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1.
Contemp Clin Trials Commun ; 36: 101221, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38034842

RESUMO

Background: The coronavirus disease 2019 (COVID-19) global pandemic drastically impacted the health system and the research community. As a result, research institutions and funding agencies recommended a moratorium on conducting in-person research and study enrollment until protocol changes to protect participant safety were approved and implemented. We detail the operational modifications made to the Lupus Intervention Fatigue Trial (LIFT) protocol and summarize how we met the varied challenges created by COVID-19. Methods: We evaluated study protocols and determined that scheduling, acquiring consent, in-person assessments and intervention baseline visits, patient reported outcomes, and data processing procedures needed modification. Results: Operational modifications were made to ensure study progress while adhering to COVID-19 restrictions. Major changes included electronic consent, remote baseline visits for those in the intervention, self-report outcome measures at home via emailed weblinks, and telemedicine physician assessment visits. The collection of safety labs presented the largest challenge since this required an in-person visit to a laboratory. The study team elected to delay this up to one month after the physician assessment. All follow-up visits were completed, and no participants withdrew from the study. Conclusion: LIFT was severely impacted by COVID-19. We provide insight into how our study protocol was modified without compromising the integrity of the primary and secondary outcomes of the study. The modifications utilized by the LIFT study resulted in efficiencies that will be included in a revised protocol and may serve as a useful example for other behavioral interventions to adapt their research studies.

2.
J Subst Use Addict Treat ; 149: 209038, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37061190

RESUMO

INTRODUCTION: The prevalence of vaping among youth and young adults (YYAs; 16-18 and 19-24 years old, respectively) is moderate worldwide. Existing vaping cessation evidence lacks input from ex-vapers with a history of regular use and substantial maintenance periods. This study noted cessation strategies, relapse triggers, and recommendations for quitting identified by ex-vapers and assessed differences in outcomes across age and gender groups. METHODS: We recruited ex-vapers (N = 290; mean use = 6.5 days/week, SD = 1.05) with a minimum maintenance period of 30 days and a history of three months of consecutive use of nicotine-based devices from Nova Scotia, Canada. The ex-vapers responded to open-ended questions regarding vaping cessation strategies, triggers, and recommendations for quit strategies in an online survey. We coded responses to each topic (e.g., triggers) and grouped them into categories (e.g., social influences). We used chi-square tests and Bonferroni correction tests to determine group differences by topic and within each category. RESULTS: YYA ex-vapers identified cold turkey (28.9 %), self-restriction (27.5 %), and alternative coping mechanisms (19.0 %) as the most common cessation strategies; social influences (35.5 %,), mental state (18.3 %), and substance use (15.7 %) as the top triggers; and support systems (29.5 %), apps (17.3 %), and education (11.8 %) as the most useful recommendations for others. A higher proportion of female youth (51.3 %) identified social influences as a relapse trigger than male YAs (21.2 %) and female YAs (30.3 %). Further, male YAs (36.5 %) reported higher proportions of substance use as a relapse trigger than male youth (3.0 %) and female youth (2.6 %). Female youth (23.7 %) and YAs (22.6 %) recommended apps as a useful cessation strategy more often than male YAs (3.8 %). CONCLUSIONS: Input from ex-vapers can help to inform cessation practices, and gender and age differences shed light onto the need to tailor treatments, such as using social-centric behavioral therapy, for female youth and adopting a polysubstance substance use treatment approach for YAs.


Assuntos
Abandono do Hábito de Fumar , Vaping , Masculino , Humanos , Feminino , Adulto Jovem , Adolescente , Fumantes , Inquéritos e Questionários , Nova Escócia/epidemiologia
3.
Prev Med Rep ; 31: 102089, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36530454

RESUMO

The prevalence of electronic cigarettes (e-cigarettes) is increasing globally. Population-level data from several nations suggest that a higher proportion of youth and young adults are using e-cigarettes compared to the general population. Though significant work has been done in Western countries to better understand various aspects of e-cigarette use among youth and young adults, there is limited evidence about this phenomenon in Middle Eastern countries. This commentary summarizes the known aspects of youth and young adult e-cigarette use and the limitations of the evidence in the Middle East. Specifically, the limitations of the current literature indicate an overreliance on university-based samples, the overuse of non-user samples, a lack of studies on behaviour change, high variance in existing data, and a lack of uniform instruments to measure e-cigarette use. Lending from findings in other regions, we identify how these limitations should be addressed through future research to fill knowledge gaps in the Middle East.

4.
Microbiome ; 10(1): 131, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35996183

RESUMO

BACKGROUND: Top-soil microbiomes make a vital contribution to the Earth's ecology and harbor an extraordinarily high biodiversity. They are also key players in many ecosystem services, particularly in arid regions of the globe such as the African continent. While several recent studies have documented patterns in global soil microbial ecology, these are largely biased towards widely studied regions and rely on models to interpolate the microbial diversity of other regions where there is low data coverage. This is the case for sub-Saharan Africa, where the number of regional microbial studies is very low in comparison to other continents. RESULTS: The aim of this study was to conduct an extensive biogeographical survey of sub-Saharan Africa's top-soil microbiomes, with a specific focus on investigating the environmental drivers of microbial ecology across the region. In this study, we sampled 810 sample sites across 9 sub-Saharan African countries and used taxonomic barcoding to profile the microbial ecology of these regions. Our results showed that the sub-Saharan nations included in the study harbor qualitatively distinguishable soil microbiomes. In addition, using soil chemistry and climatic data extracted from the same sites, we demonstrated that the top-soil microbiome is shaped by a broad range of environmental factors, most notably pH, precipitation, and temperature. Through the use of structural equation modeling, we also developed a model to predict how soil microbial biodiversity in sub-Saharan Africa might be affected by future climate change scenarios. This model predicted that the soil microbial biodiversity of countries such as Kenya will be negatively affected by increased temperatures and decreased precipitation, while the fungal biodiversity of Benin will benefit from the increase in annual precipitation. CONCLUSION: This study represents the most extensive biogeographical survey of sub-Saharan top-soil microbiomes to date. Importantly, this study has allowed us to identify countries in sub-Saharan Africa that might be particularly vulnerable to losses in soil microbial ecology and productivity due to climate change. Considering the reliance of many economies in the region on rain-fed agriculture, this study provides crucial information to support conservation efforts in the countries that will be most heavily impacted by climate change. Video Abstract.


Assuntos
Microbiota , Solo , Biodiversidade , Clima Desértico , Ecossistema , Microbiota/genética , Solo/química , Microbiologia do Solo
5.
Plant Dis ; 105(10): 2914-2918, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33822659

RESUMO

Huanglongbing (HLB), caused by Candidatus Liberibacter asiaticus, is currently the most destructive disease of citrus and threatens production in all affected areas. There is no cure. Benign Xylella fastidiosa strain EB92-1 provided good control of Pierce's disease of grapevine by inducing host resistance; therefore, we evaluated the strain for the biological control of HLB in citrus. Treatment was by injection into the trunk of the trees. Strain EB92-1 was shown to colonize citrus and provided control of HLB by reducing both the incidence of symptomatic trees and the percentage of trees with severe symptoms in three separate trials. All trees were positive by quantitative PCR (qPCR) for Candidatus Liberibacter asiaticus at the start of the trials, and treatment did not eliminate the bacterium. In a trial of asymptomatic mature trees, a single treatment with EB92-1 reduced the incidence of trees with symptoms through 18 months after treatment and reduced the incidence of trees with severe symptoms through 3 years. In mature trees that had 60% incidence of mild HLB symptoms at trial initiation, percentage of trees with symptoms and trees with severe symptoms continued to develop in both the untreated and in the EB92-1-treated trees for 12 months. However, retreatment at 9 and 20 months prevented the development of additional severe symptoms in the EB92-1-treated trees throughout the remainder of the 5-year trial. In 2-year-old trees, incidence of trees with HLB symptoms was higher in the untreated trees than in the treated trees throughout the 6 years of the trial, reaching 90% in the untreated versus 50% in the treated. After 6 years, severity of symptoms was much lower in the EB92-1-treated trees, only 3% of the treated trees had become unproductive compared with 18% of the untreated. In 2020, the reduction in HLB severity resulted in approximately twice as much yield in the treated trees as in these untreated 8-year-old trees. X. fastidiosa strain EB92-1 proved to be efficacious for the control of HLB symptoms in both mature trees and newly planted young trees, but trees may need to be retreated yearly for at least the first 2 to 3 years.


Assuntos
Citrus , Rhizobiaceae , Xylella , Doenças das Plantas/prevenção & controle , Rhizobiaceae/genética , Xylella/genética
6.
Horm Metab Res ; 53(3): 204-206, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33652492

RESUMO

Currently, we are experiencing a true pandemic of a communicable disease by the virus SARS-CoV-2 holding the whole world firmly in its grasp. Amazingly and unfortunately, this virus uses a metabolic and endocrine pathway via ACE2 to enter our cells causing damage and disease. Our international research training programme funded by the German Research Foundation has a clear mission to train the best students wherever they may come from to learn to tackle the enormous challenges of diabetes and its complications for our society. A modern training programme in diabetes and metabolism does not only involve a thorough understanding of classical physiology, biology and clinical diabetology but has to bring together an interdisciplinary team. With the arrival of the coronavirus pandemic, this prestigious and unique metabolic training programme is facing new challenges but also new opportunities. The consortium of the training programme has recognized early on the need for a guidance and for practical recommendations to cope with the COVID-19 pandemic for the community of patients with metabolic disease, obesity and diabetes. This involves the optimal management from surgical obesity programmes to medications and insulin replacement. We also established a global registry analyzing the dimension and role of metabolic disease including new onset diabetes potentially triggered by the virus. We have involved experts of infectious disease and virology to our faculty with this metabolic training programme to offer the full breadth and scope of expertise needed to meet these scientific challenges. We have all learned that this pandemic does not respect or heed any national borders and that we have to work together as a global community. We believe that this transCampus metabolic training programme provides a prime example how an international team of established experts in the field of metabolism can work together with students from all over the world to address a new pandemic.


Assuntos
COVID-19 , Diabetes Mellitus , Educação Médica Continuada , Obesidade , Pandemias , SARS-CoV-2 , COVID-19/epidemiologia , COVID-19/terapia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia , Humanos , Obesidade/epidemiologia , Obesidade/terapia
7.
J Adolesc Health ; 68(4): 787-793, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32943292

RESUMO

PURPOSE: This study examined differences in the topics of vaping perceptions (positive and negative aspects) and experiences (social media content) among e-cigarette users segmented by age and gender (male and female youth and young adults) and tobacco use (never, former, or current user). METHOD: E-cigarette users (N = 558, 53.6% male, mean age: 18.6 years [SD = 2.2], mean use: 5.3 days/week [SD = 2.3]) residing in Nova Scotia, Canada, responded to three open-ended topic questions concerning vaping in an online survey. Responses to each topic (e.g., positive aspects) were coded and grouped into categories (e.g., flavors). Chi-square tests were used to examine whether groups differed by topic, and Bonferroni correction tests were used to determine specific group differences in each coded category. RESULTS: Age and gender groups differed in their positive perceptions of a nicotine rush, tricks, and positive social aspects of vaping and in their negative perceptions of respiratory effects, nicotine effects, product malfunction and cost, and negative social aspects of vaping. Age and gender groups also differed in exposure to tricks and branding on social media. Tobacco use groups differed in their positive perceptions of flavor, nicotine rush, tricks, low cost, enhancement, and smoking cessation and in their negative perceptions of negative social aspects and exposure to tricks on social media. CONCLUSIONS: There are notable similarities and differences among youth and young adult e-cigarette users by age, gender, and tobacco use. Policies and interventions should incorporate these distinctions to effectively address the increasing use of e-cigarettes among young users.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Vaping , Adolescente , Canadá , Feminino , Humanos , Masculino , Percepção , Uso de Tabaco , Adulto Jovem
8.
Diabet Med ; 37(7): 1090-1093, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32369634

RESUMO

The National Diabetes Stakeholders Covid-19 Response Group was formed in early April 2020 as a rapid action by the Joint British Diabetes Societies for Inpatient Care, Diabetes UK, the Association of British Clinical Diabetologists, and Diabetes Frail to address and support the special needs of residents with diabetes in UK care homes during Covid-19. It was obvious that the care home sector was becoming a second wave of Covid-19 infection and that those with diabetes residing in care homes were at increased risk not only of susceptibility to infection but also to poorer outcomes. Its key purposes included minimising the morbidity and mortality associated with Covid-19 and assisting care staff to identify those residents with diabetes at highest risk of Covid-19 infection. The guidance was particularly created for care home managers, other care home staff, and specialist and non-specialist community nursing teams. The guidance covers the management of hyperglycaemia by discussion of various clinical scenarios that could arise, the management of hypoglycaemia, foot care and end of life care. In addition, it outlines the conditions where hospital admission is required. The guidance should be regarded as interim and will be updated as further medical and scientific evidence becomes available.


Assuntos
Infecções por Coronavirus/terapia , Atenção à Saúde/métodos , Diabetes Mellitus/terapia , Casas de Saúde , Pneumonia Viral/terapia , Betacoronavirus , COVID-19 , Comorbidade , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/metabolismo , Complicações do Diabetes/epidemiologia , Diabetes Mellitus/epidemiologia , Gerenciamento Clínico , Fragilidade , Glucocorticoides/uso terapêutico , Humanos , Expectativa de Vida , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/metabolismo , Fatores de Risco , SARS-CoV-2 , Reino Unido/epidemiologia
9.
Front Public Health ; 8: 620748, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33585389

RESUMO

The aim of this study was to test how youth and young adult e-cigarette users responded to the COVID-19 pandemic. The 2020 Youth and Young Adult Vaping Survey (N = 1,308) included 540 (44.7%) participants that reported differences in their vaping behaviors since the onset of the pandemic. Gender was the only relevant covariate that yielded a significant effect and/or interaction through a multivariate test. A two-way multivariate analysis of variance was used to test the effect of pandemic onset (pre- vs. during-pandemic), gender (males vs. females), and their interaction on vaping behaviors (days of vaping per week, episodes of vaping per day, and puffs per vaping episode). Respondents reported fewer days of vaping per week, episodes of vaping per day, and puffs per vaping episode during-pandemic than pre-pandemic [F (3,533) = 52.81, p < 0.001, η p 2 = 0.229]. The multivariate effect of gender on the three vaping outcomes was not statistically significant [F (3, 533) = 2.14, p = 0.095, η p 2 = 0.012], though the interaction between pandemic onset and gender was [F (3, 533) = 2.86, p = 0.036, η p 2 = 0.016]. Males reported fewer episodes of vaping per day [t (262) = 7.40, p < 0.001, 95% CI: 5.19-8.97] and puffs per vaping episode [t (263) = 3.23, p = 0.001, 95% CI:0.292-1.20] during-pandemic than pre-pandemic. Females reported fewer vaping episodes per day during-pandemic than pre-pandemic [t (273) = 5.14, p < 0.001, 95% CI: 2.76-6.18]. Further, females reported more frequent puffs per vaping episode in comparison to males during-pandemic [t (538) = -2.38, p = 0.017, 95% CI: -2.09-0.200]. The COVID-19 pandemic presents an opportunity to reduce vaping through health promotion messaging. Since females take more puffs per vaping episode overall, they may benefit the most from greater vaping cessation supports.


Assuntos
COVID-19 , Sistemas Eletrônicos de Liberação de Nicotina/estatística & dados numéricos , Vaping/epidemiologia , Adolescente , Análise de Variância , COVID-19/epidemiologia , COVID-19/mortalidade , Canadá/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Análise Multivariada , Fatores de Risco , Fatores Sexuais , Inquéritos e Questionários , Adulto Jovem
10.
Extremophiles ; 24(1): 17-29, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31376000

RESUMO

The Namib Desert is one of the world's only truly coastal desert ecosystem. Until the end of the 1st decade of the twenty-first century, very little was known of the microbiology of this southwestern African desert, with the few reported studies being based solely on culture-dependent approaches. However, from 2010, an intense research program was undertaken by researchers from the University of the Western Cape Institute for Microbial Biotechnology and Metagenomics, and subsequently the University of Pretoria Centre for Microbial Ecology and Genomics, and their collaborators, led to a more detailed understanding of the ecology of the indigenous microbial communities in many Namib Desert biotopes. Namib Desert soils and the associated specialized niche communities are inhabited by a wide array of prokaryotic, lower eukaryotic and virus/phage taxa. These communities are highly heterogeneous on both small and large spatial scales, with community composition impacted by a range of macro- and micro-environmental factors, from water regime to soil particle size. Community functionality is also surprisingly non-homogeneous, with some taxa retaining functionality even under hyper-arid soil conditions, and with subtle changes in gene expression and phylotype abundances even on diel timescales. Despite the growing understanding of the structure and function of Namib Desert microbiomes, there remain enormous gaps in our knowledge. We have yet to quantify many of the processes in these soil communities, from regional nutrient cycling to community growth rates. Despite the progress that has been made, we still have little knowledge of either the role of phages in microbial community dynamics or inter-species interactions. Furthermore, the intense research efforts of the past decade have highlighted the immense scope for future microbiological research in this dynamic, enigmatic and charismatic region of Africa.


Assuntos
Ecossistema , Bactérias , Clima Desértico , Solo , Microbiologia do Solo
11.
Diabet Med ; 37(12): 1992-2000, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-31833586

RESUMO

AIM: To examine the challenges healthcare teams face when treating people with type 1 diabetes and disordered eating and the strategies these teams have developed to facilitate effective treatment. METHODS: Four semi-structured focus groups were conducted including two tertiary diabetes specialist teams and three tertiary eating disorders specialist teams between July and December 2018. Thematic analysis of the transcripts followed a six-phase process. RESULTS: Twenty-nine experienced healthcare professionals (16 diabetes and 13 eating disorder specialists, 16±12 years' professional experience) were interviewed. The challenges identified in treating people with type 1 diabetes and disordered eating included subthemes the 'challenges specific to the healthcare professional' (feeling not competent enough and perceived emotional burden), 'challenges pertaining to patient factors' (e.g. difficulties with engaging in therapy) and 'challenges created by the healthcare system' (time pressure and staff shortage). Healthcare professionals expressed the need for a consensus on diagnosis and the definition of disordered eating in type 1 diabetes, as well as the need for training and educational resources specific to type 1 diabetes and disordered eating. Healthcare professionals gave practical examples of strategies of communication for better patient engagement and felt that multidisciplinary working in joint clinics with the other specialty were facilitators for recovery from disordered eating. CONCLUSIONS: Healthcare professionals require multidisciplinary team support when treating people with type 1 diabetes and to improve their own competencies. The development of effective screening and assessment tools, educational resources and training for healthcare professionals, and developing multidisciplinary treatment pathways will be key to improving outcomes for their service users with type 1 diabetes and disordered eating.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Diabulimia/reabilitação , Atitude do Pessoal de Saúde , Diabetes Mellitus Tipo 1/psicologia , Diabulimia/diagnóstico , Diabulimia/psicologia , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Transtornos da Alimentação e da Ingestão de Alimentos/reabilitação , Grupos Focais , Humanos , Equipe de Assistência ao Paciente
12.
J Public Health Policy ; 41(1): 63-69, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31664162

RESUMO

The use of e-cigarettes, otherwise known as 'vaping', has been increasing at alarming rates among youth and young adults. Although the long-term harms of vaping are still unclear, emerging evidence brings to light potential risks associated with vaping, especially for youth and non-smokers. This paper discusses nine viable policy measures that could limit the appeal of vaping products to youth and young adults and, in turn, reduce the potential harms of vaping.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Política Pública , Indústria do Tabaco/legislação & jurisprudência , Vaping , Adolescente , Regulamentação Governamental , Humanos , Abandono do Hábito de Fumar , Adulto Jovem
13.
Meat Sci ; 157: 107870, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31252375

RESUMO

Data from samples of longissmus lumborum (LL) and semimembranosus (SM) muscles from 391 lamb carcasses, which had been packaged in overwrap (OW) or high oxygen modified atmosphere packaging (MAPO2) systems and then subjected to simulated retail display, were used to estimate genetic variation for colour stability traits of lamb meat as a step in identifying a trait for genetic evaluation. Traits included the ratio of the reflectance of light at wavelengths of 630 nm and 580 nm (oxy/met) measured at a single time point at the end of the display period (day 3 under OW; day 8 under MAPO2) and the predicted time for oxy/met to reach a benchmark value. Under OW and MAPO2, the measures of meat colour stability of the LL tended to be of moderate heritability (0.09-0.29), but for the SM were of low heritability (0-0.10). Improving retail colour stability of lamb loins through selection of genetically superior animals may be better based on measurement of oxy/met.


Assuntos
Cor , Embalagem de Alimentos/métodos , Carne Vermelha/análise , Animais , Variação Genética , Músculo Esquelético/química , Oxigênio , Carneiro Doméstico
14.
Meat Sci ; 148: 105-112, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30388474

RESUMO

Dietary supplementation of vitamin E (VitE) in a synthetic or natural form was examined. Forty-eight lambs were assigned (n = 16) to either a grain-based diet at moderate (MOD, 42 mg∙kg-1 VitE as all-rac α-tocopheryl acetate) or supranutritional (SUP, 285 mg∙kg-1 of vitE) levels of synthetic VitE or a lucerne hay-based diet (LUC; 37 mg∙kg-1 VitE) for 8 weeks. Meat from the LUC group had lower muscle n-6 and PUFA levels compared to meat from the MOD and SUP groups. Despite a similar VitE intake, muscle VitE was higher for LUC compared to MOD, while SUP lambs showed the highest VitE. Lipid oxidation did not differ between groups. For fresh meat, redness tended to be higher in LUC fed lambs than the other two groups, but brownness formation was only lower than the SUP group. For aged meat colour stability, redness tended to be higher in lambs fed SUP and LUC, whereas highest browning occurred in the MOD group.


Assuntos
Ração Animal/análise , Ácidos Graxos/análise , Carne Vermelha/análise , Carneiro Doméstico/fisiologia , Animais , Cor , Dieta/veterinária , Grão Comestível , Feminino , Masculino , Medicago sativa , Músculo Esquelético/química , Oxirredução , Vitamina E
15.
Rev Sci Tech ; 37(1): 57-70, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30209429

RESUMO

This review discusses the importance of red meat from ruminants as a source of omega-3 (n-3) fatty acids (FAs) for human life in the context of the contribution of animals to human welfare. Red meat is a valuable food commodity for human life because it is naturally rich in key nutrients such as protein, trace elements, vitamins and essential FAs. In developed countries and high socio-economic groups from developing countries, red meat intake is greater than that of oily fish, owing to availability, preference and affordability. Omega-3 FA concentration is higher in red meat (beef, lamb and mutton) than in white meat (pork, poultry and turkey), due to the fibre types present in muscle tissues and the specialised digestive systems of ruminants. There is mounting evidence that regular consumption of n-3 FAs is beneficial for growth and development as well as the health and welfare of humans of all ages. The dietary background of ruminants significantly influences the concentration of n-3 FAs in red meat. Meat from forage- or grassfed ruminants has a greater concentration of n-3 FAs than that from their feedlot or grain-fed counterparts and can also offer a favourable n-6:n-3 ratio in the meat. Scientific literature shows that the advantages of consuming n-3 FAs enriched meat (foods) outweigh the disadvantages.


Dans le cadre de l'analyse de la contribution des animaux au bien-être de l'homme, les auteurs examinent l'importance pour l'alimentation humaine des acides gras oméga-3 présents dans la viande rouge provenant de ruminants. La viande rouge est une denrée alimentaire précieuse pour l'organisme humain, étant naturellement riche en plusieurs nutriments majeurs tels que protéines, oligo-éléments, vitamines et acides gras essentiels. Dans les pays développés et dans les classes aisées au plan socio-économique des pays en développement, la consommation de viande rouge dépasse celle de poissons gras pour des raisons de disponibilité, de préférence et de prix. La teneur en acides gras oméga-3 est plus élevée dans les viandes rouges (boeuf, agneau et mouton) que dans les viandes blanches (porc, volaille et dinde) du fait des caractéristiques des fibres des tissus musculaires des ruminants et de leur système digestif spécialisé. Il y a de plus en plus d'indices démontrant qu'une consommation régulière d'acides gras oméga-3 est bénéfique pour la croissance et le développement ainsi que pour la santé et le bien-être de l'être humain à tous les âges de sa vie. Le contexte de l'alimentation des ruminants influence de manière significative la teneur en acides gras oméga-3 de la viande rouge. La viande issue de ruminants nourris de fourrage ou à l'herbe présente une concentration plus élevée d'acides gras oméga-3 que celle de leurs homologues des parcs d'engraissement ou nourris au grain, ainsi qu'un ratio oméga 6/oméga-3 favorable. La littérature scientifique montre que la consommation de viandes (ou autres aliments) riches en acides gras oméga-3 apporte plus de bénéfices que d'inconvénients.


Considerando la cuestión desde el ángulo de la contribución de los animales al bienestar humano, los autores examinan la importancia que reviste para la vida humana la carne roja de rumiante como fuente de ácidos grasos omega-3 (n-3). Por su elevado contenido natural en nutrientes fundamentales como proteínas, oligoelementos, vitaminas y ácidos grasos esenciales, la carne roja es un artículo alimentario de gran valor para la vida humana. En los países desarrollados, al igual que entre las élites socioeconómicas de los países en desarrollo, la ingesta de carne roja es superior a la de pescado azul, por razones de disponibilidad, preferencia y asequibilidad. Por los tipos de fibra presentes en el tejido muscular de los rumiantes y por el carácter especializado de su sistema digestivo, la concentración de ácidos grasos omega-3 es mayor en la carne roja (bovinos y ovinos) que en la carne blanca (cerdo, pollo y pavo). Cada vez hay más datos demostrativos de que el consumo regular de ácidos grasos n-3 es beneficioso para el crecimiento, el desarrollo, la salud y el bienestar de las personas a cualquier edad. El tipo de alimentación de un rumiante influye sensiblemente en la concentración de ácidos grasos n-3 que presentará su carne: la carne de rumiantes que han forrajeado o pastado en campos de hierba tiene mayor concentración de esos ácidos grasos que la de sus homólogos procedentes de establos de engorde o alimentados con grano, además de presentar en ocasiones una proporción más favorable entre n-6 y n-3. Los estudios científicos publicados ponen de relieve que el consumo de carne (u otros alimentos) enriquecida en ácidos grasos n-3 tiene más ventajas que inconvenientes.


Assuntos
Ração Animal , Criação de Animais Domésticos , Ácidos Graxos Ômega-3/química , Carne/análise , Animais , Ácidos Graxos Ômega-3/metabolismo , Ruminantes
16.
J Anim Sci ; 95(10): 4260-4273, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29108061

RESUMO

Genetic correlations between 29 wool production and quality traits and 25 meat quality and nutritional value traits were estimated for Merino sheep from an Information Nucleus (IN). Genetic correlations among the meat quality and nutritional value traits are also reported. The IN comprised 8 flocks linked genetically and managed across a range of sheep production environments in Australia. The wool traits included over 5,000 yearling and 3,700 adult records for fleece weight, fiber diameter, staple length, staple strength, fiber diameter variation, scoured wool color, and visual scores for breech and body wrinkle. The meat quality traits were measured on samples from the and included over 1,200 records from progeny of over 170 sires for intramuscular fat (IMF), shear force of meat aged for 5 d (SF5), 24 h postmortem pH (pHLL; also measured in the , pHST), fresh and retail meat color and meat nutritional value traits such as iron and zinc levels, and long-chain omega-3 and omega-6 polyunsaturated fatty acid levels. Estimated heritabilities for IMF, SF5, pHLL, pHST, retail meat color lightness (), myoglobin, iron, zinc and across the range of long-chain fatty acids were 0.58 ± 0.11, 0.10 ± 0.09, 0.15 ± 0.07, 0.20 ± 0.10, 0.59 ± 0.15, 0.31 ± 0.09, 0.20 ± 0.09, 0.11 ± 0.09, and range of 0.00 (eicosapentaenoic, docosapentaenoic, and arachidonic acids) to 0.14 ± 0.07 (linoleic acid), respectively. The genetic correlations between the wool production and meat quality traits were low to negligible and indicate that wool breeding programs will have little or no effect on meat quality. There were moderately favorable genetic correlations between important yearling wool production traits and the omega-3 fatty acids that were reduced for corresponding adult wool production traits, but these correlations are unlikely to be important in wool/meat breeding programs because they have high SE, and the omega-3 traits have little or no genetic variance. Significant genetic correlations among the meat quality traits included IMF with SF5 (-0.76 ± 0.24), fresh meat color * (0.50 ± 0.18), and zinc (0.41 ± 0.19). Selection to increase IMF will improve meat tenderness and color which may address some of the issues with Merino meat quality. These estimated parameters allow Merino breeders to combine wool and meat objectives without compromising meat quality.


Assuntos
Carne/normas , Ovinos/genética , Lã/normas , Animais , Austrália , Peso Corporal/genética , Cruzamento , Cor , Ácidos Graxos/análise , Feminino , Ferro/análise , Masculino , Valor Nutritivo/genética , Fenótipo , Ovinos/fisiologia , Zinco/análise
17.
Meat Sci ; 134: 124-127, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28783608

RESUMO

The current study examined the effect of vascular rinsing lamb carcases (Rinse & Chill®) with a commercially available isotonic substrate solution (98.5% water; balance: glucose, polyphosphates, and maltose) at 14°C. Thirty, lamb carcases were randomly allocated to receive either the solution (n=15) 25 min post slaughter on a slaughter line or no solution (n=15). There was no apparent effect on the rate of pH decline due to infusion or muscle shortening of the M. longissimus thoracis et lumborum (LL), but there was a more than 50% reduction in toughness (lower shear force) of the LL due to infusion. Infusion resulted in lighter (L*), yellower (b*) LL and this effect was maintained during simulated colour display. There was no impact on redness (a*) of the LL and in fact a critical consumer threshold for redness was not breached on average for infused or non-infused LL. There was no evidence of elevated levels of metmyoglobin formation or lipid oxidation.


Assuntos
Glucose/administração & dosagem , Maltose/administração & dosagem , Polifosfatos/administração & dosagem , Carne Vermelha/análise , Matadouros , Animais , Cor , Manipulação de Alimentos/métodos , Glucose/farmacologia , Concentração de Íons de Hidrogênio , Infusões Intravenosas/veterinária , Lipídeos , Maltose/farmacologia , Metamioglobina/análise , Músculo Esquelético/química , Oxirredução , Polifosfatos/farmacologia , Carne Vermelha/normas , Carneiro Doméstico , Soluções
18.
J Anim Sci ; 95(6): 2385-2398, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28727038

RESUMO

Genetic correlations between 29 wool production and quality traits and 14 whole carcass measures and carcass component traits were estimated from the Information Nucleus of 8 flocks managed across a range of Australian sheep production environments and genetically linked. Wool data were from over 5,000 Merino progeny born over 5 yr, whereas carcass data were from over 1,200 wether progeny of over 176 sires, slaughtered at about 21 kg carcass weight, on average. Wool traits included yearling and adult records for wool weight, fiber diameter, fiber diameter variation, staple strength, scoured color, and visual scores for breech and body wrinkle. Whole carcass measures included HCW, dressing percentage (DP), and various measures of fat depth and eye muscle dimensions. Carcass components were obtained by dissection, and lean meat yield (LMY) was predicted. Heritability estimates for whole carcass measures ranged from 0.12 ± 0.08 to 0.35 ± 0.10 and ranged from 0.17 ± 0.10 to 0.46 ± 0.10 for carcass dissection traits, with no evidence of important genotype × environment interactions. Genetic correlations indicated that selection for increased clean wool weight will result in reduced carcass fat (-0.17 to -0.34) and DP (-0.48 ± 0.15), with little effect on carcass muscle. Selection for lower fiber diameter will reduce HCW (-0.48 ± 0.15) as well as carcass fat (0.14 to 0.27) and muscle (0.21 to 0.50). There were high genetic correlations between live animal measures of fat and muscle depth and the carcass traits (generally greater than 0.5 in size). Selection to increase HCW (and DP) will result in sheep with fewer wrinkles on the body (-0.57 ± 0.10) and barer breeches (-0.74 ± 0.12, favorable), with minor deterioration in scoured wool color (reduced brightness and increased yellowness). Selection for reduced fat will also result in sheep with fewer body wrinkles (-0.42 to -0.79). Increasing LMY in Merinos through selection would result in a large reduction in carcass fat and DP (-0.66 to -0.84), with a smaller increase in carcass muscle and some increase in wool weight and wrinkles. Although no major antagonisms are apparent between the wool and carcass traits, developing selection indexes for dual-purpose wool and meat breeding objectives will require accurate estimates of genetic parameters to ensure that unfavorable relationships are suitably considered. The findings will aid development of dual-purpose wool and meat breeding objectives.


Assuntos
Ovinos/genética , Lã/crescimento & desenvolvimento , Animais , Austrália , Peso Corporal , Cruzamento , Cor , Feminino , Genótipo , Masculino , Fenótipo , Carne Vermelha , Ovinos/crescimento & desenvolvimento
19.
J Anim Sci ; 95(7): 3012-3024, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28727089

RESUMO

This study was conducted to determine whether circulating concentrations of blood isoprostanes can be used as an effective biomarker in lambs to predict degradation of color and/or lipid stability in meat. Lambs ( = 84) were fed diets of either lucerne pasture, annual ryegrass pasture, a commercial feedlot pellet, or a combination of annual ryegrass and feedlot pellet for 8 wk, including a 2-wk adaptation period. Blood isoprostane concentration at wk 0, 4, 6 or 8 of feeding was determined. Blood isoprostane concentration for each animal was then correlated with muscle biochemical components that impact color and/or lipid oxidative status during retail display. This included lipid oxidation levels in muscle assessed by thiobarbituric acid reactive substances and meat redness determined by a HunterLab colorimetric spectrometer. Lambs that consumed the commercial feedlot pellet had a lower muscle vitamin E level (< 0.01) and a greater level of -6 PUFA ( < 0.001) compared with lambs finished on annual ryegrass or lucerne. Lipid oxidation levels were greatest for lambs finished on the feedlot ration, lowest in lambs finished on the ryegrass diet, and intermediate for lambs finished on lucerne and ryegrass-feedlot combination ( < 0.01). After 8 wk of feeding, blood isoprostane concentration was positively correlated with lipid oxidation of meat displayed for 72 h in simulated retail conditions ( < 0.01). There was a negative linear relationship between isoprostane concentration and muscle vitamin E concentration ( = 0.07), lipid oxidation and muscle vitamin E concentration ( < 0.01) but a positive linear relationship between isoprostane concentration and muscle -6 PUFA ( < 0.001) or lipid oxidation and muscle -6 PUFA concentration ( < 0.001). Blood isoprostane concentration and lipid oxidation in meat were influenced by muscle vitamin E and -6 PUFA but not by -3 PUFA. There was no significant relationship observed between blood isoprostane concentration at 0, 4, 6 or 8 wk feeding vs. overall meat color (redness of meat) at 0 and 72 h of display, stored under simulated retail conditions. The results indicate that circulating blood isoprostane concentration can be a useful tool to predict the oxidative status of postmortem meat. Future work will examine the impact of this relationship on meat flavor/aroma deterioration post farm.


Assuntos
Isoprostanos/sangue , Metabolismo dos Lipídeos , Carne/normas , Ovinos/metabolismo , Ração Animal/análise , Animais , Biomarcadores/sangue , Cor , Dieta/veterinária , Feminino , Masculino , Músculos/metabolismo , Oxirredução , Estresse Oxidativo , Substâncias Reativas com Ácido Tiobarbitúrico , Vitamina E/metabolismo
20.
Meat Sci ; 132: 29-34, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28495032

RESUMO

The journal Meat Science was first published in 1976/77 and it initially comprised 4 issues per year. The first issue contained 4 papers and the first volume (4 issues) contained 27 articles, a mixture of papers and research notes. Its growth/popularity increased, and it has continued to thrive and in 2016 of the 1010 papers processed 292 were accepted. Over 90% of the papers published in the first volume were concerned with muscle biochemistry/meat properties. During the last years of the 20th century, meat products and their properties became a far larger proportion of the submissions as did those concerned with nutrition and safety. More recently there has been a resurgence of papers concerned with meat quality. Over the last 40years, the journal has reported on the major developments in meat science research and this paper will discuss both the history of the journal, and aspects of meat research as reflected in its publications. Possible future research trends are also discussed.


Assuntos
Carne , Publicações Periódicas como Assunto/história , Animais , Qualidade dos Alimentos , Tecnologia de Alimentos , História do Século XX , História do Século XXI
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