Super- and low-shedding phenomena have been observed in genetically homogeneous hosts infected by a single bacterial strain. To decipher the mechanisms underlying these phenotypes, we conducted an experiment with chicks infected with Salmonella Enteritidis in a non-sterile isolator, which prevents bacterial transmission between animals while allowing the development of the gut microbiota. We investigated the impact of four commensal bacteria called Mix4, inoculated at hatching, on chicken systemic immune response and intestinal microbiota composition and functions, before and after Salmonella infection. Our results revealed that these phenotypes were not linked to changes in cell invasion capacity of bacteria during infection. Mix4 inoculation had both short- and long-term effects on immune response and microbiota and promoted the low-shedder phenotype. Kinetic analysis revealed that Mix4 activated immune response from day 4, which modified the microbiota on day 6. This change promotes a more fermentative microbiota, using the aromatic compounds degradation pathway, which inhibited Salmonella colonization by day 11 and beyond. In contrast, control animals exhibited a delayed TNF-driven pro-inflammatory response and developed a microbiota using anaerobic respiration, which facilitates Salmonella colonization and growth. This strategy offers promising opportunities to strengthen the barrier effect against Salmonella and possibly other pathogens.
- Klíčová slova
- Salmonella, carrier-state, chicken, excretion, immune response, microbiota, super-shedder, virulence,
- MeSH
- Bacteria * imunologie klasifikace genetika MeSH
- kur domácí imunologie mikrobiologie MeSH
- nemoci drůbeže * mikrobiologie imunologie prevence a kontrola MeSH
- Salmonella enteritidis * imunologie růst a vývoj fyziologie MeSH
- salmonelová infekce u zvířat * imunologie mikrobiologie prevence a kontrola MeSH
- střevní mikroflóra * imunologie MeSH
- symbióza MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Urban environments exert strong pressures on animal behavior, leading to altered fear responses to humans. Species with a longer history of urban presence and greater tolerance to urban environments are expected to show reduced fear responses towards humans. Here, we examined whether avian flight initiation distance (a proxy of fear)-the distance at which a bird flees from an approaching human-is associated with a species' timing of urban colonization (i.e., when it has started to breed in urban areas) and with present-day urban tolerance (i.e., how common it is in the city). Unlike previous studies which paired avian fear responses and urbanization timing from different regions, we collected both in the same city (Prague, Czechia), minimizing regional differences in urban history and providing a more rigorous test of the link between urbanization timing and avian fear responses. RESULTS: Using standardized data from 4420 flight initiation distance observations across 68 species, we applied Bayesian phylogenetic mixed models while controlling for ecological and contextual variables. We found that species with a longer urban history (i.e., earlier timing of urban colonization) showed significantly shorter flight initiation distances, suggesting reduced fear responses. In contrast, present-day urban tolerance based on breeding commonness was not related to flight initiation distance variation. CONCLUSIONS: We found that the timing of urban colonization better predicts reduced fear of humans in birds than present-day urban tolerance, emphasizing the role of long-term behavioral filtering and/or selection in shaping urban wildlife behavior. By explicitly separating urbanization time from contemporary urban commonness within a single city and analyzing individual-level fear responses, our study shows that earlier urban colonizers exhibit consistently shorter escape distances, reflecting cumulative long-term processes rather than short-term plasticity alone. These findings highlight the importance of incorporating urban colonization history into behavioral ecology and urban wildlife management frameworks.
- Klíčová slova
- Birds, Flight initiation distance, Monitoring, Urban habitats, Urban tolerance, Urbanization time,
- MeSH
- Bayesova věta MeSH
- časové faktory MeSH
- let zvířat MeSH
- lidé MeSH
- ptáci * fyziologie MeSH
- strach * MeSH
- urbanizace * MeSH
- velkoměsta MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
- velkoměsta MeSH
Many species are currently experiencing range shifts in response to changing environmental conditions with potentially serious genetic consequences. Repeated founder events and strong genetic drift are expected to erode genetic variation at the range front, reducing adaptive potential and slowing or even halting the expansion. However, the severity of these consequences for common and highly mobile species undergoing environment-driven range shifts (c.f. invasions) is less clear. Here, we combined historical observations and contemporary movement data of the common reed warbler (Acrocephalus scirpaceus) with genomic evidence from across its European breeding range to (1) infer the origin and (2) quantify the genetic consequences of a recent and rapid northward range expansion. Although there were no reductions in levels of nucleotide diversity or allelic richness, nor a signal of founder effect in the directionality index (ψ), our combined dataset approach was able to infer an expansion origin from the southwest. Furthermore, we found that private allelic richness retained a slight but significant linear decline along the colonisation route. These results suggest that high dispersal capabilities can allow even philopatric species to avoid the loss of genetic diversity during rapid range expansions. Nevertheless, if multiple lines of evidence enable identification of an expansion pathway, we may still detect genetic signals of expansion.
- Klíčová slova
- birds, phylogeography, population genomics, range shifts,
- MeSH
- alely MeSH
- efekt zakladatele * MeSH
- genetická variace * MeSH
- genetický drift MeSH
- populační genetika * MeSH
- rozšíření zvířat * MeSH
- zpěvní ptáci * genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Evropa MeSH
The Triad framework seeks to balance the economic and ecological functions in forested landscapes by combining intensively, extensively, and unmanaged areas, assuming a higher support to biodiversity in extensively rather than in intensively managed forests. We quantified the effects of Triad zoning on biodiversity in (sub)montane eutrophic European beech forests. Using a European-wide multitaxon database and a "virtual" landscape approach (i.e., by resampling empirical data), we evaluated how the proportion of Triad management categories affected the landscape-level species diversity of birds, saproxylic beetles, vascular plants, epiphytic bryophytes, lichens, and wood-inhabiting fungi, as well as multitaxonomic diversity. The results varied greatly among taxonomic groups. Multitaxonomic diversity peaked in landscapes composed of 60% unmanaged and 40% intensively managed forests. While intensive management can benefit some taxa through the creation of open habitats, unmanaged forests are the backbone of biodiversity conservation, underlining the need to safeguard the remaining old-growth forests under natural dynamics, and to extend the current area of unmanaged forests in Europe. Extensive forest management, however, did not contribute to biodiversity conservation as expected. As withdrawing such a high proportion of European forest landscapes from management is unfeasible given the increasing demand for timber, efforts are needed to increase the presence of structural features supporting biodiversity into extensively managed forests.
- Klíčová slova
- biodiversity conservation, forest management, forestry, gamma diversity, landscape planning,
- MeSH
- biodiverzita * MeSH
- buk (rod) MeSH
- ekosystém MeSH
- lesnictví * metody MeSH
- lesy * MeSH
- ptáci MeSH
- zachování přírodních zdrojů * metody MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Evropa MeSH
Understanding the transmission routes of high-pathogenicity avian influenza (HPAI) is crucial for developing effective control measures to prevent its spread. In this context, windborne transmission, the idea that the virus could travel through the air over considerable distances, is a contentious concept, and documented cases have been rare. Here, though, we provide genetic evidence supporting the feasibility of windborne transmission. During the 2023-24 HPAI season, molecular surveillance identified identical H5N1 strains among a cluster of unrelated commercial farms about 8 km apart in the Czech Republic. The episode started with the abrupt mortality of fattening ducks on one farm. This was followed by disease outbreaks at two nearby high-biosecurity chicken farms. Using genetic, epizootiological, meteorological and geographical data, we reconstructed a mosaic of events strongly suggesting wind was the most probable mechanism of infection transmission between poultry in at least two independent cases. By aligning the genetic and meteorological data with critical outbreak events, we determined the most likely time window during which the transmission occurred and inferred the sequence of infected houses at the recipient sites. Our results suggest that the contaminated plume emitted from the infected fattening duck farm was the critical medium of HPAI transmission, rather than the dust generated during depopulation. Furthermore, our results also strongly implicate the role of confined mechanically-ventilated buildings with high population densities in facilitating windborne transmission and propagating virus concentrations below the minimum infectious dose at the recipient sites. These findings underscore the importance of considering windborne spread in future outbreak mitigation strategies.
- MeSH
- drůbež virologie MeSH
- epidemický výskyt choroby * veterinární MeSH
- fylogeneze MeSH
- kachny virologie MeSH
- kur domácí virologie MeSH
- nemoci drůbeže * přenos epidemiologie virologie MeSH
- ptačí chřipka u ptáků * přenos epidemiologie virologie MeSH
- virus chřipky A, podtyp H5N1 * genetika patogenita MeSH
- vítr * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika epidemiologie MeSH
Pathological changes involving the feathers of raptors include the pinching-off syndrome (POS). The disease is manifested by defective feather growth, wherein the young, vascularized remiges and rectrices are twisted and prematurely fall out. Upon examination, the feathers that are prematurely shed are found to have a marked constriction at the base of the shaft. Remiges and rectrices reach just 1/2 half to 2/3 thirds of their normal length, after which the blood supply is reduced and dystrophic feathers are dropped. Feather development deteriorates further, and new flight feathers are dystrophic and become progressively shorter with each new feather generation. Affected birds are unable to fly. The first survey of POS in white-tailed eagles (WTE; Haliaeetus albicilla) focused on 33 cases in Germany, Poland, the Czech Republic, the United Kingdom, and Russia from 1975 to 2006 (J Avian Med Surg. 2007;21:103-105). We revealed 43 new cases from 2007 to 2024, identifying these in Germany (n = 15), Poland (n = 9), the Czech Republic (n = 10), Russia (n = 8), and Kazakhstan (n = 1). In addition, 3 cases in Poland, 2 in the Czech Republic, and 1 in both Russia and Kazakhstan were identified from 1999 to 2006 but not published previously. In total, we report 50 new clinical cases of POS in WTE. The investigation thus far into the cause of POS has failed to determine an etiological agent. Based on the association of a higher prevalence of POS in an area occupied by a WTE population with a different genetic structure compared with other WTE populations and based on 6 family cases registered, we support a hypothesis for a genetic cause of POS.
- Klíčová slova
- avian, birds of prey, disease, feather, raptors, rectrices, remiges,
- MeSH
- Accipitridae * MeSH
- nemoci ptáků * patologie epidemiologie MeSH
- peří * patologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Urbanization with a rapid expansion of the road network disrupts ecological processes, fragmenting the landscape, and reducing biodiversity. The frequent machine and human activities involved in road construction led to significant pressure on ecosystems. However, research on the impact of roading building processes in different stages remains lacking information. We performed a bird census for a new highway construction, the SE-40 ring road in Seville, with three-stages: a) active works, b) suspended works stage surrounding, and c) control stage in a natural condition. We analyzed similarities in community composition and bioindicators using the Indicator Value (IndVal) analysis between different stages. Additionally, we calculated several avian biodiversity metrics, including bird species richness, abundance, biodiversity, and diet-specialist species richness (DSR) and abundance (TAB). Road construction significantly impacted species composition (NMDS, ANOSIM p < 0.001, R2 = 0.1692); both active (P. adjusted = 0.006) and suspended work (P. adjusted = 0.009) stages display differences compared to the control group. The number of species and bioindicator increases, but diet-specialist species decreased, from active works (bioindicator = 3; mean TAB = 6; mean DSR = 19) to control group (4; 4.89; 12.61) to suspended works (5; 5.67; 14.89), reflecting a higher homogeneity during the active works with lowest biodiversity (mean Shannon = 2.69 and Simpson = 0.92). Our findings highlight the overlooked value of suspended works as provisional habitats for bird assemblages, suggesting that areas with intensive human activity need specific biodiversity monitoring and implications for conservation efforts. Rigorous specific biodiversity monitoring is essential to mitigate long-term impacts and inform adaptive road planning strategies.
- Klíčová slova
- Anthropic pressure, Avian assemblages, Bird conservation, Road network, Spain,
- MeSH
- biodiverzita * MeSH
- ekosystém MeSH
- lidé MeSH
- ptáci * MeSH
- urbanizace MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Across the world, human (anthropophonic) sounds add to sounds of biological (biophonic) and geophysical (geophonic) origin, with human contributions including both speech and technophony (sounds of technological devices). To characterize society's contribution to the global soundscapes, we used passive acoustic recorders at 139 sites across 6 continents, sampling both urban green spaces and nearby pristine sites continuously for 3 years in a paired design. Recordings were characterized by bird species richness and by 14 complementary acoustic indices. By relating each index to seasonal, diurnal, climatic and anthropogenic factors, we show here that latitude, time of day and day of year each predict a substantial proportion of variation in key metrics of biophony-whereas anthropophony (speech and traffic) show less predictable patterns. Compared to pristine sites, the soundscape of urban green spaces is more dominated by technophony and less diverse in terms of acoustic energy across frequencies and time steps, with less instances of quiet. We conclude that the global soundscape is formed from a highly predictable rhythm in biophony, with added noise from geophony and anthropophony. At urban sites, animals experience an increasingly noisy background of sound, which poses challenges to efficient communication.
This study investigated the combined effects of transport distance and season on poultry mortality rates (end-of-lay hens, broiler chickens, turkeys, and ducks) during transport to slaughterhouses. Retrospective data analysis included all poultry shipments from Czech farms to Czech slaughterhouses from 2017 to 2023. In total, 11,503,789 end-of-lay hens, 807,874,546 broiler chickens, 1,075,070 turkeys, and 28,012,184 ducks were transported in the monitored period. The highest mortality rates were observed in laying hens (1.212 %) and broiler chickens (0.884 %) during winter when transported over very long distances (301 km and more). For ducks, peak mortality (0.589 %) was found during summer transport over the distances of 201-300 km (no ducks were transported for longer distances). In turkeys, the highest mortality (0.598 %) was recorded in autumn over distances of 51-100 km, likely due to the limited number of birds transported over longer distances (97 % of turkeys transported within 100 km) and during extreme-temperature seasons. These findings highlight the need for species-specific transport management strategies, particularly for vulnerable categories such as end-of-lay hens and broiler chickens.
- Klíčová slova
- Broiler, DOA, Duck, Hen, Turkey,
- MeSH
- chov zvířat MeSH
- doprava * MeSH
- jatka MeSH
- kachny * fyziologie MeSH
- krocani * fyziologie MeSH
- kur domácí * fyziologie MeSH
- mortalita * MeSH
- retrospektivní studie MeSH
- roční období MeSH
- zvířata MeSH
- Check Tag
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
Automated detection of dead chickens is essential for enhancing biosecurity, animal welfare, and operational efficiency in poultry farms. This study evaluates the performance of YOLOv8n, YOLOv9c, YOLOv10n, and YOLOv11n for detecting dead chickens in cage-free poultry farms. A synthetic dataset of 3413 images was created by compositing manually annotated images of dead and healthy chickens into realistic stall backgrounds to simulate real farm conditions. The models were assessed using standard object detection metrics (precision, recall, and mean average precision (mAP) at IoU thresholds of 0.5 and 0.5-0.95) alongside computational efficiency indicators including inference speed, frames per second (FPS), model size, and training time. YOLOv9c achieved the highest detection accuracy (mAP@50 = 0.983, mAP@50-95 = 0.93), making it the most reliable for minimising false positives and missed detections. YOLOv11n delivered the fastest inference speed (2.8 ms/frame, ∼357 FPS), making it more suitable for real-time applications. These results underscore the importance of selecting a YOLO model based on farm-specific operational constraints. YOLOv9c is recommended for accuracy-critical tasks, YOLOv11n for real-time monitoring, and YOLOv8n or YOLOv10n for resource-limited deployments. Comparative analysis with earlier YOLO models (YOLOv3-YOLOv7) shows that newer versions improve both detection reliability and processing speed. This work contributes a performance benchmark to guide AI-based poultry monitoring and highlights future directions, including real-world deployment and validation under live farm conditions.
- Klíčová slova
- Animal welfare, Computer vision, Object detection, Poultry farm monitoring, Smart farming,
- MeSH
- chov zvířat * metody MeSH
- deep learning * MeSH
- kur domácí * MeSH
- nemoci drůbeže * diagnóza mortalita MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
