360 research outputs found
Leg disorders in broiler chickens : prevalence, risk factors and prevention
Broiler (meat) chickens have been subjected to intense genetic selection. In the past 50 years, broiler growth rates have increased
by over 300% (from 25 g per day to 100 g per day). There is growing societal concern that many broiler chickens have impaired
locomotion or are even unable to walk. Here we present the results of a comprehensive survey of commercial flocks which
quantifies the risk factors for poor locomotion in broiler chickens.We assessed the walking ability of 51,000 birds, representing 4.8
million birds within 176 flocks.We also obtained information on approximately 150 different management factors associated with
each flock. At a mean age of 40 days, over 27.6% of birds in our study showed poor locomotion and 3.3% were almost unable to
walk. The high prevalence of poor locomotion occurred despite culling policies designed to remove severely lame birds from
flocks. We show that the primary risk factors associated with impaired locomotion and poor leg health are those specifically
associated with rate of growth. Factors significantly associated with high gait score included the age of the bird (older birds), visit
(second visit to same flock), bird genotype, not feeding whole wheat, a shorter dark period during the day, higher stocking density
at the time of assessment, no use of antibiotic, and the use of intact feed pellets. The welfare implications are profound. Worldwide
approximately 261010 broilers are reared within similar husbandry systems.We identify a range of management factors that could
be altered to reduce leg health problems, but implementation of these changes would be likely to reduce growth rate and
production. A debate on the sustainability of current practice in the production of this important food source is required
Compensatory density feedback of Oncomelania hupensis populations in two different environmental settings in China
BACKGROUND: The most recent strategy for schistosomiasis control in the People's Republic of China aims to reduce the likelihood of environmental contamination of schistosome eggs. Despite considerable progress, it is believed that achievements would be further consolidated with additional intermediate host snail control measures. We provide an empirical framework for discerning the relative contribution of intrinsic effects (density feedback) from other extrinsic drivers of snail population dynamics.
METHODS: We set up experiments in two study locations to collect reproduction data of Oncomelania hupensis, the intermediate host snail of Schistosoma japonicum. We applied a set of four population dynamic models that have been widely used to study phenomenological time-series data to examine the properties of demographic density feedback patterns from abundance data. We also contrasted the obtained results with the component feedback of density on survival rate to determine whether adult survival was the principal driver of the demographic feedback observed.
RESULTS: Demographic density feedback models (Ricker- and Gompertz-logistic) accounted for <99% of Akaike's information criterion model weight, with the Gompertz ranking highest in all O. hupensis population groups. We found some evidence for stronger compensatory feedback in the O. hupensis population from Sichuan compared to a Jiangsu population. Survival rates revealed strong component feedback, but the log-linear relationships (i.e. Gompertz) had less support in the demographic feedback analysis.
CONCLUSIONS: Our findings indicate that integrated schistosomiasis control measures must continue to reduce parasite abundance further because intermediate host snail populations tend to grow exponentially at low densities, especially O. hupensis populations in mountainous regions. We conclude that density feedback in adult survival is the principal component contribution to the demographic phenomenon observed in the population fitness (r)-abundance relationship
Polymicrobial Nature of Chronic Diabetic Foot Ulcer Biofilm Infections Determined Using Bacterial Tag Encoded FLX Amplicon Pyrosequencing (bTEFAP)
Diabetic extremity ulcers are associated with chronic infections. Such ulcer infections are too often followed by amputation because there is little or no understanding of the ecology of such infections or how to control or eliminate this type of chronic infection. A primary impediment to the healing of chronic wounds is biofilm phenotype infections. Diabetic foot ulcers are the most common, disabling, and costly complications of diabetes. Here we seek to derive a better understanding of the polymicrobial nature of chronic diabetic extremity ulcer infections. spp. and against difficult to culture bacteria such as anaerobes. While PCR methods also have bias, further work is now needed in comparing traditional culture results to high-resolution molecular diagnostic methods such as bTEFAP
Ecological Niche Dimensionality and the Evolutionary Diversification of Stick Insects
The degree of phenotypic divergence and reproductive isolation between taxon pairs can vary quantitatively, and often increases as evolutionary divergence proceeds through various stages, from polymorphism to population differentiation, ecotype and race formation, speciation, and post-speciational divergence. Although divergent natural selection promotes divergence, it does not always result in strong differentiation. For example, divergent selection can fail to complete speciation, and distinct species pairs sometimes collapse (‘speciation in reverse’). Widely-discussed explanations for this variability concern genetic architecture, and the geographic arrangement of populations. A less-explored possibility is that the degree of phenotypic and reproductive divergence between taxon pairs is positively related to the number of ecological niche dimensions (i.e., traits) subject to divergent selection. Some data supporting this idea stem from laboratory experimental evolution studies using Drosophila, but tests from nature are lacking. Here we report results from manipulative field experiments in natural populations of herbivorous Timema stick insects that are consistent with this ‘niche dimensionality’ hypothesis. In such insects, divergent selection between host plants might occur for cryptic colouration (camouflage to evade visual predation), physiology (to detoxify plant chemicals), or both of these niche dimensions. We show that divergent selection on the single niche dimension of cryptic colouration can result in ecotype formation and intermediate levels of phenotypic and reproductive divergence between populations feeding on different hosts. However, greater divergence between a species pair involved divergent selection on both niche dimensions. Although further replication of the trends reported here is required, the results suggest that dimensionality of selection may complement genetic and geographic explanations for the degree of diversification in nature
Evaluation of a Medical and Mental Health Unit compared with standard care for older people whose emergency admission to an acute general hospital is complicated by concurrent 'confusion': a controlled clinical trial. Acronym: TEAM: Trial of an Elderly Acute care Medical and mental health unit
Background: Patients with delirium and dementia admitted to general hospitals have poor outcomes, and their carers report poor experiences. We developed an acute geriatric medical ward into a specialist Medical and Mental Health Unit over an eighteen month period. Additional specialist mental health staff were employed, other staff were trained in the ‘person-centred’ dementia care approach, a programme of meaningful activity was devised, the environment adapted to the needs of people with cognitive impairment, and attention given to communication with family carers. We hypothesise that patients managed on this ward will have better outcomes than those receiving standard care, and that such care will be cost-effective.
Methods/design: We will perform a controlled clinical trial comparing in-patient management on a specialist Medical and Mental Health Unit with standard care. Study participants are patients over the age of 65, admitted as an emergency to a single general hospital, and identified on the Acute Medical Admissions Unit as being ‘confused’. Sample size is 300 per group. The evaluation design has been adapted to accommodate pressures on bed management and patient flows. If beds are available on the specialist Unit, the clinical service allocates patients at random between the Unit and standard care on general or geriatric medical wards. Once admitted, randomised patients and their carers are invited to take part in a follow up study, and baseline data are collected. Quality of care and patient experience are assessed in a non-participant observer study. Outcomes are ascertained at a follow up home visit 90 days after randomisation, by a researcher blind to allocation. The primary outcome is days spent at home (for those admitted from home), or days spent in the same care home (if admitted from a care home). Secondary outcomes include mortality, institutionalisation, resource use, and scaled outcome measures, including quality of life, cognitive function, disability, behavioural and psychological symptoms, carer strain and carer satisfaction with hospital care. Analyses will comprise comparisons of process, outcomes and costs between the specialist unit and standard care treatment groups.
Trial Registration number: ClinicalTrials.gov: NCT0113614
Особенности развития малого предпринимательства в Украине
В этой работе рассмотрена эволюция предпринимательства Украины на всех этапах ее общественной жизни, в том числе в период экономического кризиса в годы становления независимости. Отражены основные параметры отнесения предприятий к субъектам малого предпринимательства и их роль в развитии экономики государств.У цій роботі розглянута еволюція підприємництва України на всіх етапах її суспільного життя, зокрема в період економічної кризи в роки становлення незалежності. Відображені основні параметри віднесення підприємств до суб'єктів малого підприємництва і їх роль в розвитку економіки держав
Developing a Collaboration with the Houston Independent School District: Testing the Generalizability of a Partnership Model
Moving evidence-based practices into real-world settings is a high priority for education and public health. This paper describes the development of a partnership among the Houston Independent School District, the American Institutes of Research, and the Houston Federation of Teachers to support research on and program sustainability for the Good Behavior Game, a team-based classroom behavior management strategy that has shown positive impact in randomized field trials. The conceptual framework guiding partnership development is presented, followed by an application of the framework in Houston. Lessons learned and implications for the next stage of research and practice are then discussed
Enhanced recovery program in laparoscopic colectomy for cancer
Introduction: Both laparoscopic colectomy and application of enhanced recovery program (ERP) in open colectomy have been demonstrated to enable early recovery and to shorten hospital stay. This study evaluated the impact of ERP on results of laparoscopic colectomy and comparison was made with the outcomes of patients prior to the application of ERP. Methods: An ERP was implemented in the authors' center in December 2006. Short-term outcomes of consecutive 84 patients who underwent laparoscopic colonic cancer resection 23 months before (control group) and 96 patients who were operated within 13 months; after application of ERP (ERP group) were compared. Results: Between the ERP and control groups, there was no statistical difference in patient characteristics, pathology, operating time, blood loss, conversion rate or complications. Compared to the control group, patients in the ERP group had earlier passage of flatus [2 (range: 1-5) versus 2 (range: 1-4) days after operation respectively; p∈=∈0.03)] and a lower incidence of prolonged post-operative ileus (6% versus 0 respectively; p∈=∈0.02). There was no difference in the hospital stay between the two groups [4 (range: 2-34) days in control group and 4 (range: 2-23) days in ERP group; p∈=∈0.4)]. The re-admission rate was also similar (7% in control group and 5% in ERP group; p∈=∈0.59). Conclusions: In laparoscopic colectomy for cancer, application of ERP was associated with no increase in complication rate but significant improvement of gastrointestinal function. ERP further hastened patient recovery but resulted in no difference in hospital stay. © 2010 The Author(s).published_or_final_versionSpringer Open Choice, 31 May 201
Disparities in Healthcare Utilisation Rates for Aboriginal and Non-Aboriginal Albertan Residents, 1997-2006: A Population Database Study
Background: It is widely recognised that significant discrepancies exist between the health of indigenous and nonindigenous
populations. Whilst the reasons are incompletely defined, one potential cause is that indigenous communities
do not access healthcare to the same extent. We investigated healthcare utilisation rates in the Canadian Aboriginal
population to elucidate the contribution of this fundamental social determinant for health to such disparities.
Methods: Healthcare utilisation data over a nine-year period were analysed for a cohort of nearly two million individuals to
determine the rates at which Aboriginal and non-Aboriginal populations utilised two specialties (Cardiology and
Ophthalmology) in Alberta, Canada. Unadjusted and adjusted healthcare utilisation rates obtained by mixed linear and
Poisson regressions, respectively, were compared amongst three population groups - federally registered Aboriginals,
individuals receiving welfare, and other Albertans.
Results: Healthcare utilisation rates for Aboriginals were substantially lower than those of non-Aboriginals and welfare
recipients at each time point and subspecialty studied [e.g. During 2005/06, unadjusted Cardiology utilisation rates were
0.28% (Aboriginal, n = 97,080), 0.93% (non-Aboriginal, n = 1,720,041) and 1.37% (Welfare, n = 52,514), p = ,0.001]. The age
distribution of the Aboriginal population was markedly different [2.7%$65 years of age, non-Aboriginal 10.7%], and
comparable utilisation rates were obtained after adjustment for fiscal year and estimated life expectancy [Cardiology:
Incidence Rate Ratio 0.66, Ophthalmology: IRR 0.85].
Discussion: The analysis revealed that Aboriginal people utilised subspecialty healthcare at a consistently lower rate than
either comparatively economically disadvantaged groups or the general population. Notably, the differences were relatively
invariant between the major provincial centres and over a nine year period. Addressing the causes of these discrepancies is
essential for reducing marked health disparities, and so improving the health of Aboriginal people
Population structure and linkage disequilibrium unravelled in tetraploid potato
Association mapping is considered to be an important alternative strategy for the identification of quantitative trait loci (QTL) as compared to traditional QTL mapping. A necessary prerequisite for association analysis to succeed is detailed information regarding hidden population structure and the extent of linkage disequilibrium. A collection of 430 tetraploid potato cultivars, comprising two association panels, has been analysed with 41 AFLP® and 53 SSR primer combinations yielding 3364 AFLP fragments and 653 microsatellite alleles, respectively. Polymorphism information content values and detected number of alleles for the SSRs studied illustrate that commercial potato germplasm seems to be equally diverse as Latin American landrace material. Genome-wide linkage disequilibrium (LD)—reported for the first time for tetraploid potato—was observed up to approximately 5 cM using r2 higher than 0.1 as a criterion for significant LD. Within-group LD, however, stretched on average twice as far when compared to overall LD. A Bayesian approach, a distance-based hierarchical clustering approach as well as principal coordinate analysis were adopted to enquire into population structure. Groups differing in year of market release and market segment (starch, processing industry and fresh consumption) were repeatedly detected. The observation of LD up to 5 cM is promising because the required marker density is not likely to disable the possibilities for association mapping research in tetraploid potato. Population structure appeared to be weak, but strong enough to demand careful modelling of genetic relationships in subsequent marker-trait association analyses. There seems to be a good chance that linkage-based marker-trait associations can be identified at moderate marker densities
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