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1.
J Dairy Sci ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945256

RESUMO

Widespread genotyping has enabled the identification of putative recessive mutations that affect fertility through early embryonic fetal loss, or compromise neonate or calf viability. The use of artificial insemination in the global dairy population can rapidly spread these harmful mutations, and testing for multiple mutations can become relatively expensive if not all tests are available on the same SNP panel. However, it is possible to provide heifer and cow predicted carrier status to farmers at no additional cost if the animals are genotyped with a standard SNP panel. Additionally, for defects where the causal mutation is unknown, but a haplotype of markers has been associated with the defect, the carrier status can be predicted based on that haplotype. The aims of this study were 3-fold: 1) to determine the accuracy of imputation of putative causal mutations for recessive deleterious conditions in Australian dairy cattle, 2) to impute carrier status for known recessive deleterious conditions in all genotyped Australian Holstein, Jersey and Red breed cows, and 3) to determine the changes in carrier frequencies across time for these recessive deleterious mutations. We used the F1 statistic, combining precision and recall, to assess the accuracy of carrier status prediction. We showed that known deleterious mutations can be accurately imputed in Australian Holstein and Jersey cattle that are not directly genotyped for the causal mutation, with F1 ranging between 0.88 and 0.99. For recessive deleterious conditions not included on the standard Australian SNP panel, carrier status could be predicted using a marker haplotype, with F1 ranging from 0.91 to 0.92. Most putative causals and haplotypes were either stable with a low carrier percentage or had a declining carrier percentage. However, several recessive mutations showed a relatively high or increasing percentage, highlighting the importance of detecting carriers to reduce the number of at risk matings. Furthermore, the high carrier percentage of the recently identified Bovine Lymphocyte Intestinal Retention Defect (BLIRD) mutation emphasizes the importance of detection of novel mutations.

2.
J Dairy Sci ; 104(1): 539-549, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33131823

RESUMO

Methane is a greenhouse gas of high interest to the dairy industry, with 57% of Australia's dairy emissions attributed to enteric methane. Enteric methane emissions also constitute a loss of approximately 6.5% of ingested energy. Genetic selection offers a unique mitigation strategy to decrease the methane emissions of dairy cattle, while simultaneously improving their energy efficiency. Breeding objectives should focus on improving the overall sustainability of dairy cattle by reducing methane emissions without negatively affecting important economic traits. Common definitions for methane production, methane yield, and methane intensity are widely accepted, but there is not yet consensus for the most appropriate method to calculate residual methane production, as the different methods have not been compared. In this study, we examined 9 definitions of residual methane production. Records of individual cow methane, dry matter intake (DMI), and energy corrected milk (ECM) were obtained from 379 animals and measured over a 5-d period from 12 batches across 5 yr using the SF6 tracer method and an electronic feed recording system, respectively. The 9 methods of calculating residual methane involved genetic and phenotypic regression of methane production on a combination of DMI and ECM corrected for days in milk, parity, and experimental batch using phenotypes or direct genomic values. As direct genomic values (DGV) for DMI are not routinely evaluated in Australia at this time, DGV for FeedSaved, which is derived from DGV for residual feed intake and estimated breeding value for bodyweight, were used. Heritability estimates were calculated using univariate models, and correlations were estimated using bivariate models corrected for the fixed effects of year-batch, days in milk, and lactation number, and fitted using a genomic relationship matrix. Residual methane production candidate traits had low to moderate heritability (0.10 ± 0.09 to 0.21 ± 0.10), with residual methane production corrected for ECM being the highest. All definitions of residual methane were highly correlated phenotypically (>0.87) and genetically (>0.79) with one another and moderately to highly with other methane candidate traits (>0.59), with high standard errors. The results suggest that direct selection for a residual methane production trait would result in indirect, favorable improvement in all other methane traits. The high standard errors highlight the importance of expanding data sets by measuring more animals for their methane emissions and DMI, or through exploration of proxy traits and combining data via international collaboration.


Assuntos
Bovinos/metabolismo , Metano/metabolismo , Animais , Austrália , Peso Corporal/genética , Bovinos/genética , Indústria de Laticínios , Dieta/veterinária , Feminino , Genoma , Gases de Efeito Estufa , Lactação , Leite , Fenótipo , Gravidez , Seleção Artificial
3.
J Dairy Sci ; 103(3): 2460-2476, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31864748

RESUMO

Dairying in Australia is practiced in highly diverse climatic conditions and production systems, which means that re-ranking of genotypes could occur across environments that vary in temperature and humidity-that is, genotype-by-environment interactions (G × E) may exist. The objective of this study was to investigate G × E for heat tolerance with respect to milk production traits in Australian Holsteins. A total of 6.7 million test-day milk yield records for first, second, and third lactations from 491,562 cows and 6,410 sires that had progeny in different climatic environments were included in the analysis. The environmental gradient used was the temperature-humidity index (THI) calculated from climate data from 163 Australian public weather stations between 2003 and 2017. Data were analyzed using univariate reaction norm (RM) sire model, and the results were compared with multi-trait model (MT). The MT analysis treated test-day yields at 5th percentile (THI = 61; i.e., thermoneutral conditions), 50th percentile (THI = 67; i.e., moderate heat stress conditions), and 95th percentile (THI = 73; i.e., high heat stress conditions) of the trajectory of THI as correlated traits. A THI series of 61, 67, and 73, for example, is equivalent to average temperature and relative humidity of approximately 20°C and 45%, 25°C and 45%, and 31°C and 50%, respectively. We observed some degree of heterogeneity of additive (AG) and permanent environmental (PE) variance over the trajectory THI from RM analysis, with estimates decreasing at higher THI values more steeply for PE than for AG variance. The genetic correlations of the tests between the 5th and 95th percentiles of THI for milk, protein, and fat yield from RM were 0.88 ± 0.01 (standard error), 0.79 ± 0.01, and 0.86 ± 0.01, respectively, whereas the corresponding estimates from MT were 0.86 ± 0.02, 0.84 ± 0.03, and 0.87 ± 0.03. We observed lower genetic correlations between the 5th and 95th percentiles of THI for milk tests from recent years (i.e., 2009 and 2017) compared with earlier years (i.e., 2003 and 2008), which suggests that the level of G × E is increasing in the studied population and should be monitored especially in anticipation of future expected increase in daily average temperature and frequency of heat events. Overall, our results indicate presence of G × E at the upper extreme of the trajectory of THI, but the current extent of sire re-ranking may not justify providing separate genetic evaluations for different levels of heat stress. However, variations observed in the sire sensitivity to heat stress suggest that dairy herds in high heat load conditions could benefit more from using heat-tolerant or resilient sires.


Assuntos
Bovinos/fisiologia , Interação Gene-Ambiente , Leite/metabolismo , Animais , Austrália , Bovinos/genética , Indústria de Laticínios , Feminino , Genótipo , Resposta ao Choque Térmico , Umidade , Lactação , Modelos Estatísticos , Fenótipo , Temperatura , Termotolerância , Tempo (Meteorologia)
4.
J Dairy Sci ; 102(12): 11142-11152, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31587909

RESUMO

In this study, we estimated genetic parameters and genomic prediction accuracies of serum biomarkers of health in early-lactation dairy cows. A single serum sample was taken from 1,393 cows, located on 14 farms in southeastern Australia, within 30 d after calving. Sera were analyzed for biomarkers of energy balance (ß-hydroxybutyrate and fatty acids), macromineral status (Ca and Mg), protein nutritional status (urea and albumin), and immune status (globulins, albumin-to-globulin ratio, and haptoglobin). After editing, 47,162 SNP marker genotypes were used to estimate genomic heritabilities and breeding values (GEBV) for these traits in ASReml. Heritabilities were low for ß-hydroxybutyrate, fatty acids, Ca, Mg, and urea (0.09 ± 0.04, 0.18 ± 0.05, 0.07 ± 0.04, 0.19 ± 0.06, and 0.18 ± 0.05, respectively), and moderate for albumin, globulins, and albumin-to-globulin ratio (0.27 ± 0.06, 0.46 ± 0.06, and 0.41 ± 0.06, respectively). The heritability of haptoglobin concentration was close to 0. The magnitude of genetic correlations between traits (estimated using bivariate models) varied considerably (0.01 to 0.96), and standard errors of these correlations were high (0.02 to 0.44). Interestingly, the direction of most genetic correlations was favorable, suggesting that selecting for more optimal concentrations of one biomarker may result in more optimal concentrations of other biomarkers. Correlations between biomarker GEBV and existing breeding values for survival, somatic cell count, and daughter fertility were small to moderate (0.07 to 0.45) and favorable, whereas correlations with breeding values for milk production traits were small (≤0.15). Accuracies of GEBV were evaluated by using 5-fold cross validation, and by calculating accuracies from prediction error variances associated with the GEBV. Accuracies of GEBV predicted using 5-fold cross validation were low (0.05 to 0.27), whereas the means of individual accuracies were greater, ranging from 0.31 to 0.51. Although increasing the size of the reference population should theoretically improve accuracies, our results suggest that genomic prediction of health biomarkers may allow identification of cows that are less susceptible to diseases in early lactation.


Assuntos
Biomarcadores/sangue , Bovinos/sangue , Genômica , Indicadores Básicos de Saúde , Lactação/genética , Ácido 3-Hidroxibutírico/sangue , Animais , Cruzamento , Bovinos/genética , Ácidos Graxos/sangue , Feminino , Fertilidade , Genótipo , Fenótipo
5.
Rev Sci Tech ; 38(1): 199-212, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31564730

RESUMO

Rabies is a fatal viral disease that causes an estimated 59,000 human deaths each year. The majority of these deaths occur in developing countries in Asia. Canine rabies is endemic to Vietnam, which is, however, moving towards the disease's elimination. Many countries, such as Vietnam, have invested tremendous resources in controlling rabies, highlighting the goal of regional and global elimination of this neglected disease. In Vietnam, rabies is recognised as one of five high-priority, zoonotic diseases by the Ministry of Health and the Ministry of Agriculture and Rural Development. Investment by the government and by international partners for rabies prevention and control has played a substantial role in reducing human rabies deaths from 404 cases in 1992 to 74 cases in 2017. The catalyst for this effort was the Prime Minister's creation of the National Rabies Program in 1996, which led to increased support and resources for rabies prevention and control. Interventions carried out since then include the expansion of post-exposure prophylaxis centres throughout the country, the introduction or revision of key legislation and guidelines, and improved multisectoral One Health collaboration. In addition, support from international partners, such as the World Organisation for Animal Health (OIE), the World Health Organization (WHO), the Food and Agriculture Organization of the United Nations (FAO), and the Centers for Disease Control and Prevention (CDC), has helped to increase awareness, manage dog populations more effectively, and improve Vietnam's surveillance and diagnostic capabilities. To pursue the goal of eliminating dog-mediated rabies in Vietnam, political commitment is crucial. Resources must be made available to enforce the regulations and guidelines that will enable Vietnam to achieve greater canine rabies vaccination coverage. In this paper, the authors provide an overview of the animal and human health systems in Vietnam, as well as past, current and future directions of rabies prevention and control.


La rage est une maladie virale à l'issue mortelle faisant chaque année un nombre estimé de 59 000 victimes humaines. La plupart de ces décès surviennent dans les pays en développement d'Asie. Au Vietnam, la rage canine est endémique mais le pays poursuit activement l'objectif d'éliminer la rage de son territoire. À l'instar du Vietnam, plusieurs pays ont investi des ressources colossales pour contrôler la rage, renforçant ainsi la dimension régionale et mondiale de l'objectif d'élimination de cette maladie négligée. Au Vietnam, la rage figure parmi les cinq zoonoses hautement prioritaires prises en compte par le ministère de la Santé et le ministère de l'Agriculture et du développement rural. Les investissements consacrés à la prévention et au contrôle de la rage par le gouvernement et ses partenaires internationaux ont joué un rôle déterminant dans la réduction du nombre de décès humains dus à la rage, qui est passé de 404 cas en 1992 à 74 cas en 2017. L'élément catalyseur de cet effort a été la création en 1996 du Programme national de lutte contre la rage par le premier ministre de l'époque, ce qui a permis de renforcer les ressources et le soutien dédiés à la prévention et à la lutte contre la rage. Depuis lors, les interventions ont porté sur la création de centres de prophylaxie post-exposition sur tout le territoire, l'introduction ou la révision de la législation et des lignes directrices applicables et l'amélioration de la collaboration Une seule santé. En outre, le soutien de partenaires internationaux tels que l'Organisation mondiale de la santé animale (OIE), l'Organisation mondiale de la santé (OMS), l'Organisation des Nations Unies pour l'alimentation et l'agriculture (FAO) et les Centres pour le contrôle et la prévention des maladies (CDC, États-Unis d'Amérique) a abouti à une meilleure sensibilisation, à une gestion plus efficace des populations de chiens et à un renforcement des capacités de surveillance et de diagnostic au Vietnam. Un engagement politique fort est indispensable pour réussir à éliminer totalement la rage transmise par les chiens au Vietnam. Des ressources doivent être rendues disponibles afin de mettre en oeuvre la réglementation et les lignes directrices pertinentes et d'augmenter ainsi la couverture vaccinale de la population canine du pays. Les auteurs décrivent les systèmes de santé animale et publique du Vietnam ainsi que les orientations passées, actuelles et futures de la prévention et du contrôle de la rage dans le pays.


La rabia es una enfermedad vírica fatal, que según las estimaciones mata a 59 000 personas al año, mayoritariamente en países en desarrollo asiáticos. La rabia canina es endémica en el Vietnam, país que no obstante avanza ahora hacia la eliminación de la enfermedad. Como el Vietnam, muchos países han invertido cantidades colosales de recursos en la lucha antirrábica, subrayando con ello su compromiso con el objetivo de eliminar esta enfermedad desatendida a escala regional y mundial. El Ministerio de Salud y el Ministerio de Agricultura y Desarrollo Rural del Vietnam tienen catalogada la rabia como una de las cinco enfermedades zoonóticas que revisten máxima prioridad. Las inversiones en prevención y control de la rabia realizadas por el gobierno y por asociados internacionales han ayudado sensiblemente a reducir el número de personas muertas por la rabia, que ha pasado de 404 casos en 1992 a 74 en 2017. El catalizador de este esfuerzo fue la creación en 1996, por iniciativa del Primer Ministro, del Programa Nacional contra la Rabia, que se tradujo en un aumento del apoyo y los recursos destinados a prevenir y combatir la enfermedad. Entre otras intervenciones, desde entonces se ha multiplicado en todo el país el número de centros donde se dispensa profilaxis tras la exposición, se han promulgado o revisado leyes, decretos y directrices fundamentales y se ha mejorado la colaboración multisectorial en clave de Una sola salud. Además, el respaldo de asociados internacionales como la Organización Mundial de Sanidad Animal (OIE), la Organización Mundial de la Salud (OMS), la Organización de las Naciones Unidas para la Alimentación y la Agricultura (FAO) o los Centros para el Control y la Prevención de Enfermedades (CDC) de los Estados Unidos ha ayudado a generar una mayor conciencia del problema, a gestionar más eficazmente las poblaciones de perros y a dotar al país de mejores medios de vigilancia y diagnóstico. Para hacer realidad el objetivo de eliminar del Vietnam la rabia transmitida por perros, la voluntad política es un factor clave, pues hay que poner sobre la mesa los recursos necesarios para aplicar los reglamentos y normas que permitirán al país ampliar la cobertura de vacunación canina antirrábica. Tras trazar una panorámica de los sistemas sanitario y zoosanitario del Vietnam, los autores describen el rumbo pasado, presente y futuro de las labores de prevención y control de la rabia en el país.


Assuntos
Erradicação de Doenças , Doenças do Cão , Raiva , Animais , Erradicação de Doenças/tendências , Doenças do Cão/epidemiologia , Doenças do Cão/prevenção & controle , Cães , Humanos , Raiva/epidemiologia , Raiva/prevenção & controle , Vietnã/epidemiologia , Zoonoses/epidemiologia , Zoonoses/prevenção & controle
6.
Ann Ig ; 31(3): 291-305, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31069373

RESUMO

Since the Expanded Program on Immunization was proposed by the World Health Organization in 1981, it has been promptly adopted by Vietnam as one of the country's national priority programs. In 1986, Vietnam achieved some remarkable goals, including polio-free status and the elimination of neonatal tetanus. At the same time, however, barriers and difficulties have also emerged. This article aims to provide an overview of both achievements and barriers to the implementation of the program and proposes some solutions.


Assuntos
Vacinação/estatística & dados numéricos , Atenção à Saúde/estatística & dados numéricos , Países em Desenvolvimento/estatística & dados numéricos , Educação em Saúde , Pessoal de Saúde/educação , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Disparidades em Assistência à Saúde/estatística & dados numéricos , Humanos , Imunização , Programas de Imunização/economia , Programas de Imunização/estatística & dados numéricos , Esquemas de Imunização , Sarampo/epidemiologia , Sarampo/prevenção & controle , Morbidade/tendências , Cobertura Vacinal/estatística & dados numéricos , Recusa de Vacinação/psicologia , Recusa de Vacinação/estatística & dados numéricos , Doenças Preveníveis por Vacina/epidemiologia , Vietnã/epidemiologia
7.
J Dairy Sci ; 101(4): 3702-3713, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29454697

RESUMO

Genomic selection has led to opportunities for developing new breeding values that rely on phenotypes in dedicated reference populations of genotyped cows. In Australia, it has been applied to 2 novel traits: feed efficiency, which was released in 2015 as feed saved breeding values, and heat tolerance genomic breeding values, released for the first time in 2017. Feed saved is already included in the national breeding objective, which is focused on profitability and designed to be in line with farmer preferences. Our future focus is on traits associated with animal health, either directly or in combination with predictor traits, such as mid-infrared spectral data and, into the future, automated data capture. Although it is common for many evaluated traits to have genomic reliabilities ranging between 60 and 75%, many new, genomic information-only traits are likely to have reliabilities of less than 50%. Pooling of phenotype data internationally and investing in maintenance of reference populations is one option to increase the reliability of these traits; the other is to apply improved genomic prediction methods. For example, advances in the use of sequence data, in addition to gene expression studies, can lead to improved persistence of genomic breeding values across breeds and generations and potentially lead to greater reliabilities. Lower genomic reliabilities of novel traits could reduce the overall index reliability. However, provided these traits contribute to the overall breeding objective (e.g., profit), they are worth including. Bull selection tools and personalized genetic trends are already available, but increased access to economic and automatic capture farm data may see even better use of data to improve farm management and selection decisions.


Assuntos
Cruzamento , Bovinos , Seleção Genética , Animais , Austrália , Indústria de Laticínios , Feminino , Genômica/métodos , Genótipo , Masculino , Fenótipo
8.
Eur J Dent Educ ; 22(3): e594-e601, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29717531

RESUMO

INTRODUCTION: This study explored stress predictors and the role of instructional methods and institutional differences in perceived stress levels amongst students at two Asian dental schools. MATERIALS AND METHODS: An anonymous questionnaire was distributed to undergraduate dental students at Tokyo Medical and Dental University (TMDU), Japan and the University of Medicine and Pharmacy (UMP), Hochiminh City, Vietnam in 2016. Data concerning the students' demographic information and grades, and responses to the Perceived Stress Scale (PSS) and Dental Environment Stress questionnaire (DES) were collected. The questionnaires were prepared in English and translated into Japanese and Vietnamese following a forward-backward translation process. RESULTS: Altogether 684 students answered the questionnaire with a response rate of 97% for TMDU and 89% for UMP. The mean DES score of UMP students was significantly higher than TMDU (P < .001). TMDU students with dentistry as their first programme choice had significantly lower PSS and DES scores in several categories than other TMDU students, whilst UMP clinical students reported higher stress scores in several areas than UMP preclinical students. CONCLUSION: Having dentistry as their first choice of educational programme was a significant stress predictor for Japanese students whilst the clinical practicum was a significant stress predictor for Vietnamese students. Previous academic performance was not a significant stress predictor for students at either dental school. Dental students of an integrated, active-learning curriculum reported lower stress levels than students of a traditional, discipline-based curriculum.


Assuntos
Currículo , Educação em Odontologia , Faculdades de Odontologia , Estresse Psicológico , Estudantes de Odontologia/psicologia , Ensino , Educação em Odontologia/métodos , Feminino , Previsões , Humanos , Japão , Masculino , Inquéritos e Questionários , Vietnã
9.
Arch Virol ; 161(2): 479-82, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26586330

RESUMO

An apparently single rotavirus A strain possessing a genotype constellation of G8-P[8]-I2-R2-C2-M2-A2-N2-T2-E2-H2 abruptly emerged, caused diarrhoea in children requiring hospitalisation, and increased to reach 27 % of strains detected during the first half of 2015 in Vietnam.


Assuntos
Surtos de Doenças , Genótipo , Recombinação Genética , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Rotavirus/classificação , Rotavirus/isolamento & purificação , Análise por Conglomerados , Gastroenterite/epidemiologia , Gastroenterite/virologia , Humanos , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Rotavirus/genética , Análise de Sequência de DNA , Homologia de Sequência , Vietnã/epidemiologia
10.
Eur Rev Med Pharmacol Sci ; 28(5): 1857-1863, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38497868

RESUMO

OBJECTIVE: The clinical frailty scale (CFS) evaluates the level of frailty based on clinical examination, comorbidities, and functional and activity levels of older patients. However, there are many difficulties for internists in evaluating frailty with this scale. Therefore, simplifying the CFS with good design and application is required for better treatment outcomes. Our study was conducted to design and evaluate the correlation of a simplified clinical frailty scale (sCFS) with CFS in older patients. PATIENTS AND METHODS: We undertook a cross-sectional analysis involving 279 older patients, which comprised two steps. Step 1 involves the implementation of sCFS, a protocol that has been endorsed by the Geriatrics Professional Council (GPC). Step 2 entails the enrollment of older patients for frailty assessment using sCFS, comparing it with CFS. RESULTS: The study was conducted on 279 older patients; the average age was 75.7 ± 8.4 (years old), and men accounted for 34.8%. There was a high correlation between the sCFS and CFS (Pearson's r = 0.996; p < 0.001). The similarity of the sCFS to the CFS was very high, with Kappa coefficient = 0.984 (p < 0.001). Compared with the CFS, the sCFS had a Youden index of 98% with 100% sensitivity and 98% specificity assessed through the receiver operating characteristic (ROC) with the CFS threshold of 5. CONCLUSIONS: The sCFS can be used to assess frailty with high sensitivity and specificity.


Assuntos
Fragilidade , Geriatria , Masculino , Humanos , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Fragilidade/diagnóstico , Pacientes , Exame Físico , Fator de Células-Tronco
11.
J Fish Biol ; 80(3): 651-68, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22380559

RESUMO

This study investigated population genetic structure and diversity of mud carp Cirrhinus molitorella, a species widely used in aquaculture and culture-based fisheries in China and Mekong River riparian countries. Seven newly developed and one published microsatellite DNA markers were used to analyse samples from six wild locations, four hatchery broodstocks and one farmed site from the Mekong, Red and Pearl Rivers. Significant genetic structure was detected in C. molitorella, with isolation-by-distance being a strong force in the Mekong. Pair-wise F(ST) , Fisher's exact tests for population differentiation, permutation tests and individual-based structure analysis all support the recognition of a sample originating from Toul Krasaing Lake (Cambodia) and one between Kratie and Stung Treng (Cambodia) as distinct from the remainder of the sampled range. Samples from the main upper Mekong and the Nam Khan River were significantly differentiated, but on a time scale inferred to be short (i.e. by genetic drift, not sufficient for evolution of new microsatellite alleles). The Mekong stock of C. molitorella was strongly differentiated from those from the Red and Pearl Rivers, inferred to be on an evolutionary time scale. Finer-scale sampling is warranted to further improve the understanding of genetic interactions among fish from the Mekong and its tributaries. Detailed studies on the ecology of C. molitorella (e.g. migration pathways and preferred spawning habitats) would provide useful information to explain the patterns of genetic structure detected here, and deepen insights about evolutionary distinctiveness of the population units.


Assuntos
Cipriniformes/genética , Pesqueiros , Rios , Animais , Camboja , Conservação dos Recursos Naturais , Marcadores Genéticos , Variação Genética , Desequilíbrio de Ligação , Repetições de Microssatélites , Dinâmica Populacional
12.
Sci Rep ; 12(1): 18304, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36316344

RESUMO

Unexpectedly, granular materials can fail, the structure even destroyed, spontaneously in simple isotropic compression with stick-slip-like frictional behaviour. This extreme behaviour is conceptually impossible for saturated two-phase assembly in classical granular physics. Furthermore, the triggering mechanisms of these laboratory events remain mysterious, as in natural earthquakes. Here, we report a new interpretation of these failures in under-explored isotropic compression using the time-frequency analysis of Cauchy continuous wavelet transform of acoustic emissions and multiphysics numerical simulations. Wavelet transformation techniques can give insights into the temporal evolution of the state of granular materials en route to failure and offer a plausible explanation of the distinctive hearing sound of the stick-slip phenomenon. We also extend the traditional statistical seismic Gutenberg-Richter power-law behaviour for hypothetical biggest earthquakes based on the mechanisms of stick-slip frictional instability, using very large artificial isotropic labquakes and the ultimate unpredictable liquefaction failure.

13.
J Anim Breed Genet ; 128(6): 482-90, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22059582

RESUMO

This study aimed to estimate the heritabilities of three economically important traits (total weight, shell shape and meat yield) in Australian blue mussels. The estimates were derived using a pedigree reconstructed from a suite of both published and newly developed microsatellite markers. A total of 135 microsatellite loci were tested, of which 10 loci produced consistent PCR amplification and reliable results across all samples (74 full-sibling families including 74 pairs of parents and 2536 offspring). Lack of polymorphism at the non-repetitive region of the adhesive protein gene confirmed that the broodstock were derived from a single species. A total of 1538 progenies (62.5%) could be assigned to single parent pairs, and the remainder were assigned to two families or more, so were discarded from further analysis. Heritabilities for total weight, shell shape and meat yield were low (0.051 ± 0.027, 0.085 ± 0.038 and 0.049 ± 0.028, respectively) but reflected large environmental variation rather than limited genetic variation, suggesting a family-based breeding programme could improve these traits. The genetic correlation between weight and meat yield, expressed as percentage of total mussel which was not shell, was negative, while the genetic correlation between meat yield and shell shape was weakly positive.


Assuntos
Repetições de Microssatélites/genética , Mytilus/anatomia & histologia , Mytilus/genética , Linhagem , Exoesqueleto/anatomia & histologia , Animais , Peso Corporal/genética , Feminino , Padrões de Herança , Masculino , Carne , Mytilus/crescimento & desenvolvimento , Estatística como Assunto
14.
Sci Rep ; 11(1): 2902, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536583

RESUMO

We report high-temporal-resolution observations of the spontaneous instability of model granular materials under isotropic and triaxial compression in fully drained conditions during laboratory tests representative of earthquakes. Unlike in natural granular materials, in the model granular materials, during the first stage of the tests, i.e., isotropic compression, a series of local collapses of various amplitudes occurs under random triggering cell pressures. During the second stage, i.e., shearing under triaxial compression, the model granular samples exhibit very large quasiperiodic stick-slip motions at random deviatoric triggering stresses. These motions are responsible for very large stress drops that are described by power laws and are accurate over more than 3 decades in logarithmic space. Then, we identify the quasideterministic nature of these stick-slip events, assuming that they are fully controlled by the cell pressure and solid fraction. Finally, we discuss the potential mechanisms that could explain these intriguing behaviors and the possible links with natural earthquakes.

15.
Sci Rep ; 10(1): 19181, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154392

RESUMO

Heat stress in dairy cattle leads to reduction in feed intake and milk production as well as the induction of many physiological stress responses. The genes implicated in the response to heat stress in vivo are not well characterised. With the aim of identifying such genes, an experiment was conducted to perform differential gene expression in peripheral white blood cells and milk somatic cells in vivo in 6 Holstein Friesian cows in thermoneutral conditions and in 6 Holstein Friesian cows exposed to a short-term moderate heat challenge. RNA sequences from peripheral white blood cells and milk somatic cells were used to quantify full transcriptome gene expression. Genes commonly differentially expressed (DE) in both the peripheral white blood cells and in milk somatic cells were associated with the cellular stress response, apoptosis, oxidative stress and glucose metabolism. Genes DE in peripheral white blood cells of cows exposed to the heat challenge compared to the thermoneutral control were related to inflammation, lipid metabolism, carbohydrate metabolism and the cardiovascular system. Genes DE in milk somatic cells compared to the thermoneutral control were involved in the response to stress, thermoregulation and vasodilation. These findings provide new insights into the cellular adaptations induced during the response to short term moderate heat stress in dairy cattle and identify potential candidate genes (BDKRB1 and SNORA19) for future research.


Assuntos
Expressão Gênica , Resposta ao Choque Térmico/genética , Leucócitos/metabolismo , Leite/citologia , Animais , Bovinos , Feminino , Temperatura Alta , Leite/metabolismo , Transcriptoma
16.
Biomed Res Int ; 2020: 9850351, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33274234

RESUMO

BACKGROUND: Scarce information exists about immunity to hand, foot, and mouth disease (HFMD) among household contacts of index cases in Vietnam and what that means for reducing ongoing HFMD transmission in the community. METHODS: We analyzed neutralizing antibodies (NT) and the incidence of enterovirus (EVs) infection among household contacts of index cases in a province where HFMD remains endemic. Throat swab and 2 mL blood samples from household contacts were collected at enrollment, during and after 2 weeks follow-up. RESULTS: The incidence of EV-A71 infection among household contacts was 40/84 (47.6%, 95% Cl: 36.9-58.3%), compared with 106/336 (31.5%, 95% Cl: 26.6-36.5%) for CV-A6 and 36/107 (33.6%, 95% Cl: 24.7-42.6%) for CV-A16. The incidence of CV-A6 infection was fairly constant across ages; in contrast, CV-A71 and CV-A16 had some variation across ages. At baseline, higher geometric mean titer (GMT) of EV-A71, CV-A6, and CV-A16 antibody titers was found for 25-34-year groups (range 216.3 to 305.0) compared to the other age groups. There was a statistically significant difference in GMT values of CV-A6 and CV-A16 between those who had an infection or did not have infection among households with an index case of these serotypes. CONCLUSIONS: Our results indicated that adults were becoming infected with HFMD and could be contributing to the transmission. There is, therefore, a need for considering the household setting as an additional target for intervention programs for HFMD.


Assuntos
Infecções por Coxsackievirus/epidemiologia , Infecções por Coxsackievirus/virologia , Enterovirus Humano A/fisiologia , Infecções por Enterovirus/epidemiologia , Infecções por Enterovirus/virologia , Enterovirus/fisiologia , Características da Família , Adolescente , Adulto , Fatores Etários , Anticorpos Neutralizantes , Criança , Pré-Escolar , Infecções por Coxsackievirus/imunologia , Enterovirus/imunologia , Enterovirus Humano A/imunologia , Infecções por Enterovirus/imunologia , Seguimentos , Humanos , Incidência , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Sorogrupo , Vietnã/epidemiologia , Carga Viral , Adulto Jovem
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