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1.
Animals (Basel) ; 13(19)2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37835692

RESUMO

It is unclear if piglets benefit from vaccination of sows against influenza. For the first time, methods of evidence-based medicine were applied to answer the question: "Does vaccine-induced maternally-derived immunity (MDI) protect swine offspring against influenza A viruses?". Challenge trials were reviewed that were published from 1990 to April 2021 and measured at least one of six outcomes in MDI-positive versus MDI-negative offspring (hemagglutination inhibition (HI) titers, virus titers, time to begin and time to stop shedding, risk of infection, average daily gain (ADG), and coughing) (n = 15). Screening and extraction of study characteristics was conducted in duplicate by two reviewers, with data extraction and assessment for risk of bias performed by one. Homology was defined by the antigenic match of vaccine and challenge virus hemagglutinin epitopes. Results: Homologous, but not heterologous MDI, reduced virus titers in piglets. There was no difference, calculated as relative risks (RR), in infection incidence risk over the entire study period; however, infection hazard (instantaneous risk) was decreased in pigs with MDI (log HR = -0.64, 95% CI: -1.13, -0.15). Overall, pigs with MDI took about a ½ day longer to begin shedding virus post-challenge (MD = 0.51, 95% CI: 0.03, 0.99) but the hazard of infected pigs ceasing to shed was not different (log HR = 0.32, 95% CI: -0.29, 0.93). HI titers were synthesized qualitatively and although data on ADG and coughing was extracted, details were insufficient for conducting meta-analyses. Conclusion: Homology of vaccine strains with challenge viruses is an important consideration when assessing vaccine effectiveness. Herd viral dynamics are complex and may include concurrent or sequential exposures in the field. The practical significance of reduced weaned pig virus titers is, therefore, not known and evidence from challenge trials is insufficient to make inferences on the effects of MDI on incidence risk, time to begin or to cease shedding virus, coughing, and ADG. The applicability of evidence from single-strain challenge trials to field practices is limited. Despite the synthesis of six outcomes, challenge trial evidence does not support or refute vaccination of sows against influenza to protect piglets. Additional research is needed; controlled trials with multi-strain concurrent or sequential heterologous challenges have not been conducted, and sequential homologous exposure trials were rare. Consensus is also warranted on (1) the selection of core outcomes, (2) the sizing of trial populations to be reflective of field populations, (3) the reporting of antigenic characterization of vaccines, challenge viruses, and sow exposure history, and (4) on the collection of non-aggregated individual pig data.

2.
Front Vet Sci ; 10: 1137774, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37065218

RESUMO

Background: Reporting of clinical trials conducted in client- and shelter-owned dog and cat populations is not optimal, which inhibits the ability to assess the reliability and validity of trial findings and precludes the ability to include some trials in evidence synthesis. Objective: To develop a reporting guideline for parallel group and crossover trials that addresses the unique features and reporting requirements for trials conducted in client- and shelter-owned dog and cat populations. Design: Consensus statement. Setting: Virtual. Participants: Fifty-six experts from North America, the United Kingdom, Europe, and Australia working in academia, government (research and regulatory agencies), industry, and clinical veterinary practice. Methods: A steering committee created a draft checklist for reporting criteria based upon the CONSORT statement and the CONSORT extensions for reporting of abstracts and crossover trials. Each item was presented to the expert participants and was modified and presented again until >85% of participants were in agreement about the inclusion and wording of each item in the checklist. Results: The final PetSORT checklist consists of 25 main items with several sub-items. Most items were modifications of items contained in the CONSORT 2010 checklist or the CONSORT extension for crossover trials, but 1 sub-item pertaining to euthanasia was created de novo. Conclusion: The methods and processes used to develop this guideline represent a novel departure from those used to create other reporting guidelines, by using a virtual format. The use of the PetSORT statement should improve reporting of trials conducted in client- and shelter-owned dogs and cats and published in the veterinary research literature.

3.
Front Vet Sci ; 10: 1137781, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37065227

RESUMO

Well-designed randomized controlled trials (RCTs) provide the best evidence of the primary research designs for evaluating the effectiveness of interventions. However, if RCTs are incompletely reported, the methodological rigor with which they were conducted cannot be reliably evaluated and it may not be possible to replicate the intervention. Missing information also may limit the reader's ability to evaluate the external validity of a trial. Reporting guidelines are available for clinical trials in human healthcare (CONSORT), livestock populations (REFLECT), and preclinical experimental research involving animals (ARRIVE 2.0). The PetSORT guidelines complement these existing guidelines, providing recommendations for reporting controlled trials in pet dogs and cats. The rationale and scientific background are explained for each of the 25 items in the PetSORT reporting recommendations checklist, with examples from well-reported trials.

4.
Front Vet Sci ; 9: 1004801, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36353256

RESUMO

Observational research may be conducted to predict an outcome or to identify associations between an intervention or risk factor (an "exposure") and an outcome. However, the end goal of observational research often is to identify exposures that can be manipulated to improve an outcome, meaning that the aim is identify causal relationships. Causal inference from observational studies may be appropriate when an exposure-outcome of interest is identified, causal reasoning is used to identify confounders, confounders are adequately controlled, and theoretical issues, such as temporality, are considered. If these conditions are not met, causal inference cannot be made in an observational study. The objective of our study was to explore the use of causal language in veterinary observational studies, and to compare the use of causal language between studies that appear to be predictive or associational in purpose vs. those that appear to be exploring causal relationships. The dataset comprised 200 observational studies in veterinary species published between 2020 and 2022. The majority (117 out of 200) were cross-sectional studies. There were 48 studies that described an exposure-outcome of interest, and we considered these studies to be exploring potential causal relationships; of note, this liberal categorization would be anticipated to overestimate the proportion of studies suitably designed for causal inference. Overall, 172 studies (86%) used causal wording in at least one section of the article. Causal language was used in 128/152 (84%) of studies exploring predictions or associations; this language implies causation when it is not appropriate to do so. In studies designed such that causal inference might be possible, 44/48 (92%) used causal language in one or more sections. There were no substantive differences in the use of causal wording between observational study designs, exposure types, or whether the first author's affiliation was a country in which English is an official language. There is a need for authors of veterinary observational studies to explicitly state the purpose of the study (associational, predictive, or causal), and to use causal wording appropriately based on the aim of the study.

5.
J Dairy Sci ; 105(11): 8594-8608, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36055845

RESUMO

Clinical trials are a valuable study design for evaluating interventions when it is ethical and feasible for investigators to randomly allocate study animals to intervention groups. Researchers may choose to evaluate the comparative efficacy of intervention groups for their effect on outcomes that are relevant to the specific objectives of their trial. However, the results across multiple trials on the same intervention and with the same outcome should be considered when making decisions on whether to use an intervention, because the results of a single trial are subject to sampling error and do not reflect all biological variability. The objective of this review was to provide an overview of important concepts when selecting intervention groups and outcomes within a randomized controlled trial, and when building a body of evidence for intervention efficacy across multiple trials. Empirical evidence is presented to highlight that integrating and interpreting the efficacy of an intervention across trials is hindered by a lack of replication of interventions across trials. Inconsistency in the outcomes and their measurement among trials also limits the ability to build a body of evidence for the efficacy of interventions. The development of core outcome sets for specific topic areas in dairy science, updated as necessary, may improve consistency across trials and aid in the development of a body of evidence for evidence-based decision-making.


Assuntos
Ensaios Clínicos Veterinários como Assunto , Projetos de Pesquisa , Animais , Bovinos
6.
Front Vet Sci ; 9: 960957, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35903128

RESUMO

Clinical decisions in human and veterinary medicine should be based on the best available evidence. The results of primary research are an important component of that evidence base. Regardless of whether assessing studies for clinical case management, developing clinical practice guidelines, or performing systematic reviews, evidence from primary research should be evaluated for internal validity i.e., whether the results are free from bias (reflect the truth). Three broad approaches to evaluating internal validity are available: evaluating the potential for bias in a body of literature based on the study designs employed (levels of evidence), evaluating whether key study design features associated with the potential for bias were employed (quality assessment), and applying a judgement as to whether design elements of a study were likely to result in biased results given the specific context of the study (risk of bias assessment). The level of evidence framework for assessing internal validity assumes that internal validity can be determined based on the study design alone, and thus makes the strongest assumptions. Risk of bias assessments involve an evaluation of the potential for bias in the context of a specific study, and thus involve the least assumptions about internal validity. Quality assessment sits somewhere between the assumptions of these two. Because risk of bias assessment involves the least assumptions, this approach should be used to assess internal validity where possible. However, risk of bias instruments are not available for all study designs, some clinical questions may be addressed using multiple study designs, and some instruments that include an evaluation of internal validity also include additional components (e.g., evaluation of comprehensiveness of reporting, assessments of feasibility or an evaluation of external validity). Therefore, it may be necessary to embed questions related to risk of bias within existing quality assessment instruments. In this article, we overview the approaches to evaluating internal validity, highlight the current complexities, and propose ideas for approaching assessments of internal validity.

7.
J Dairy Sci ; 105(7): 6155-6163, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35570046

RESUMO

Research allows for the discovery of new knowledge and is integral to evidence-based decision-making. However, research is only useful if it is available. The aim of this study was to explore publication and accessibility of full-text reports for controlled trials (experimental studies) conducted in dairy cattle. We determined the proportion of controlled trials presented as abstracts at the 2015 Joint Annual Meeting of the American Dairy Science Association and the American Society of Animal Science or the 2015 American Association of Bovine Practitioners Annual Conference that were subsequently published. Factors associated with publication or non-publication in a peer-reviewed journal were evaluated using risk ratios. For trials that were subsequently published, we compared the sample size, numerical results, and inference between the conference abstract and the subsequent publication. Approximately half of the trials (177 out of 380) reported at conferences were subsequently published. Source conference, whether the conference abstract results were described as preliminary, whether there was at least one positive outcome, author affiliation, whether the trial involved deliberate disease induction, and total sample size were not strongly associated with subsequent publication. For trials that were published, the sample size differed between the conference proceedings and full publications for 22%, the numerical results differed in 29%, and the inference differed for 11%. We also evaluated whether trials included in 9 recent systematic reviews were in English and were available without subscription or cost. Of the 390 trials included in recent systematic reviews, approximately 40% were available only through subscription or access fee. These results suggest that publication and accessibility of research results is suboptimal, representing an area of wastage in dairy cattle research. Researchers should ensure that they publish the results of trials comprehensively in searchable publications, even if the results are not novel or do not detect expected differences, and, when possible, make the results available freely.


Assuntos
Relatório de Pesquisa , Animais , Bovinos , Tamanho da Amostra , Estados Unidos
8.
BMC Res Notes ; 15(1): 187, 2022 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-35597997

RESUMO

OBJECTIVE: Person-to-person transmission can occur during outbreaks of verotoxigenic Escherichia coli (VTEC), however the impact of this transmission route is not well understood. This study aimed to examine the role of person-to-person transmission during a VTEC outbreak, and how targeting this route may reduce outbreak size. A deterministic compartmental model describing a VTEC outbreak was constructed and fit to data from a 2008 outbreak in Ontario, Canada. Using the best-fit model, simulations were run to calculate the: reduction in transmission rate after implementing interventions, proportion of cases infected through both transmission routes, and number of cases prevented by interventions. Latin hypercube sensitivity analysis was conducted to examine the sensitivity of the outbreak size to the model parameters. RESULTS: Based on the best-fit model, ~ 14.25% of the cases likely arose due to person-to-person transmission. Interventions reduced this transmission rate by ~ 73%, causing a reduction in outbreak size of ~ 17% (47 cases). Sensitivity analysis showed that the model was highly sensitive to changes in all parameters of the model. The model demonstrates that person-to-person could be an important transmission route during VTEC outbreaks. Targeting this route of transmission through hand hygiene and work exclusions could reduce the final outbreak size.


Assuntos
Infecções por Escherichia coli , Escherichia coli Shiga Toxigênica , Surtos de Doenças , Infecções por Escherichia coli/epidemiologia , Humanos , Ontário/epidemiologia
9.
Nutrients ; 14(8)2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35458135

RESUMO

The history of health research in Inuit communities in Canada recounts unethical and colonizing research practices. Recent decades have witnessed profound changes that have advanced ethical and community-driven research, yet much work remains. Inuit have called for research reform in Inuit Nunangat, most recently creating the National Inuit Strategy on Research (NISR) as a framework to support this work. The present study details the process undertaken to create a research program guided by the NISR to address food security, nutrition, and climate change in Inuit Nunangat. Four main elements were identified as critical to supporting the development of a meaningful and authentic community-led program of research: developing Inuit-identified research questions that are relevant and important to Inuit communities; identifying Inuit expertise to answer these questions; re-envisioning and innovating research methodologies that are meaningful to Inuit and reflect Inuit knowledge and societal values; and identifying approaches to mobilizing knowledge that can be applied to support food security and climate change adaptation. We also identify considerations for funding agencies to support the meaningful development of Inuit-led research proposals, including aligning funding with community priorities, reconsidering who the researchers are, and investing in community infrastructure. Our critical reflection on the research program development process provides insight into community-led research that can support Inuit self-determination in research, enhance local ethical conduct of research, privilege Inuit knowledge systems, and align Inuit-identified research priorities with research funding opportunities in health research. While we focus on Inuit-led research in Nunavut, Canada, these insights may be of interest more broadly to Indigenous health research.


Assuntos
Mudança Climática , Inuíte , Canadá , Segurança Alimentar , Humanos , Nunavut
10.
Zoonoses Public Health ; 69(1): 23-32, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34476904

RESUMO

Campylobacter is the second leading cause of foodborne illness in the United States. Although many food production animals carry Campylobacter as commensal bacteria, consumption of poultry is the main source of human infection. Previous research suggests that the biology of Campylobacter results in complete flock colonization within days. However, a recent systematic review found that the on-farm prevalence of Campylobacter varies widely, with some flocks reporting low prevalence. We hypothesized that the low prevalence of Campylobacter in some flocks may be driven by a delayed introduction of the pathogen. The objectives of this study were to (a) develop a deterministic compartmental model that represents the biology of Campylobacter, (b) identify the parameter values that best represent the natural history of the pathogen in poultry flocks and (c) examine the possibility that a delayed introduction of the pathogen is sufficient to replicate the observed low prevalence examples documented in the literature. A deterministic compartmental model was developed to examine the dynamics of Campylobacter in chicken flocks over a 56-day time period prior to movement to the abattoir. The model outcome of interest was the final population prevalence of Campylobacter at day 56. The resulting model that incorporated a high transmission rate (ß = 1.04) was able to reproduce the wide range of prevalence estimates observed in the literature when pathogen introduction time is varied. Overall, we established that the on-farm transmission rate of Campylobacter in chickens is likely high and can result in complete colonization of a flock when introduced early. However, delaying the time at which the pathogen enters the flock can reduce the prevalence observed at 56 days. These results highlight the importance of enforcing strict biosecurity measures to prevent or delay the introduction of the bacteria to a flock.


Assuntos
Infecções por Campylobacter , Campylobacter , Doenças das Aves Domésticas , Animais , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/veterinária , Galinhas/microbiologia , América do Norte , Doenças das Aves Domésticas/microbiologia , Prevalência
11.
Front Vet Sci ; 8: 727495, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34805332

RESUMO

The objective of this study was to describe the volume and nature of published literature on Salmonella in animal feeds using a formal scoping review methodology. A structured search followed by eligibility screening resulted in the identification of 547 relevant studies, encompassing studies conducted in the fields in which animal feeds are grown (15 studies), the manufacturing sector (106), during transportation (11), in the retail sector (15), and on-farm (226), with the sector not described for 204 studies. The most common study purposes were to estimate the prevalence of Salmonella in animal feeds (372 studies) and to identify serovars (195). The serovars that were found in animal feeds included serovars associated with human illness, with animal illness, and with serovars identified in food (livestock and poultry) intended for human consumption. There were 120 intervention studies and 83 studies conducted to evaluate potential risk factors. Within intervention and risk factor studies, there may be sufficient depth to warrant synthesis research in the areas of heat interventions, fermentation and ensiling, organic acids, season, and geographic region. Some deficiencies were identified in the completeness of reporting of key features in the relevant studies.

12.
Prev Vet Med ; 195: 105472, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34438246

RESUMO

Systematic reviews are a valuable tool for evaluating the efficacy of interventions and for quantifying associations. To be properly assessed, reviews must be comprehensively reported. The primary objective of this study was to evaluate the completeness of reporting of systematic reviews and meta-analyses in animal health. The secondary objective was to further characterize methods for literature searches and risk of bias assessments and to document whether the risk of bias component represented an assessment of risk of bias, study quality, or levels of evidence based on the primary studies included. The dataset comprised 91 systematic reviews or meta-analyses of interventions or exposures with at least one health outcome measured at the animal or animal byproduct level, in any companion or food animal species and published between 2014 and 2018. Two reviewers independently collected information on whether each item in the PRISMA reporting guidelines was reported, with disagreements resolved by consensus. There was considerable variability in the completeness of reporting among reviews; some items, such as eligibility criteria for inclusion, were reported in most reviews (>65 %). Other items were not consistently reported; for instance, in 60 % (54) of the reviews there was no information provided on the sample size of individual studies, populations, interventions and comparators, outcomes, or follow up period. Although 89 % (81) of systematic reviews with meta-analysis included the effect size estimate and confidence intervals, it was not possible to determine which study designs were included for 30 % (14) of reviews. Results from individual PRISMA item questions were combined to determine whether all aspects of each recommended item were reported; 71 % of items were adequately reported in less than half the systematic reviews without a meta-analysis, 35 % of the items were adequately reported in less than half the systematic reviews with a meta-analysis, and 71 % of items were adequately reported in less than half of the meta-analyses without a systematic review component. An assessment of individual study level bias was included in 64 % of the reviews, although this component included an evaluation of risk of bias (35 reviews), study quality (25 reviews), or levels of evidence based on study design (12 reviews). Reporting guidelines or clinical guidelines were inappropriately used to assess risk of bias in 9 reviews. Overall, the results of this study reveal that reporting of systematic reviews in the animal health literature is suboptimal and improvements are needed to enhance utility of these reviews.


Assuntos
Projetos de Pesquisa , Revisões Sistemáticas como Assunto/normas , Medicina Veterinária , Animais , Viés
13.
Epidemics ; 37: 100491, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34454353

RESUMO

INTRODUCTION: Zika virus (ZIKV) is primarily transmitted byAedes aegypti and Aedes albopictus mosquitoes between humans and non-human primates. Climate change may enhance virus reproduction in Aedes spp. mosquito populations, resulting in intensified ZIKV outbreaks. The study objective was to explore how an outbreak similar to the 2016 ZIKV outbreak in Brazil might unfold with projected climate change. METHODS: A compartmental infectious disease model that included compartments for humans and mosquitoes was developed to fit the 2016 ZIKV outbreak data from Brazil using least squares optimization. To explore the impact of climate change, published polynomial relationships between temperature and temperature-sensitive mosquito population and virus transmission parameters (mosquito mortality, development rate, and ZIKV extrinsic incubation period) were used. Projections for future outbreaks were obtained by simulating transmission with effects of projected average monthly temperatures on temperature-sensitive model parameters at each of three future time periods: 2011-2040, 2041-2070, and 2071-2100. The projected future climate was obtained from an ensemble of regional climate models (RCMs) obtained from the Co-Ordinated Regional Downscaling Experiment (CORDEX) that used Representative Concentration Pathways (RCP) with two radiative forcing values, RCP4.5 and RCP8.5. A sensitivity analysis was performed to explore the impact of temperature-dependent parameters on the model outcomes. RESULTS: Climate change scenarios impacted the model outcomes, including the peak clinical case incidence, cumulative clinical case incidence, time to peak incidence, and the duration of the ZIKV outbreak. Comparing 2070-2100 to 2016, using RCP4.5, the peak incidence was 22,030 compared to 10,473; the time to epidemic peak was 12 compared to 9 weeks, and the outbreak duration was 52 compared to 41 weeks. Comparing 2070-2100 to 2016, using RCP8.5, the peak incidence was 21,786 compared to 10,473; the time to epidemic peak was 11 compared to 9 weeks, and the outbreak duration was 50 compared to 41weeks. The increases are due to optimal climate conditions for mosquitoes, with the mean temperature reaching 28 °C in the warmest months. Under a high emission scenario (RCP8.5), mean temperatures extend above optimal for mosquito survival in the warmest months. CONCLUSION: Outbreaks of ZIKV in locations similar to Brazil are expected to be more intense with a warming climate. As climate change impacts are becoming increasingly apparent on human health, it is important to quantify the effect and use this knowledge to inform decisions on prevention and control strategies.


Assuntos
Aedes , Infecção por Zika virus , Zika virus , Animais , Brasil/epidemiologia , Surtos de Doenças , Mosquitos Vetores , Infecção por Zika virus/epidemiologia
14.
J Vet Intern Med ; 35(4): 1957-1971, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34184331

RESUMO

BACKGROUND: Comprehensive reporting of clinical trials is essential to allow the trial reader to evaluate the methodological rigor of the trial and interpret the results. Since publication of the updated Consolidated Standards of Reporting Trials (CONSORT) guidelines for reporting of parallel clinical trials in humans, extensions for reporting of abstracts and crossover trials have been published. OBJECTIVES: To describe the types of trials using dogs and cats published from 2015 to 2020 and to evaluate the quality of reporting of a sample of recently published parallel and crossover trials. ANIMALS: None. METHODS: A comprehensive search was conducted to identify parallel or crossover design clinical trials using dogs and cats published from January 1, 2015 onwards. Quality of reporting was evaluated on a subset of trials published during 2019. The reporting of items recommended in the CONSORT reporting guidelines for abstracts, parallel trials, and crossover trials was evaluated independently by 2 reviewers using standardized forms created for this study. Disagreements among reviewers were resolved by consensus. Results were tabulated descriptively. RESULTS: The frequency of reporting of trial features varied from low to high. There remain deficiencies in the quality of reporting of key methodological features and information needed to evaluate and interpret trial results. CONCLUSIONS AND CLINICAL IMPORTANCE: There is still a need for authors, peer-reviewers, and editors to follow reporting guidelines such as CONSORT to maximize the value of clinical trials and to increase confidence in the validity of the trial results.


Assuntos
Doenças do Gato , Doenças do Cão , Animais , Doenças do Gato/terapia , Gatos , Ensaios Clínicos Veterinários como Assunto , Consenso , Doenças do Cão/terapia , Cães , Padrões de Referência , Relatório de Pesquisa
15.
J Dairy Sci ; 104(9): 10143-10157, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34099288

RESUMO

The objective of this scoping review was to characterize all available literature on modifiable management practices used during the dry period that have been evaluated for their effects on udder health in dairy cattle during the dry period and the subsequent lactation. Five databases and two conference proceedings were searched for relevant literature. Articles published in or after 1990 were eligible for inclusion. Eligible interventions or exposures were restricted to modifiable management practices; however, antimicrobial and teat sealant products were enumerated but not further characterized, as systematic reviews have been published on this topic. Other modifiable management practices were reported in 229 articles. Nutrition (n = 79), which included ration formulation and delivery (n = 44) and vitamin and mineral additives (n = 35), was the most commonly reported practice, followed by vaccines (n = 40) and modification of dry period length (n = 27). Risk of clinical mastitis (CM) was the most commonly reported outcome (n = 151); however, reporting of outcome risk periods varied widely between articles. Cure of existing intramammary infections (IMI) over the dry period (n = 40) and prevention of new IMI over the dry period (n = 54) were most commonly reported with a risk period between calving and 30 d in milk. Future systematic reviews with meta-analyses could target management practices such as nutrition, vaccines, and dry period length to quantify their effects on improving udder health during the dry period and early lactation. However, the variation in reporting of time at risk for CM and other outcomes challenges the ability of future synthesis work to inform management decisions on the basis of efficacy to cure or prevent IMI and CM. Consensus on which core outcomes should be evaluated in mastitis research and the selection of consistent risk periods for specific outcomes in animal trials is imperative.


Assuntos
Doenças dos Bovinos , Mastite Bovina , Animais , Antibacterianos/uso terapêutico , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Contagem de Células/veterinária , Feminino , Lactação , Glândulas Mamárias Animais , Mastite Bovina/tratamento farmacológico , Mastite Bovina/prevenção & controle , Leite
16.
Front Vet Sci ; 8: 620347, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33969029

RESUMO

Swine producers are encouraged to practice antibiotic stewardship by reducing their use of antibiotics belonging to classes of medical importance to humans. We conducted a scoping review of non-antibiotic approaches in the form of products or management practices that might prevent or control disease and thus reduce the need for antibiotics in nursery pigs. Our objectives were to systematically describe the research on this broad topic for the North American context, identify specific topics that could feasibly support systematic reviews, and identify knowledge gaps. A search of multiple databases identified 11,316 articles and proceedings for relevance screening. From these, 441 eligible clinical trials and observational studies were charted. The majority were clinical trials (94%). Study results from EU countries were mostly communicated through journal articles, whereas study results from the USA were mostly communicated through conference proceedings. Interventions and health outcomes were diverse. The two most frequent intervention categories were feed additives and piglet vaccines. The three most frequent outcomes reported were diarrhea, mortality, and indices of vaccine immunity. There were 13 specific topics comprising various feed additives and vaccines that might feasibly support systematic reviews. There were relatively few studies in which interventions were compared with antibiotic comparison groups and relatively few studies evaluating management practices.

17.
Infect Dis Model ; 6: 664-677, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33997536

RESUMO

INTRODUCTION: Yellow fever (YF) is primarily transmitted by Haemagogus species of mosquitoes. Under climate change, mosquitoes and the pathogens that they carry are expected to develop faster, potentially impacting the case count and duration of YF outbreaks. The aim of this study was to determine how YF virus outbreaks in Brazil may change under future climate, using ensemble simulations from regional climate models under RCP4.5 and RCP8.5 scenarios for three time periods: 2011-2040 (short-term), 2041-2070 (mid-term), and 2071-2100 (long-term). METHODS: A compartmental model was developed to fit the 2017/18 YF outbreak data in Brazil using least squares optimization. To explore the impact of climate change, temperature-sensitive mosquito parameters were set to change over projected time periods using polynomial equations fitted to their relationship with temperature according to the average temperature for years 2011-2040, 2041-2070, and 2071-2100 for climate change scenarios using RCP4.5 and RCP8.5, where RCP4.5/RCP8.5 corresponds to intermediate/high radiative forcing values and to moderate/higher warming trends. A sensitivity analysis was conducted to determine how the temperature-sensitive parameters impacted model results, and to determine how vaccination could play a role in reducing YF in Brazil. RESULTS: Yellow fever case projections for Brazil from the models varied when climate change scenarios were applied, including the peak clinical case incidence, cumulative clinical case incidence, time to peak incidence, and the outbreak duration. Overall, a decrease in YF cases and outbreak duration was observed. Comparing the observed incidence in 2017/18 to the projected incidence in 2070-2100, for RCP4.5, the cumulative case incidence decreased from 184 to 161, and the outbreak duration decreased from 21 to 20 weeks. For RCP8.5, the peak case incidence decreased from 184 to 147, and the outbreak duration decreased from 21 to 17 weeks. The observed decrease was primarily due to temperature increasing beyond that suitable for Haemagogus mosquito survival. CONCLUSIONS: Climate change is anticipated to have an impact on mosquito-borne diseases. We found outbreaks of YF may reduce in intensity as temperatures increase in Brazil; however, temperature is not the only factor involved with disease transmission. Other factors must be explored to determine the attributable impact of climate change on mosquito-borne diseases.

18.
Zoonoses Public Health ; 68(6): 588-600, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33987921

RESUMO

Dogs are reservoirs for many zoonoses. In southern Ontario, Canada, minimal data exist on the sources from which domestic dogs are acquired (i.e., domestic or imported). The objectives of this study were to (1) describe the proportions of domestically sourced and imported dogs in southern Ontario, Canada, (2) describe the characteristics of newly acquired dogs including their province/country of origin, accompanying health documentation and respondent opinion regarding disease risks from different sources, and (3) determine whether a difference in the proportion of imported dogs exists between rural and urban households in southern Ontario, Canada. We conducted a cross-sectional observational study using an online questionnaire. A total of 2,006 respondents (1,002 rural and 1,004 urban), each representing one household, participated. Over the previous seven-year period, 731 (36.44%, (731/2,006)) respondents domestically sourced at least one dog, with 684 providing information regarding 962 dogs. Domestically sourced dogs were frequently puppies three to five-month-old (25.05%, (241/962)), male (51.87%, (499/962)), from a breeder (30.98%, (298/962)), and sourced from within Ontario (92.93%, (894/962)). As self-reported by respondents, 63.52% (484/762) of domestically sourced dogs greater than 3 months were vaccinated against rabies. Over the same period, individuals from 55 of 2,006 households (2.74%) imported at least one dog. Imported dogs were frequently under three months of age (29.09%, 16/55)), male (58.18%, (32/55)), and found via a breeder (32.73%, (18/55)). Most imported dogs originated from the USA (52.73%, (29/55)). Rabies vaccination in dogs three months and older is provincially required in Ontario and is also required for canine importation into Canada; however, some imported dogs over three months were unvaccinated (7.69%, (3/39)). The odds ratio for importing at least one dog in urban households compared with rural households was 1.93 (95% CI: 1.03-3.62) when controlling for number of household occupants and gross household income.


Assuntos
Comércio , Reservatórios de Doenças/veterinária , Doenças do Cão/prevenção & controle , Vacina Antirrábica , Raiva/veterinária , Animais , Estudos Transversais , Doenças do Cão/epidemiologia , Doenças do Cão/virologia , Cães , Feminino , Masculino , Razão de Chances , Ontário/epidemiologia , Raiva/epidemiologia , Raiva/prevenção & controle , Vacina Antirrábica/administração & dosagem , Vacina Antirrábica/imunologia , Inquéritos e Questionários , Viagem , Vacinação/legislação & jurisprudência , Zoonoses
19.
Artigo em Inglês | MEDLINE | ID: mdl-33807905

RESUMO

Inuit communities in the Circumpolar North have experienced a nutrition transition characterized by the decreased intake of culturally important, nutrient-rich traditional food (country food), and an increased intake of market food, resulting in concerns over reduced diet quality and emerging chronic diseases. Nutrition in early life is critical for development, may influence health risks in later life, and is an important concern for Inuit community health. The goal of this scoping review was to characterize the nature, extent, and range of the published literature on Inuit country food and health in pregnancy and childhood. A search string was developed and applied to three databases, followed by title and abstract screening and full text review. Articles published between 1995 and 2019 were included, and data were extracted and summarized descriptively. The number of articles generally increased over time, despite the unequal geographic distribution of articles. The majority of the articles focused on environmental contaminants, and one-quarter described nutrient adequacy. Few articles described food security or food safety in pregnancy, and the most utilized quantitative methods. Gaps in understanding of country food use in pregnancy and early childhood highlight areas of future research to support public health policy for this population. Given the critical role of good nutrition in early life and the important contribution country food makes to diet quality for Inuit, further understanding of this interface is warranted.


Assuntos
Dieta , Inuíte , Criança , Pré-Escolar , Feminino , Alimentos , Abastecimento de Alimentos , Humanos , Estado Nutricional , Gravidez
20.
Zoonoses Public Health ; 68(3): 277-283, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33655709

RESUMO

The prevalence of Toxoplasma gondii exposure in Inuit living in Nunavut (20%) is twice that of the US (11%); however, routes of exposure for Inuit communities in North America are unclear. Exposure to T. gondii in humans has been linked with consumption of raw or undercooked shellfish that can accumulate environmentally resistant oocysts. Bivalve shellfish, such as clams, are an important, nutritious, affordable and accessible source of food in many Northern Communities. To date, presence of T. gondii in clams in Northern Canada has not been reported. In this study, we tested for T. gondii presence in clams (Mya truncata) that were harvested in Iqaluit, Nunavut over a 1-week period in September 2016. Of 390 clams, eight (2.1%) were confirmed to contain T. gondii DNA (≥99.7% identity), as determined using polymerase chain reaction (PCR) and sequence confirmation. Additionally, three clams (0.8%) were confirmed to contain Neospora caninum-like DNA (≥99.2% identity). While N. caninum is not known to be a zoonotic pathogen, its presence in shellfish indicates contamination of the nearshore with canid faeces, and the potential for marine mammal exposure through marine food webs. Notably, the PCR assay employed in this study does not discriminate between viable and non-viable parasites. These findings suggest a possible route for parasite exposure through shellfish in Iqaluit, Nunavut. Future research employing viability testing will further inform public health messaging on the infectious potential of T. gondii in shellfish.


Assuntos
Bivalves/parasitologia , Parasitologia de Alimentos , Toxoplasma/isolamento & purificação , Toxoplasmose/transmissão , Animais , Sequência de Bases , Humanos , Nunavut/epidemiologia , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Toxoplasma/genética , Zoonoses
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