodents belonging to 14 Cricetidae and two Muridae species that had been captured in municipalities of the states of Paraná and Rio de Janeiro. Smears were stained with Giemsa, and gametocytes were detected via microscopy in 10.72% (n = 31/289) of samples, with these individuals representing three rodent species. Significant morphometric differences were observed in gametocyte measurements in Akodon rodents. Using conventional PCR, Hepatozoon spp. 18S rDNA fragments were amplified in 24.91% (n = 72/289) of samples, with those individuals representing seven rodent species. Phylogenetic analyses clustered 41 sequences from this study into a subclade with other sequences from small mammals in Brazil, identifying four distinct haplotypes, and, for the first time, a relationship between Hepatozoon haplotype and gametocyte length was observed. Based on phylogenetic analysis, this study reinforces the trophic relationship between rodents and reptiles as a possible link in the Hepatozoon transmission cycle in South America. Furthermore, our findings expand knowledge on Hepatozoon spp. hosts, describing Oxymycterus nasutus and Oxymycterus quaestor as new host species and identifying two novel circulating haplotypes in rodents from Paraná State, southern Brazil. Full article

Canine morbillivirus (CDV), the cause of canine distemper, is a pathogen affecting many hosts. While modified live virus (MLV) vaccines are crucial for controlling the disease in dogs, cases of vaccine-related infections have been found in both domestic and wild animals. Specifically, the America-1 and Rockborn-like vaccine genotypes are concerning due to their spread and ability to transmit between different species. This study conducted a review and analysis of molecular detections of these strains in various carnivores (domestic, captive, synanthropic, and wild species). This study used a conceptual model considering host ecology and the domestic–wild interface to evaluate plausible transmission connections over time using Linear Directional Mean (LDM) and Weighted Mean Centre (WMC) methods. Statistical analyses examined the relationship between how likely a strain is to spread and factors like host type and vaccination status. The findings showed that the America-1 genotype spread in a more organised way, with domestic dogs being the main source and recipient, bridging different environments. Synanthropic mesocarnivores also played this same role, with less intensity. America-1 was most concentrated in the North Atlantic and Western Europe. In contrast, the Rockborn-like strain showed a more unpredictable and restricted spread, residual circulation from past use rather than ongoing spread. Species involved in vaccine-related infections often share characteristics like generalist behaviour, social living, and a preference for areas where domestic animals and wildlife interact. We did not find a general link between a host vaccination status and the likelihood of the strain spreading. The study emphasised the ongoing risk of vaccine-derived strains moving from domestic and synanthropic animals to vulnerable wild species, supporting the need for improved vaccination approaches. Mapping these plausible transmission routes can serve as a basis for targeted surveillance, not only of vaccine-derived strains, but of any other circulating genotype. Full article

Among synanthropic species, European hedgehogs are widely distributed throughout Europe. In recent decades, these animals have increasingly adapted to anthropogenic environments, where they find abundant shelter and food resources, along with fewer natural predators. As with other wildlife, it is likely that their coexistence in cities is also affecting their microbiota, promoting the development of antimicrobial resistance (AMR). This study aimed to assess the occurrence and patterns of AMR in commensal enteric Escherichia coli isolated from hedgehogs (n = 53) living in anthropogenic environments upon admission to a wildlife rescue center in Turin (Italy). The effects of hospitalization on the prevalence and trends of AMR were also assessed. Our results confirm that hedgehogs can harbor resistant E. coli upon admission, in particular against cefazolin (41.5%), ampicillin (37.7%), and enrofloxacin (22.6%). In addition, hospitalization promoted an increase in minimum inhibitory concentration (MIC) values of all antibiotics except imipenem, which led to a significant increase in E. coli that was resistant towards doxycycline, enrofloxacin, and trimethoprim-sulfamethoxazole. Admitted hedgehogs were also carriers of extended-spectrum beta-lactamase-producing E. coli (5.7%), whose presence increased during hospitalization (to 20.8%). These results highlight the role of hospitalizations longer than five days in the acquisition of AMR and suggest that European hedgehogs can become potential carriers of resistant E. coli following hospitalization. Full article

Background/Objectives: Increasing levels of antimicrobial resistance (AMR) have recently been observed at the human–domestic animal–wildlife interface. Wild birds have been identified as carriers of antimicrobial-resistant bacteria and serve as excellent biomarkers for epidemiological studies. This study assessed the current AMR presence in Eastern Spain’s commensal Escherichia coli isolated from free-ranging Bonelli’s eagles (Aquila fasciata). Methods: Nestlings and their nests were intensively sampled between 2022 and 2024 to determine their AMR profile and characterize E. coli. AMR testing was conducted using the broth microdilution method, following the European Committee on Antimicrobial Susceptibility Testing guidelines. Additionally, the presence of eaeA (intimin gene) and stx-1 and stx-2 (shiga toxins) was analyzed by real-time PCR to classify E. coli strains into enteropathogenic (EPEC) and Shiga-toxigenic (STEC) pathotypes. Results: Of all E. coli isolates, 41.7% were resistant to at least one antimicrobial, and 30% were multidrug-resistant. Only two strains were classified as EPEC and none as STEC. The highest resistance rates were observed for amoxicillin and tetracycline (19.6% each). Alarmingly, resistance to colistin and meropenem, last-resort antibiotics in human medicine, was also detected. Conclusions: Although the mechanisms of resistance acquisition remain unclear, transmission is likely to occur through the food chain, with synanthropic prey acting as intermediary vectors. These results highlight the role of Bonelli’s eagles as essential sentinels of environmental AMR dissemination, even in remote ecosystems. Strengthening One Health-based surveillance is necessary to address AMR’s ecological and public health risks in wildlife. Full article

Drosophilidae is a relatively small family within Diptera. However, species of this family occupy a wide range of ecological niches and are frequently found in synanthropic habitats. Additionally, some species are known agricultural pests. The dataset is based on collections of Drosophilidae from eleven regions of Russia. The dataset was uploaded to the GBIF platform in 2024. Published sources specifying exact localities and collection dates were also used. The database includes records dating back to 1867, with the majority of specimens collected by the authors between 2001 and 2024. Collection methods included net sweeping and bait trapping. The dataset contains 2830 occurrence records, with a total of 51,006 specimens of Drosophilidae studied. It includes data on 108 species from two subfamilies, covering 49 regions of Russia. Considering additional published sources, 188 species of Drosophilidae are currently known from Russia, with a complete species list provided. Among the most abundant species in the dataset, 10 species are represented by more than 1000 specimens: Drosophila obscura, Scaptodrosophila rufifrons, Drosophila melanogaster, Drosophila phalerata, Drosophila transversa, Drosophila kuntzei, Drosophila histrio, Drosophila testacea, Phortica semivirgo, and Drosophila immigrans. Conversely, 39 species are represented by fewer than 10 specimens in the dataset. Regarding ecological groupings, the most dominant groups are xylosaprobionts (39 species, 40.6%) and mycophages (30 species, 31.3%). Notably, in 2017, the quarantine pest Drosophila suzukii was detected in the European part of Russia. The current knowledge of the Drosophilidae fauna in Russia remains insufficient. Of the 15 regions, only one or two localities are represented in the dataset. The distribution limits and range boundaries of many species remain unknown. Moreover, the local faunas of more than half of Russia’s regions remain unexplored. Full article

For the first time, the numerous scattered data on birds (wild and domestic) have been collected based on their medieval bone remains discovered on the modern territory of the Republic of Bulgaria. The collected information is about a total of 37 medieval settlements from the time of the First and Second Bulgarian Empires. Among the settlements studied are both the two medieval Bulgarian capitals (Pliska and Veliki Preslav), as well as other cities, smaller settlements, military fortresses, monasteries, and inhabited caves. The data refer to a total of 48 species of wild birds and 6 forms of domestic birds of 11 avian orders: Accipitriformes, Anseriformes, Ciconiiformes, Columbiformes, Falconiformes, Galliformes, Gruiformes, Otidiformes, Passeriformes, Pelecaniformes, and Strigiformes. The established composition of wild birds amounts to over one tenth (to 11.5%) of the modern avifauna in the country. Five of the established species (10.4%) have disappeared from the modern nesting avifauna of the country—the bearded vulture, the great bustard, the little bustard, the gray crane, and the saker falcon (the latter two species have reappeared as nesters in the past few years). First Bulgarian Empire (681–1018): Investigated settlements—22. Period covered—five centuries (7th to 11th c.). Found in total: at least 44 species/forms of birds, of which 39 species of wild birds and 5 forms of poultry. Second Bulgarian Empire (1185–1396): Investigated settlements—15. Period covered—3 centuries (12th to 14th c.). Found in total: at least 39 species/forms of birds, of which 33 species of wild birds and 6 forms of poultry. The groups of raptors, water, woodland, openland, synanthropic and domestic birds were analyzed separately. The conclusion was made that during the two periods of the Middle Ages, birds had an important role in the material and spiritual life of the population of the Bulgarian lands. Birds were mainly used for food (domestic birds), although some were objects of hunting. No traces of processing were found on the bones. Birds were subjects of works of applied and monumental art. Their images decorated jewelry, tableware, walls of buildings and other structures. Full article

Bats serve as key ecological reservoirs of diverse microbial communities, including emerging viruses and antibiotic resistance genes. This study investigates the intestinal microbiota of two insectivorous bat species, Nyctalus noctula and Vespertilio murinus, at the Rostov Bat Rehabilitation Center in Southern Russia using whole metagenome shotgun sequencing. We analyzed taxonomic composition, functional pathways, antibiotic resistance genes, and virulence factors. Densoviruses, especially those closely related to Parus major densovirus, were the most dominant viral sequences identified. Metagenome-assembled densovirus genomes showed high sequence similarity with structural variations and clustered phylogenomically with viruses from mealworms and birds, reflecting both dietary origins and the potential for vertebrate infection. Functional profiling revealed microbial pathways associated with cell wall biosynthesis, energy metabolism, and biofilm formation. A total of 510 antibiotic resistance genes, representing 142 unique types, mainly efflux pumps and β-lactamases, were identified. Additionally, 870 virulence factor genes were detected, with a conserved set of iron acquisition systems and stress response regulators across all samples. These findings highlight the ecological complexity of bat-associated microbiota and viromes and suggest that synanthropic bats may contribute to the circulation of insect-associated viruses and antimicrobial resistance in urban settings. Full article

Hibernation in mammals entails profound physiological changes that are known to impact host-associated microbial communities, yet its effects on the gut microbiota of synanthropic bats remain underexplored. In this study, we investigated the gut bacterial composition and diversity of Nyctalus noctula before and during hibernation using high-throughput 16S rRNA amplicon sequencing. Fecal samples from individually banded bats were collected under controlled conditions at a rehabilitation center and analyzed for alpha and beta diversity, as well as differential taxonomic abundance. Hibernation was associated with a marked reduction in microbial diversity according to the Shannon and Simpson indices and a distinct restructuring of gut communities based on the Bray–Curtis dissimilarity index. Active bats exhibited a diverse microbiota enriched in facultative anaerobes, including Lactococcus, Enterococcus, and Escherichia–Shigella, while hibernating individuals were dominated by obligate anaerobes, such as Romboutsia and Paeniclostridium. These findings suggest a contraction and functional specialization of the gut microbiota during torpor, potentially reflecting adaptations to fasting, hypothermia, and reduced gut motility. Our results demonstrate that the bat’s gut microbiome is highly responsive to physiological status and underscore the importance of microbial ecology for understanding the host’s energy balance and health under seasonal contexts. Full article

Rodents represent the most diverse order of mammals, comprising over 2200 species and nearly 42% of global mammalian biodiversity. They are major reservoirs of zoonotic pathogens, including viruses, bacteria, protozoa, and fungi, and are particularly effective at transmitting diseases, especially synanthropic species that live in close proximity to humans. As of April 2025, approximately 15,205 rodent-associated viruses have been identified across 32 viral families. Among these, key zoonotic agents belong to the Arenaviridae, Hantaviridae, Picornaviridae, Coronaviridae, and Poxviridae families. Due to their adaptability to both urban and rural environments, rodents serve as efficient vectors across diverse ecological landscapes. Environmental and anthropogenic factors, such as climate change, urbanization, deforestation, and emerging pathogens, are increasingly linked to rising outbreaks of rodent-borne diseases. This review synthesizes current knowledge on rodent-borne viral zoonoses, focusing on their taxonomy, biology, host associations, transmission dynamics, clinical impact, and public health significance. It underscores the critical need for early detection, effective surveillance, and integrated control strategies. A multidisciplinary approach, including enhanced vector control, improved environmental sanitation, and targeted public education, is essential for mitigating the growing threat of rodent-borne zoonoses to global health. Full article

Highly pathogenic avian influenza (HPAI) is a highly contagious disease of domestic, synanthropic, and wild birds that has demonstrated a sharp rise globally since 2020. This study intends to examine environmental and demographic factors most significantly associated with HPAI (H5N1 and H5N8) outbreaks in Kazakhstan, 2020–2024, and to identify areas of potential underreporting of the disease. Two ecological niche models were developed, namely an “occurrence model” (considering climatic and environmental factors influencing the likelihood of HPAI occurrence) and a “reporting model” (that assesses the probability of disease reporting based on human and poultry population demography). Both models were trained using outbreak locations in countries neighboring Kazakhstan (Afghanistan, China, Hong Kong, Iran, Iraq, Pakistan and Russia), and then tested using the HPAI outbreak locations in Kazakhstan. Results suggested a good fit for both models to Kazakhstani outbreaks (test AUC = 0.894 vs. training AUC = 0.915 for “occurrence model”, and test AUC = 0.869 vs. training AUC = 0.872 for “reporting model”). A cluster of high occurrence-to-reporting ratio was detected in the south-western region of Kazakhstan, close to the Caspian Sea, suggesting a need for enhancing surveillance efforts in this zone as well as in some other areas of Pavlodar, Northern Kazakhstan, Western Kazakhstan, Qyzylorda, and Eastern Kazakhstan. Results presented here will help inform the design and implementation of control strategies for HPAI in Kazakhstan with the ultimate goal of promoting disease prevention and control in the country. Full article

Although the SARS-CoV-2 pandemic primarily affected the human population, the virus has also been detected in various animal species worldwide, raising concerns about its potential to establish new animal reservoirs. This study aimed to investigate the presence of SARS-CoV-2 in non-human primates (NHPs) and synanthropic small mammals (SSMs) in the Jequitinhonha Valley and Northern Minas Gerais, Brazil. Between October 2021 and October 2023, 119 animals were sampled, 82 NHPs and 37 SSMs, across 22 municipalities. A total of 342 biological samples—including oral and nasal swabs, lungs, livers, spleens, blood, and feces—were collected and analyzed using RT-qPCR, while 37 serum samples were submitted to neutralization tests. Despite the diversity of sampled species, habitats, and biological materials, no evidence of SARS-CoV-2 infection or specific antibodies was detected in any of the individuals tested. The results suggest that NHPs and SSMs in these regions did not act as reservoirs for SARS-CoV-2 during the study period. This finding is particularly relevant given the high synanthropy of species such as Callithrix penicillata (black-tufted marmoset) and Rattus rattus (black rat), which frequently interact with human populations. Our study underscores the importance of integrating animal, human, and environmental health perspectives under a One Health framework to monitor emerging zoonotic threats. By providing baseline data on SARS-CoV-2 dynamics in wildlife, we emphasize the need for ongoing ecological and epidemiological surveillance to assess potential spillover events and their implications for biodiversity and public health in Brazil. Full article

Chrysomya megacephala (Diptera: Calliphoridae), commonly referred to as the oriental latrine fly, is a synanthropic blowfly species frequently associated with decomposing organic matter. This study sought to investigate the influence of various feeding substrates and temperature conditions, specifically constant temperatures of 15, 25, 35 °C, and variable temperatures averaging 23.31 °C, on the gut microbiome of C. megacephala. The microbiome analysis was conducted using the Illumina HiSeq platform for 16S rRNA gene sequencing in Changsha, China. Across all experimental conditions, the gut microbiome of C. megacephala yielded 1257 operational taxonomic units (OTUs), which were categorized into 26 phyla, 72 classes, 165 orders, 270 families, 516 genera, and 794 species. The study showed significant differences in the gut microbiome of C. megacephala between different feeding sources and temperature conditions across the lifespan. Low temperature had the potential to reduce the proportion abundance of bacterial communities in the gut microbiome, while high and variable temperature increased them. Metabolism was the main predicted function with diverse phenotypic characters in the gut microbiota of C. megacephala. The presence of diverse bacterial phenotypes in the gut microbiome of C. megacephala highlights its significant interest for medicine and offers promising applications in industry and agriculture. Full article

The urbanization and the expansion of human settlements led to the adaptation of many animal species to living close to humans, often using buildings for roosting. Panel buildings are particularly attractive to rock-dwelling animals such as swifts, swallows, pigeons, and bats due to their numerous cracks and crevices. The abundance of these structures in Eastern Europe has led to the establishment of numerous bird and bat colonies in the cities. However, the recent renovation and insulation of these buildings, while beneficial to residents, threatens the roosts. Construction workers are sometimes unaware of animal presence and inadvertently destroy nests or colonies. Rapid assessments before renovation are essential to rescue individuals and ensure the planning of alternative roosts for bats and birds. We conducted a pilot survey of 61 residential buildings in five municipalities in Bulgaria: Razgrad, Popovo, Haskovo, Dimitrovgrad, and Bobov Dol, to assess bird and bat biodiversity. We performed field assessments using direct observation, thermal cameras, ultrasonic detection, sunset counts, and endoscopic cameras. The most commonly detected bird species were the house martin, barn swallow, common swifts, the Eurasian jackdaw, pigeons, and sparrows. The most commonly detected bat species were the common pipistrelle, noctule, and Kuhl’s pipistrelle. Additionally, we discuss the specifics of the “soviet-type” buildings as nesting facilities for pigeons and the impact of the pigeons on the “micro ecology” of the blocks. Our study aimed to guide conservation actions and awareness during the expanding renovation efforts of old buildings in Bulgaria. Full article

Urbanization replaces natural vegetation for city expansion, impacting environmental and climatic variables that affect the health of the human population and fauna. These changes affect important groups such as birds, given their greater sensitivity to anthropogenic alterations, especially when we understand these effects on a large scale, considering countries such as Brazil, which represents the third country with the greatest diversity of bird species in the world. Conversely, green spaces like urban parks, tree-lined avenues, and riparian forests seem to foster biodiversity conservation. Here, we analyze the effects of vegetation on bird communities and bird–plant interactions in urban riparian areas that have undergone ecological restoration. The study was carried out between January and October 2019 in two restored urban areas of Uberlândia, Brazil. Results showed that the richness of birds observed between the two areas was Praia Clube (n = 86) and Parque Linear Rio Uberabinha (n = 80). The most representative trophic guilds in the areas, with the highest proportion in their relative abundances during both seasons, were granivores, omnivores, insectivores, and frugivores. Composition varied significantly between areas as a function of the plant community, particularly when considering the interaction between season and area (ANOSIM: R = 0.19; Stress = 0.10; p = 0.008). In environments dominated by generalist and synanthropic species (Eared Dove, Picazuro Pigeon), effective planning and management of green areas are crucial. It is important to acknowledge that certain bird species depend on specific habitats, such as riparian forests, and that specific plant species within these areas are vital for specialized bird species, such as species endemic to the Brazilian Savanna or Cerrado and restricted to Brazil (White-striped Warbler) and species in vulnerable categories globally (Bare-faced Curassow). Therefore, restoration efforts in degraded areas should be carefully planned to restore interactions and conserve biodiversity effectively. Full article