scholarly journals Temporal Dynamics of the Gut Bacteriome and Mycobiome in the Weanling Pig

2020 ◽  
Vol 8 (6) ◽  
pp. 868
Author(s):  
Ann M. Arfken ◽  
Juli Foster Frey ◽  
Katie Lynn Summers

Weaning is a period of environmental changes and stress that results in significant alterations to the piglet gut microbiome and is associated with a predisposition to disease, making potential interventions of interest to the swine industry. In other animals, interactions between the bacteriome and mycobiome can result in altered nutrient absorption and susceptibility to disease, but these interactions remain poorly understood in pigs. Recently, we assessed the colonization dynamics of fungi and bacteria in the gastrointestinal tract of piglets at a single time point post-weaning (day 35) and inferred interactions were found between fungal and bacterial members of the porcine gut ecosystem. In this study, we performed a longitudinal assessment of the fecal bacteriome and mycobiome of piglets from birth through the weaning transition. Piglet feces in this study showed a dramatic shift over time in the bacterial and fungal communities, as well as an increase in network connectivity between the two kingdoms. The piglet fecal bacteriome showed a relatively stable and predictable pattern of development from Bacteroidaceae to Prevotellaceae, as seen in other studies, while the mycobiome demonstrated a loss in diversity over time with a post-weaning population dominated by Saccharomycetaceae. The mycobiome demonstrated a more transient community that is likely driven by factors such as diet or environmental exposure rather than an organized pattern of colonization and succession evidenced by fecal sample taxonomic clustering with nursey feed samples post-weaning. Due to the potential tractability of the community, the mycobiome may be a viable candidate for potential microbial interventions that will alter piglet health and growth during the weaning transition.

2021 ◽  
Vol 11 ◽  
Author(s):  
Janneke Schreuder ◽  
Francisca C. Velkers ◽  
Alex Bossers ◽  
Ruth J. Bouwstra ◽  
Willem F. de Boer ◽  
...  

Associations between animal health and performance, and the host’s microbiota have been recently established. In poultry, changes in the intestinal microbiota have been linked to housing conditions and host development, but how the intestinal microbiota respond to environmental changes under farm conditions is less well understood. To gain insight into the microbial responses following a change in the host’s immediate environment, we monitored four indoor flocks of adult laying chickens three times over 16 weeks, during which two flocks were given access to an outdoor range, and two were kept indoors. To assess changes in the chickens’ microbiota over time, we collected cloacal swabs of 10 hens per flock and performed 16S rRNA gene amplicon sequencing. The poultry house (i.e., the stable in which flocks were housed) and sampling time explained 9.2 and 4.4% of the variation in the microbial community composition of the flocks, respectively. Remarkably, access to an outdoor range had no detectable effect on microbial community composition, the variability of microbiota among chickens of the same flock, or microbiota richness, but the microbiota of outdoor flocks became more even over time. Fluctuations in the composition of the microbiota over time within each poultry house were mainly driven by turnover in rare, rather than dominant, taxa and were unique for each flock. We identified 16 amplicon sequence variants that were differentially abundant over time between indoor and outdoor housed chickens, however none were consistently higher or lower across all chickens of one housing type over time. Our study shows that cloacal microbiota community composition in adult layers is stable following a sudden change in environment, and that temporal fluctuations are unique to each flock. By exploring microbiota of adult poultry flocks within commercial settings, our study sheds light on how the chickens’ immediate environment affects the microbiota composition.


2021 ◽  
Vol 9 ◽  
Author(s):  
Elizabeth Barthelemy ◽  
Claire Fortunel ◽  
Maxime Jaunatre ◽  
François Munoz

Past environmental changes have shaped the evolutionary and ecological diversity of extant organisms. Specifically, climatic fluctuations have made environmental conditions alternatively common or rare over time. Accordingly, most taxa have undergone restriction of their distribution to local refugia during habitat contraction, from which they could expand when suitable habitat became more common. Assessing how past restrictions in refugia have shaped species distributions and genetic diversity has motivated much research in evolutionary biology and biogeography. But there is still lack of clear synthesis on whether and how the taxonomic, functional and phylogenetic composition of extant multispecies assemblages retains the imprint of past restriction in refugia. We devised an original eco-evolutionary model to investigate the temporal dynamics of a regional species pool inhabiting a given habitat today, and which have experienced habitat reduction in the past. The model includes three components: (i) a demographic component driving stochastic changes in population sizes and extinctions due to habitat availability, (ii) a mutation and speciation component representing how divergent genotypes emerge and define new species over time, and (iii) a trait evolution component representing how trait values have changed across descendants over time. We used this model to simulate dynamics of multispecies assemblages that occupied a restricted refugia in the past and could expand their distribution subsequently. We characterized the past restriction in refugia in terms of two parameters representing the ending time of past refugia, and the extent of habitat restriction in the refugia. We characterized extant patterns of taxonomic, functional and phylogenetic diversity depending on these parameters. We found that extant relative abundances reflect the lasting influence of more recent refugia on demographic dynamics, while phylogenetic composition reflects the influence of more ancient habitat change. Extant functional diversity depends on the interplay between diversification dynamics and trait evolution, offering new options to jointly infer current trait adaptation and past trait evolution dynamics.


Author(s):  
Thomas L Rodebaugh ◽  
Madelyn R Frumkin ◽  
Angela M Reiersen ◽  
Eric J Lenze ◽  
Michael S Avidan ◽  
...  

Abstract Background The symptoms of COVID-19 appear to be heterogenous, and the typical course of these symptoms is unknown. Our objectives were to characterize the common trajectories of COVID-19 symptoms and assess how symptom course predicts other symptom changes as well as clinical deterioration. Methods 162 participants with acute COVID-19 responded to surveys up to 31 times for up to 17 days. Several statistical methods were used to characterize the temporal dynamics of these symptoms. Because nine participants showed clinical deterioration, we explored whether these participants showed any differences in symptom profiles. Results Trajectories varied greatly between individuals, with many having persistently severe symptoms or developing new symptoms several days after being diagnosed. A typical trajectory was for a symptom to improve at a decremental rate, with most symptoms still persisting to some degree at the end of the reporting period. The pattern of symptoms over time suggested a fluctuating course for many patients. Participants who showed clinical deterioration were more likely to present with higher reports of severity of cough and diarrhea. Conclusion The course of symptoms during the initial weeks of COVID-19 is highly heterogeneous and is neither predictable nor easily characterized using typical survey methods. This has implications for clinical care and early-treatment clinical trials. Additional research is needed to determine whether the decelerating improvement pattern seen in our data is related to the phenomenon of patients reporting long-term symptoms, and whether higher symptoms of diarrhea in early illness presages deterioration.


Author(s):  
Mari Huhtala ◽  
Muel Kaptein ◽  
Joona Muotka ◽  
Taru Feldt

AbstractThe aim of this longitudinal study was to investigate the temporal dynamics of ethical organisational culture and how it associates with well-being at work when potential changes in ethical culture are measured over an extended period of 6 years. We used a person-centred study design, which allowed us to detect both typical and atypical patterns of ethical culture stability as well as change among a sample of leaders. Based on latent profile analysis and hierarchical linear modelling we found longitudinal, concurrent relations and cumulative gain and loss cycles between different ethical culture patterns and leaders’ well-being. Leaders in the strongest ethical culture pattern experienced the highest level of work engagement and a decreasing level of ethical dilemmas and stress. Leaders who gave the lowest ratings on ethical culture which also decreased over time reported the highest level of ethical dilemmas, stress, and burnout. They also showed a continuous increase in these negative outcomes over time. Thus, ethical culture has significant cumulative effects on well-being, and these longitudinal effects can be both negative and positive, depending on the experienced strength of the culture’s ethicality.


2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S325-S326
Author(s):  
Lacy Simons ◽  
Ramon Lorenzo-Redondo ◽  
Hannah Nam ◽  
Scott C Roberts ◽  
Michael G Ison ◽  
...  

Abstract Background The rapid spread of SARS-CoV-2, the causative agent of Coronavirus disease 2019 (COVID-19), has been accompanied by the emergence of viral mutations, some of which may have distinct virological and clinical consequences. While whole genome sequencing efforts have worked to map this viral diversity at the population level, little is known about how SARS-CoV-2 may diversify within a host over time. This is particularly important for understanding the emergence of viral resistance to therapeutic interventions and immune pressure. The goal of this study was to assess the change in viral load and viral genome sequence within patients over time and determine if these changes correlate with clinical and/or demographic parameters. Methods Hospitalized patients admitted to Northwestern Memorial Hospital with a positive SARS-CoV-2 test were enrolled in a longitudinal study for the serial collection of nasopharyngeal specimens. Swabs were administered to patients by hospital staff every 4 ± 1 days for up to 32 days or until the patients were discharged. RNA was extracted from each specimen and viral loads were calculated by quantitative reverse transcriptase PCR (qRT-PCR). Specimens with qRT-PCR cycle threshold values less than or equal to 30 were subject to whole viral genome sequencing by reverse transcription, multiplex PCR, and deep sequencing. Variant populations sizes were estimated and subject to phylogenetic analysis relative to publicly available SARS-CoV-2 sequences. Sequence and viral load data were subsequently correlated to available demographic and clinical data. Results 60 patients were enrolled from March 26th to June 20th, 2020. We observed an overall decrease in nasopharyngeal viral load over time across all patients. However, the temporal dynamics of viral load differed on a patient-by-patient basis. Several mutations were also observed to have emerged within patients over time. Distribution of SARS-CoV-2 viral loads in serially collected nasopharyngeal swabs in hospitalized adults as determined by qRT-PCR. Samples were collected every 4 ± 1 days (T#1–8) and viral load is displayed by log(copy number). Conclusion These data indicate that SARS-CoV-2 viral loads in the nasopharynx decrease over time and that the virus can accumulate mutations during replication within individual patients. Future studies will examine if some of these mutations may provide fitness advantages in the presence of therapeutic and/or immune selective pressures. Disclosures Michael G. Ison, MD MS, AlloVir (Consultant)


2018 ◽  
Vol 75 (7) ◽  
pp. 2463-2475 ◽  
Author(s):  
Romain Frelat ◽  
Alessandro Orio ◽  
Michele Casini ◽  
Andreas Lehmann ◽  
Bastien Mérigot ◽  
...  

Abstract Fisheries and marine ecosystem-based management requires a holistic understanding of the dynamics of fish communities and their responses to changes in environmental conditions. Environmental conditions can simultaneously shape the spatial distribution and the temporal dynamics of a population, which together can trigger changes in the functional structure of communities. Here, we developed a comprehensive framework based on complementary multivariate statistical methodologies to simultaneously investigate the effects of environmental conditions on the spatial, temporal and functional dynamics of species assemblages. The framework is tested using survey data collected during more than 4000 fisheries hauls over the Baltic Sea between 2001 and 2016. The approach revealed the Baltic fish community to be structured into three sub-assemblages along a strong and temporally stable salinity gradient decreasing from West to the East. Additionally, we highlight a mismatch between species and functional richness associated with a lower functional redundancy in the Baltic Proper compared with other sub-areas, suggesting an ecosystem more susceptible to external pressures. Based on a large dataset of community data analysed in an innovative and comprehensive way, we could disentangle the effects of environmental changes on the structure of biotic communities—key information for the management and conservation of ecosystems.


2015 ◽  
Vol 9 (9) ◽  
pp. e0004090
Author(s):  
Frederik Van den Broeck ◽  
Gregory E. Maes ◽  
Maarten H. D. Larmuseau ◽  
David Rollinson ◽  
Ibrahima Sy ◽  
...  

2021 ◽  
Author(s):  
Natasa Ravbar ◽  
Cyril Mayaud ◽  
Matej Blatnik ◽  
Metka Petrič

<p>Under special meteorological and hydrological circumstances, shallow karst areas and karst poljes may experience surface water overflow. As a result, surface- groundwater interaction occurs usually creating intermittent lakes. Although human settlements and activities have traditionally adapted to these natural conditions, extensive temporary floods are classified among the most common natural disasters in karst. On the other hand, intermittent lakes are considered as natural reservoirs of excess recharge and good flood regulators in the lower parts of river basins. Due to specific ecohydrological processes and environmental conditions, these areas host unique wetland ecosystems with high levels of biodiversity and provide various ecosystem services, such as ecological productivity, photosynthesis and carbon storage. Given the dynamic nature of hydrological processes in karst aquifers, a distinctive feature of the phenomena described is its high variability of occurrence and duration. Therefore, the identification, characterization as well as the determination of the spatial dimension of flood levels is a challenging task. Focusing on the Slovenian karst, a literature review and analysis of topographical and hydrological data of the selected study areas was conducted. The hydrological analyses were based on long-term monitoring data from Slovenian Environmental Agency and partly on the authors' own database of field measurements and knowledge of the areas concerned. Consequently, the conceptual framework and the key criterion for the determination and recording of areas subject to temporary flooding were developed. A systematic survey reveals the significance of the extent, duration and frequency of flooding. Evaluation results are useful to designers of various water policies and management mechanisms for flood mitigation and protection of special habitats. Observing trends in the spatial and temporal dynamics of flood levels is also valuable for understanding how and to what extent karst aquifers are vulnerable to environmental changes. Finally, the analyses also enable prediction of the effects of these changes on other parts of the environment (e.g., hydrophilic habitats).</p>


2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi162-vi162
Author(s):  
Melissa Gardner ◽  
Giuliana Zarrella ◽  
Jorg Dietrich ◽  
Michael Parsons

Abstract INTRODUCTION Estimates of subjective cognitive function (SCF) generally show minimal correlation with objective measures of neurocognitive function (NCF). Our group recently validated a new metric of SCF in neuro-oncology patients, creating the Cognitive Index of the Functional Assessment of Cancer Therapy-Brain (FACT-Br-CI). This study examines whether brain tumor (BT) patients evaluated on more than one occasion show improved relationship between SCF and NCF. We hypothesized that change scores in SCF and NCF across evaluation would be more highly correlated than SCF and NCF at either timepoint. METHODS A retrospective study of BT patients who completed two neuropsychological evaluations (baseline, follow-up) was conducted. NCF was measured by the clinical trial battery composite (CTBC), a mean of 6 commonly used neuropsychological test scores. SCF was measured by the FACT-Br-CI. Mood/Anxiety were measured by the Beck scales (BAI/BDI-II). Change over time on each metric was evaluated with paired t-test. Correlational analyses evaluated relationships between NCF, SCF, and mood within and between time points. RESULTS Twenty-nine patients (16 female; mean age=54.6y; mean education=15.5y) completed all CTBC measures and FACT-Br-CI, 28 of whom completed and BDI and/or BAI. On group analyses, there were no significant differences between baseline and follow-up on CTBC (t=-.53;p=ns) or FACT-Br-CI (t=-.98;p=ns). Correlations between CTBC and FACT-Br-CI were nonsignificant at baseline (r=.24;p=ns), but significant at follow-up (r=.56;p=0.002). Change scores over time were unrelated (r=-.104;p=ns). Similar to previous studies, the FACT-BR-CI correlated with the BDI-II at baseline (r=-.38;p=0.04) and follow-up (r=-.59;p< 0.001) and with the BAI at follow-up (r=-.44;p=0.02). CONCLUSION In this small group of brain tumor patients seen for repeated neuropsychological evaluations, we found that agreement between SCF and NCF was much higher on their second than initial evaluation. These findings suggest that patients may develop enhanced awareness of their cognitive function from an initial evaluation that persists over time.


2022 ◽  
pp. 002076402110701
Author(s):  
Rajesh Sagar ◽  
Mahadev Singh Sen ◽  
Nand Kumar ◽  
Nishtha Chawla

Objectives: To assess and compare the changes in disability scores associated with Bipolar Depression (BD) and Unipolar Depression (UD) over 1 year. Methods: A longitudinal study was taken up in adults diagnosed with unipolar or bipolar depressive disorder with current depressive episode. Diagnosis was made according to Schedule for Clinical Assessment in Neuropsychiatry. Severity scoring was done using Hamilton’s Depression (HAM-D) rating scale and Hamilton’s Anxiety (HAM-A) rating scale. Disability was assessed using Indian Disability Evaluation and Assessment Scale (IDEAS) and London handicap Scale (LHS) at baseline, 6 and 12 months. Results: Sixty participants were recruited (42 UD and 18 BD). No significant differences were seen in socio-demographic parameters, except higher education levels and males being overrepresented in UD. Significant differences at baseline were seen in HAM-D ( p = .001) and HAM-A ( p = .003) scores. The extent of disability was seen to correlate with severity of illness only in case of BD at baseline. No significant differences were seen in the IDEAS scores at baseline. IDEAS score improved at each follow-up assessment ( p < .001). LHS showed significant improvement over time in UD ( p < .001), but not BD ( p = .076). Percentage individuals meeting cut-off for benchmark disability (>40%) were comparable at baseline but were significantly more in the BD at 12-months ( p = .049). Conclusion and implications: Disability in psychiatry occurs equally amongst unipolar and bipolar depressive disorders and tends to improve over time, although the level of improvement may differ. It may not always correspond to severity of illness. These factors should be considered while certifying disability.


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