Natural selection, evolution, and demography of salmonine populations experiencing intrusion from non-local stock

Many salmonine taxa experience intrusion into their wild, free-living populations from non-local conspecific and heterospecific individuals. Such intrusion arises most commonly as a result of releases from captive breeding programmes for conservation, or to provide a demographic excess that can be exploited commercially or recreationally. Furthermore, the relocation of conspecific individuals from one population to another, the deliberate stocking of sexually compatible foreign taxa into areas outside of their natural range, and domesticated individuals escaping from fish farms provide additional pathways for intrusion. The relative fitness of non-local to local fish, as well as the effects intrusion has on wild populations, is highly dependent on the ecological context that both types of fish experience and the level of adaptation displayed by the introduced fish. In this thesis, I examine how natural selection and, thus, evolution affect the performance of free-living salmonine populations that have experienced intrusion from non-local (captive-bred, translocated, domesticated) stock. Exploring this interplay can help to identify what conditions allow for, and the extent to which, non-local fish successfully breed in a given wild setting, as well as to determine the effects their breeding has on the demography of the recipient wild population. A better understanding of the roles natural selection and evolution have on demography and population viability is crucial for designing better captive breeding programmes and mitigating against the negative effects sexually compatible foreign taxa and fish farm escapees can have when they spawn in the wild. In Chapter 2, I use a molecular pedigree to estimate the lifetime reproductive success of individual Atlantic salmon and demonstrate that captive-bred fish are 64% less fit than their wild-bred conspecifics when both spawn together in the wild. Furthermore, I found evidence of a transgenerational carry-over effect from the hatchery where the wild-spawned offspring of two captive-bred salmon experienced lower survival to adulthood than the offspring of two wild-bred fish. Finally, I used 43 years of population census data to determine that in years where the proportion of spawners that were captive-bred was larger, the productivity of the whole population was reduced. In Chapter 3, I used the molecular pedigree to explore the evolutionary dynamics of female body size at spawning in Atlantic salmon by applying the variance decomposition methods of quantitative genetics. Female (but not male) salmon experienced positive directional selection for the trait but displayed no phenotypic or evolutionary response despite the trait being genetically heritable and, via the Breeder’s Equation, being predicted to evolve towards larger sizes. By utilising a Bayesian regression technique for decomposing the selection gradient into genetic and environmental components, I determined that the female univariate selection gradient used to predict evolution was upwardly biased by one or more unmeasured, but genetically correlated, traits. This highlights the need to measure more than just the focal trait when examining the evolutionary trajectories of populations as management decisions for intruded populations based on biased predictions could result in unforeseen, negative consequences. Chapter 4 is a review of 91 genetically-explicit eco-evolutionary models in fisheries science, with a particular focus on the genetic architecture employed in the models. With relevance to my thesis, only 15 studies (16.5%) examined captive-wild interactions. 14 of these studies were parameterised for or motivated by the effects of captive-bred releases into wild salmonine populations. Five of these modelled trait inheritance through quantitative genetic architectures, nine used explicit Mendelian models of inheritance, and one study allowed for the independent inheritance of both a quantitative trait and a biallelic locus. Together, the results from Chapters 3 and 4 informed the design of my own genetically-explicit eco-evolutionary model in Chapter 5. In Chapter 5, the aforementioned genetically-explicit eco-evolutionary model was used to explore how soft and hard selection interacted to affect evolution and demography in a salmonine population that had experienced intrusion from non-local stock. Non-local alleles were purged faster from the population when soft selection was stronger. Soft selection also indirectly influenced the strength of hard selection. By limiting the number of maladapted individuals that could breed, soft selection reduced introgression from maladapted alleles into the wild population. This caused a reduction in the number of fish displaying maladaptive phenotypes that would be selected against by hard selection, thus, weakening the strength of hard selection. Furthermore, the weakening of hard selection buffered against the demographic declines associated with this form of natural selection. The results of this chapter demonstrate how unexpected evolutionary dynamics can emerge in populations and how variation in the ecological context (in this case, the form and strength of both soft and hard selection) affects evolution and demography. This thesis emphasises how variation in natural selection and the extent of intrusion/introgression impacts the evolutionary dynamics observed in salmonine populations that experience intrusion/introgression from non-local fish. Chapter 2 adds to the ever-growing list of studies describing reduced fitness for captive- relative to wild-bred fish while also providing a known example of how increasing numbers of captive-bred fish lead to a concomitant reduction in population productivity. The genetically-explicit eco-evolutionary model resulting from work done for Chapters 3, 4, and 5 stresses how the form and strength of natural selection can vary depending not just on prevailing ecological conditions but also on the genotypic/phenotypic composition of both the wild population and introduced individuals. A greater understanding of how evolutionary dynamics emerge and what conditions lead to a particular set of dynamics is critical in mitigating against the negative impacts arising from the deliberate or accidental release of non-local individuals into wild populations

The prevalence of severe sepsis or septic shock in an Irish emergency department

Severe sepsis and septic shock are among the leading causes of death globally. Despite the central role the emergency department (ED) plays in the early identification of patients presenting to hospital with sepsis, the prevalence of severe sepsis and septic shock in the Irish ED setting has not been described. The primary aim of this study was to measure the prevalence of severe sepsis or septic shock in an Irish adult ED setting. The clinical records of patients presenting to the ED over a four-week period were retrospectively reviewed to determine if they met the current Health Service Executive (HSE) criteria for severe sepsis or septic shock. Overall, 3,585 adult patients attended the ED during the study period, with 42 patients meeting the criteria for severe sepsis or septic shock. The ED prevalence of severe sepsis or septic shock was 11.7 patients (95% CI 8.1 – 15.4%) per 1000 ED attendances

Knowledge, attitudes and beliefs of parents regarding fever in children: a Danish interview study

Aim: Fever and febrile illness are some of the most common conditions managed by parents. The aim of this study was to examine the knowledge, attitudes and beliefs of parents around fever in children under five years of age. Methods: Between July and August 2014, a convenience sample of parents was invited to participate in this study in Copenhagen, Denmark. Results were analysed thematically using a constant comparison method. Results: Twenty-one parents participated in the study. Five themes emerged from the data: parental concern, help-seeking behaviour, parental knowledge, parent fever management practices and initiatives. Parents used a range of information sources to obtain their knowledge on management of fever; however, due to issues of trust with these sources, reassurance was often sought from healthcare practitioners. There was a desire amongst most parents for initiatives to be introduced which provide general information on how to manage fever in children. Conclusion: Parents were very concerned when their child was febrile and instigated practices obtained from accessible information sources. This study has identified a need for specific and reliable information initiatives to be introduced as a means of reducing parental concern and ensuring evidence-based strategies for managing a child with fever

Escalating the conflict? Intersex genetic correlations influence adaptation to environmental change in facultatively migratory populations

Males and females are often subject to different and even opposing selection pressures. When a given trait has a shared genetic basis between the sexes, sexual conflict (antagonism) can arise. This can result in significant individual-level fitness consequences that might also affect population performance, whilst anthropogenic environmental change can further exacerbate maladaptation in one or both sexes driven by sexual antagonism. Here, we develop a genetically explicit eco-evolutionary model using an agent-based framework to explore how a population of a facultatively migratory fish species (brown trout Salmo trutta) adapts to environmental change across a range of intersex genetic correlations for migration propensity, which influence the magnitude of sexual conflict. Our modelled focal trait represents a condition threshold governing whether individuals adopt a resident or anadromous (sea migration) tactic. Anadromy affords potential size-mediated reproductive advantages to both males and females due to improved feeding opportunities at sea, but these can be undermined by high background marine mortality and survival/growth costs imposed by marine parasites (sea lice). We show that migration tactic frequency for a given set of environmental conditions is strongly influenced by the intersex genetic correlation, such that one sex can be dragged off its optimum more than the other. When this occurred in females in our model, population productivity was substantially reduced, but eco-evolutionary outcomes were altered by allowing for sneaking behaviour in males. We discuss real-world implications of our work given that anadromous salmonids are regularly challenged by sea lice infestations, which might act synergistically with other stressors such as climate change or fishing that impact marine performance, driving populations towards residency and potentially reduced resilience.Peer reviewe

Establishing the research priorities of paediatric emergency medicine clinicians in the UK and Ireland

Objective: Paediatric Emergency Research in the UK and Ireland (PERUKI) is a collaborative clinical studies group established in August 2012. It consists of a network of 43 centres from England, Ireland, Northern Ireland, Scotland and Wales, and aims to improve the emergency care of children through the performance of robust collaborative multicentre research within emergency departments. A study was conducted regarding the research priorities of PERUKI, to establish the research agenda for paediatric emergency medicine in the UK and Ireland. Methods: A two-stage modified Delphi survey was conducted of PERUKI members via an online survey platform. Stage 1 allowed each member to submit up to 12 individual questions that they identified as priorities for future research. In stage 2, the shortlisted questions were each rated on a seven-point Likert scale of relative importance. Participants: Members of PERUKI, including clinical specialists, academics, trainees and research nurses. Results: Stage 1 surveys were submitted by 46/91 PERUKI members (51%). A total of 249 research questions were generated and, following the removal of duplicate questions and shortlisting, 60 questions were carried forward for stage 2 ranking. Stage 2 survey responses were submitted by 58/95 members (61%). For the 60 research questions that were rated, the mean score of 'relative degree of importance' was 4.70 (range 3.36-5.62, SD 0.55). After ranking, the top 10 research priorities included questions on biomarkers for serious bacterial illness, major trauma, intravenous bronchodilators for asthma and decision rules for fever with petechiae, head injury and atraumatic limp. Conclusions: Research priorities of PERUKI members have been identified. By sharing these results with clinicians, academics and funding bodies, future research efforts can be focused to the areas of greatest need

The Penicillin for the Emergency Department Outpatient treatment of CELLulitis (PEDOCELL) trial: update to the study protocol and detailed statistical analysis plan (SAP)

Background: Cellulitis is a painful, potentially serious, infectious process of the dermal and subdermal tissues and represents a significant disease burden. The statistical analysis plan (SAP) for the Penicillin for the Emergency Department Outpatient treatment of CELLulitis (PEDOCELL) trial is described here. The PEDOCELL trial is a multicentre, randomised, parallel-arm, double-blinded, non-inferiority clinical trial comparing the efficacy of flucloxacillin (monotherapy) with combination flucloxacillin/phenoxymethylpenicillin (dual therapy) for the outpatient treatment of cellulitis in the emergency department (ED) setting. To prevent outcome reporting bias, selective reporting and data-driven results, the a priori-defined, detailed SAP is presented here. Methods/design: Patients will be randomised to either orally administered flucloxacillin 500 mg four times daily and placebo or orally administered 500 mg of flucloxacillin four times daily and phenoxymethylpenicillin 500 mg four times daily. The trial consists of a 7-day intervention period and a 2-week follow-up period. Study measurements will be taken at four specific time points: at patient enrolment, day 2-3 after enrolment and commencing treatment (early clinical response (ECR) visit), day 8-10 after enrolment (end-of-treatment (EOT) visit) and day 14-21 after enrolment (test-of-cure (TOC) visit). The primary outcome measure is investigator-determined clinical response measured at the TOC visit. The secondary outcomes are as follows: lesion size at ECR, clinical treatment failure at each follow-up visit, adherence and persistence of trial patients with orally administered antibiotic therapy at EOT, health-related quality of life (HRQoL) and pharmacoeconomic assessments. The plan for the presentation and comparison of baseline characteristics and outcomes is described in this paper. Discussion: This trial aims to establish the non-inferiority of orally administered flucloxacillin monotherapy with orally administered flucloxacillin/phenoxymethylpenicillin dual therapy for the ED-directed outpatient treatment of cellulitis. In doing so, this trial will bridge a knowledge gap in this understudied and common condition and will be relevant to clinicians across several different disciplines. The SAP for the PEDOCELL trial was developed a priori in order to minimise analysis bias

Economic (gross cost) analysis of systematically implementing a programme of advance care planning in three Irish nursing homes.

Background: Although advance care planning (ACP) and the use of advanced care directives (ACD) and end-of-life care plans are associated with a reduction in inappropriate hospitalisation, there is little evidence supporting the economic benefits of such programmes. We assessed the economic impact (gross savings) of the Let Me Decide (LMD) ACP programme in Ireland, specifically the impact on hospitalisations, bed days and location of resident deaths, before and after systematic implementation of the LMD-ACP combined with a palliative care education programme. Methods: The LMD-ACP was introduced into three long-term care (LTC) facilities in Southern Ireland and outcomes were compared pre and post implementation. In addition, 90 staff were trained in a palliative care educational programme. Economic analysis including probabilistic sensitivity analysis was performed. Results: The uptake of an ACD or end-of-life care post-implementation rose from 25 to 76 %. Post implementation, there were statistically significant decreases in hospitalisation rates from baseline (hospitalisation incidents declined from 27.8 to 14.6 %, z = 3.96, p < 0.001; inpatient hospital days reduced from 0.54 to 0.36 %, z = 8.85, p < 0.001). The percentage of hospital deaths also decreased from 22.9 to 8.4 %, z = 3.22, p = 0.001. However, length of stay (LOS) increased marginally (7–9 days). Economic analysis suggested a cost-reduction related to reduced hospitalisations ranging between €10 and €17.8 million/annum and reduction in ambulance transfers, estimated at €0.4 million/annum if these results were extrapolated nationally. When unit costs and LOS estimates were varied in scenario analyses, the expected cost reduction owing to reduced hospitalisations, ranged from €17.7 to €42.4 million nationally. Conclusions: Implementation of the LMD-ACP (ACD/end-of-life care plans combined with palliative care education) programme resulted in reduced rates of hospitalisation. Despite an increase in LOS, likely reflecting more complex care needs of admitted residents, gross costs were reduced and scenario analysis projected large annual savings if these results were extrapolated to the wider LTC population in Ireland

Study protocol for evaluating the implementation and effectiveness of an emergency department longitudinal patient monitoring system using a mixed-methods approach

Background: Early detection of patient deterioration is a key element of patient safety as it allows timely clinical intervention and potential rescue, thus reducing the risks of serious patient safety incidents. Longitudinal patient monitoring systems have been widely recommended for use to detect clinical deterioration. However, there is conflicting evidence on whether they improve patient outcomes. This may in part be related to variation in the rigour with which they are implemented and evaluated. This study aims to evaluate the implementation and effectiveness of a longitudinal patient monitoring system designed for adult patients in the unique environment of the Emergency Department (ED). Methods: A novel participatory action research (PAR) approach is taken where socio-technical systems (STS) theory and analysis informs the implementation through the improvement methodology of ‘Plan Do Study Act’ (PDSA) cycles. We hypothesise that conducting an STS analysis of the ED before beginning the PDSA cycles will provide for a much richer understanding of the current situation and possible challenges to implementing the ED-specific longitudinal patient monitoring system. This methodology will enable both a process and an outcome evaluation of implementing the ED-specific longitudinal patient monitoring system. Process evaluations can help distinguish between interventions that have inherent faults and those that are badly executed. Discussion: Over 1.2 million patients attend EDs annually in Ireland; the successful implementation of an ED-specific longitudinal patient monitoring system has the potential to affect the care of a significant number of such patients. To the best of our knowledge, this is the first study combining PAR, STS and multiple PDSA cycles to evaluate the implementation of an ED-specific longitudinal patient monitoring system and to determine (through process and outcome evaluation) whether this system can significantly improve patient outcomes by early detection and appropriate intervention for patients at risk of clinical deterioration

Genetic stock identification reveals greater use of an oceanic feeding ground around the Faroe Islands by multi-sea winter Atlantic salmon, with variation in use across reporting groups

While it is known that the oceans around the Faroe Islands support an Atlantic salmon (Salmo salar) feeding ground, the relative use of this resource by different age classes and populations remains largely unexplored. Using genetic stock identification and run-reconstruction modelling, we observed a consistent pattern whereby the proportion of multi-sea winter salmon (MSW-fish that have spent multiple winters at sea) for a reporting group was substantially greater around the Faroes than the MSW proportion among that group's corresponding pre-fisheries abundance. Surprisingly, MSW fish from Ireland and the United Kingdom were as likely to occur around the Faroes as were MSW fish from more north-eastern regions. While 1SW salmon (single sea-winter fish) from Ireland and the United Kingdom as well as Southern Norway occurred in similar proportions around the Faroes, 1SW fish from the north-eastern regions were virtually absent. Our results indicate that the oceans around the Faroes host a predominantly MSW feeding ground and use of this resource varies across age classes and reporting groups. Furthermore, these results suggest that MSW fish from some reporting groups preferentially migrate to the Faroes. Variation in spatial resource use may help buffer salmon populations against localized negative changes in marine conditions via portfolio effects.Peer reviewe