Detection of a novel bacterium of the genus Midichloria (family Midichloriaceae) in avian-borne Hyalomma marginatum ticks and their trans-Saharan migratory hosts

Introduction: Ticks are haematophagous ectoparasites of vertebrates habitually parasitizing avian species, which may contribute to tick dispersal across continents during migrations (Hasle 2013; Altizer et al., 2011). Midichloria bacteria can be transmitted to the vertebrate host during the tick bite (Bazzocchi et al., 2013; Serra et al., 2018). Although many avian species are common hosts of ticks harbouring Midichloria (e.g. Ixodes, Hyalomma), the circulation of this bacterium in birds has never been investigated. The aims of this study are: 1) evaluate the presence of Midichloria DNA in H. marginatum ticks and blood collected from trans-Saharan migratory birds; 2) quantify Midichloria bacteria in ticks through a novel quantitative PCR (qPCR).Material and methods: A total of 256 H. marginatum ticks and 97 blood samples were collected from three different migratory species (Phoenicurus phoenicurus, Saxicola rubetra and Sylvia communis) on Ventotene Island (Central Italy) and DNAs were extracted. A nested-PCR targeting the 16S rRNA gene of Midichloria was used to detect bacterial presence. Subsequently, primers targeting the gyrB gene of Midichloria and the cal gene of H. marginatum were designed and used in a qPCR for Midichloria quantification. Results were expressed as gyrB/cal copy numbers ratio.Results and discussion: 94% of Hyalomma ticks harbored DNA of Midichloria belonging to the monophylum associated with ticks, while the bacterial DNA was detected in 44.3% of blood samples. Furthermore, engorged ticks showed significantly higher bacteria load than unengorged ticks (Table 1; Wilcoxon sum-rank test: z=3.14; p=0.0017), similarly to what has been observed for M. mitochondrii in I. ricinus ticks.Conclusions: This work provides evidence for the presence of circulating Midichloria DNA in long-distance migratory birds, suggesting an enhanced worldwide spread of these bacteria across haematophagous ectoparasite populations. Future studies are necessary to increase the knowledge of Midichloria role in the biology of this tick species

Scalable software framework for real-time data processing in the railway environment

Background: Ticks are obligate haematophagous ectoparasites of vertebrates and frequently parasitize avian species that can carry them across continents during their long-distance migrations. Ticks may have detrimental effects on the health state of their avian hosts, which can be either directly caused by blood-draining or mediated by microbial pathogens transmitted during the blood meal. Indeed, ticks host complex microbial communities, including bacterial pathogens and symbionts. Midichloria bacteria (Rickettsiales) are widespread tick endosymbionts that can be transmitted to vertebrate hosts during the tick bite, inducing an antibody response. Their actual role as infectious/pathogenic agents is, however, unclear. Methods: We screened for Midichloria DNA African ticks and blood samples collected from trans-Saharan migratory songbirds at their arrival in Europe during spring migration. Results: Tick infestation rate was 5.7%, with most ticks belonging to the Hyalomma marginatum species complex. Over 90% of Hyalomma ticks harboured DNA of Midichloria bacteria belonging to the monophylum associated with ticks. Midichloria DNA was detected in 43% of blood samples of avian hosts. Tick-infested adult birds were significantly more likely to test positive to the presence of Midichloria DNA than non-infested adults and second-year individuals, suggesting a long-term persistence of these bacteria within avian hosts. Tick parasitism was associated with a significantly delayed timing of spring migration of avian hosts but had no significant effects on body condition, whereas blood Midichloria DNA presence negatively affected fat deposits of tick-infested avian hosts. Conclusions: Our results show that ticks effectively transfer Midichloria bacteria to avian hosts, supporting the hypothesis that they are infectious to vertebrates. Bird infection likely enhances the horizontal spread of these bacteria across haematophagous ectoparasite populations. Moreover, we showed that Midichloria and tick parasitism have detrimental non-independent effects on avian host health during migration, highlighting the complexity of interactions involving ticks, their vertebrate hosts, and tick-borne bacteria

Clinical features and outcomes of elderly hospitalised patients with chronic obstructive pulmonary disease, heart failure or both

Background and objective: Chronic obstructive pulmonary disease (COPD) and heart failure (HF) mutually increase the risk of being present in the same patient, especially if older. Whether or not this coexistence may be associated with a worse prognosis is debated. Therefore, employing data derived from the REPOSI register, we evaluated the clinical features and outcomes in a population of elderly patients admitted to internal medicine wards and having COPD, HF or COPD + HF. Methods: We measured socio-demographic and anthropometric characteristics, severity and prevalence of comorbidities, clinical and laboratory features during hospitalization, mood disorders, functional independence, drug prescriptions and discharge destination. The primary study outcome was the risk of death. Results: We considered 2,343 elderly hospitalized patients (median age 81 years), of whom 1,154 (49%) had COPD, 813 (35%) HF, and 376 (16%) COPD + HF. Patients with COPD + HF had different characteristics than those with COPD or HF, such as a higher prevalence of previous hospitalizations, comorbidities (especially chronic kidney disease), higher respiratory rate at admission and number of prescribed drugs. Patients with COPD + HF (hazard ratio HR 1.74, 95% confidence intervals CI 1.16-2.61) and patients with dementia (HR 1.75, 95% CI 1.06-2.90) had a higher risk of death at one year. The Kaplan-Meier curves showed a higher mortality risk in the group of patients with COPD + HF for all causes (p = 0.010), respiratory causes (p = 0.006), cardiovascular causes (p = 0.046) and respiratory plus cardiovascular causes (p = 0.009). Conclusion: In this real-life cohort of hospitalized elderly patients, the coexistence of COPD and HF significantly worsened prognosis at one year. This finding may help to better define the care needs of this population

Nest-boxes alter the reproductive ecology of urban cavity-nesters in a species-dependent way

Human-provided nesting shelters such as nest-boxes mitigate the shortage of natural breeding sites. Since artificial nests are not where animals evolved and optimised their reproductive performance, it remains inconclusive if these are adequate substitutes, ensuring equivalent fitness returns while breeding. In particular, most knowledge on the ecology of cavity-nesting birds comes from nest-box populations, but no study has directly compared fitness consequences of breeding inside nest-boxes in relation to natural cavities in cities. We directly compare the reproductive performance, life-history trait variation and fitness consequences for two small passerines, blue and great tits, breeding in nest-boxes as opposed to natural cavities in an urban deciduous forest. We use a quasi-experimental setting to comprehend the conservation potential of these artificial cavities and to support/question generalisations stemming from nest-box studies. We show that the effects of cavity type vary between species: in blue tits, fitness proxies were negatively affected by nest-boxes (lower fledging success and fledgling numbers, longer time spent in the nest and later fledging date relative to natural cavities), while in great tits, the fitness proxies were unaffected by cavity type. Importantly, we detected accelerated incubation in both species breeding in nest-boxes. No differences in pre-hatching traits (lay date, clutch size, hatching rates) between cavity types suggest that the fitness deterioration occurred because of post-hatching effects. We highlight the ecological importance of old-growth tree stands, providing natural cavities for city-breeding animals and the need for quantifying alterations of reproductive ecology in other taxa using human-provided nests. Owing to the detected cavity type-dependent variation in reproductive performance, we support the criticism regarding the unconditional extrapolation of evolutionary and ecological interpretations of nest-box studies to general populations

Microclimate shifts in nest-boxes and natural cavities throughout reproduction

Animals breeding in nest-boxes experience nesting environments in which they did not originally evolve. Despite the central importance of nesting microclimate for offspring fitness, little is known about the thermal properties of human-provided nest sites compared to natural ones. In particular, comparisons with offspring in the nest are lacking. Here, we compare microclimate (temperature and absolute humidity) from the onset of breeding, thus starting with nest-site choice and ending with the post-fledging stage, quantified in natural cavities and nest-boxes used by several species of hollow-nesting birds in a temperate deciduous forest. We confirm that across all nesting stages, nest-boxes were thermally unstable when compared to natural cavities, with higher temperature maximums, larger amplitudes and worse insulation from maximum ambient temperatures relative to natural cavities. Surprisingly, as average humidity of natural cavities was previously shown to be higher than in nest-boxes, in the presence of actively thermoregulating young, nest-boxes were more humid than natural cavities. When offspring were in the nest, internal microclimatic shifts were mitigated three times more effectively in natural cavities than in nest-boxes (in terms of mean daily differences from ambient temperature). Artificial cavity microclimate is likely to amplify the adverse effects of projected temperature increases by compromising thermoregulation of developing animals. We stress that conservation efforts should focus on the protection of areas offering natural breeding-hollows to reduce the potential impacts of climate change on breeding animals

Extra‐pair paternity, breeding density, and synchrony in natural cavities versus nestboxes in two passerine birds

International audienceMost of what is known about extra-pair paternity in hole-nesting birds derives from studies using artificial nesting sites, such as nestboxes. However, it has rarely been investigated whether inference drawn from breeding events taking place in nestboxes matches what would be observed under natural conditions, that is, in natural cavities. We here report on a variation in promiscuity in blue tits and great tits nesting in natural cavities and nestboxes in an urban forest in Warsaw, Poland. Specifically, we tested whether local breeding density, local breeding synchrony, and extra-pair paternity (inferred from SNP data generated with a high-throughput genotyping by sequencing method) differed between birds nesting in natural cavities and nestboxes. In both blue tits and great tits, the frequency of extra-pair paternity was similar between the two cavity types. In blue tits, we observed shorter nearest neighbor distance, higher neighbor density, and higher synchronous neighbor density (i.e., density of fertile females) in nestboxes relative to natural cavities. No such pattern was found in great tits. Moreover, we detected a positive relationship between the proportion of extra-pair offspring in the nest and neighbor density around the nest in blue tits. Our results revealed that the provisioning of nestboxes did not change rates of extra-pair paternity, suggesting that conclusions drawn from nestbox studies might adequately represent the natural variation in extra-pair matings in some species or sites. However, the observed differences in spatiotemporal components of breeding dynamics highlight the fact that these parameters should be carefully considered when comparing mating behavior across studies and/or sites

Preserving avian blood and DNA sampled in the wild : a survey of personal experiences

Collecting and storing biological material from wild animals in a way that does not deteriorate DNA quality for subsequent analyses is instrumental for research in ecology and evolution. Our aims were to gather reports on the effectiveness of methods commonly used by researchers for the field collection and long‐term storage of blood samples and DNA extracts from wild birds. Personal experiences were collected with an online survey targeted specifically at researchers sampling wild birds. Many researchers experienced problems with blood sample storage but not with DNA extract storage. Storage issues generated problems with obtaining adequate DNA quality and sufficient DNA quantity for the targeted molecular analyses but were not related to season of blood sampling, access to equipment, transporting samples, temperature, and method of blood storage. Final DNA quality and quantity were also not affected by storage time before DNA extraction or the methods used to extract DNA. We discuss practical aspects of field collection and storage and provide some general recommendations, with a list of pros and cons of different preservation methods of avian blood samples and DNA extracts

Swine granulosa cells show typical endothelial cell characteristics

Abstract. Granulosa cells, which belong to the somatic compartment of the ovarian follicle, are actively involved as endocrine cells in follicle growth. Recently, it has been proposed that these cells are not terminally differentiated and possess multipotency. Therefore, we cultured swine granulosa cells in specific endothelial cell culture medium (EBM-2) and phenotypic and functional characteristics of endothelial cells were assessed. The collected data suggest that these endocrine cells can also behave as endothelial cells therefore potentially contributing to follicular angiogenesis, a crucial process in follicle growth and selection

Changes to the gut microbiota of a wild juvenile passerine in a multidimensional urban mosaic

Maraci Ö, Corsini M, Antonatou-Papaioannou A, et al. Changes to the gut microbiota of a wild juvenile passerine in a multidimensional urban mosaic. Scientific Reports. 2022;12(1): 6872.Urbanisation is a major anthropogenic perturbation presenting novel ecological and evolutionary challenges to wild populations. Symbiotic microorganisms residing in the gastrointestinal tracts (gut) of vertebrates have mutual connections with host physiology and respond quickly to environmental alterations. However, the impact of anthropogenic changes and urbanisation on the gut microbiota remains poorly understood, especially in early development. To address this knowledge gap, we characterised the gut microbiota of juvenile great tits (Parus major) reared in artificial nestboxes and in natural cavities in an urban mosaic, employing two distinct frameworks characterising the urban space. Microbial diversity was influenced by cavity type. Alpha diversity was affected by the amount of impervious surface surrounding the breeding location, and positively correlated with tree cover density. Community composition differed between urban and rural sites: these alterations covaried with sound pollution and distance to the city centre. Overall, the microbial communities reflect and are possibly influenced by the heterogeneous environmental modifications that are typical of the urban space. Strikingly, the choice of framework and environmental variables characterising the urban space can influence the outcomes of such ecological studies. Our results open new perspectives to investigate the impact of microbial symbionts on the adaptive capacity of their hosts. © 2022. The Author(s)