Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 102
Filtrar
1.
Vet J ; 298-299: 106015, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37479055

RESUMO

The objective of this observational study was to quantify associations between Mycobacterium avium subspecies paratuberculosis (MAP) antibody status and a variety of fertility outcomes, in UK dairy cattle. Longitudinal milk recording, fertility and MAP antibody enzyme-linked immunosorbent assay (ELISA) milk test data were collated retrospectively from 121,762 lactations in 78 herds. Datasets were structured into appropriate units to suit outcomes and enable temporal association between current and future MAP status, and fertility measures. Current MAP status was categorised according to most recent status within 180 days, with time-related future MAP status assigned based on MAP antibody ELISA milk test data for each cow. Multilevel multivariable logistic regression models were used to evaluate associations between MAP status and 21-day pregnancy and submission rate and conception risk. Posterior predictions and cross-validation techniques were used to assess model fit and check model building assumptions. A negative association was found between risk of insemination (Odds Ratio [OR], 0.78; 95% Credible Interval [CI], 0.66-0.92) and conception occurring (OR, 0.65; CI, 0.5-0.84) and transition from negative to non-negative MAP test status in the next 30-90 days. A positive association was observed between risk of insemination (OR, 1.34; CI, 1.16-1.52) and conception occurring (OR, 1.26; CI, 1.11-1.43) and transition from negative to non-negative MAP test status in the next 90-180 days. Current positive MAP test status was negatively and positively associated with insemination (OR, 0.59; CI, 0.49-0.70) and conception risk (OR, 1.12; CI, 0.96-1.30), respectively. Herd managers will have had access to test results, declaring cows with past recent or multiple positive MAP antibody ELISA results not to be bred, negatively influencing insemination risk. Overall, these results demonstrate the temporal association between a positive MAP antibody ELISA result and dairy cow fertility outcomes, with particular variability prior to a positive MAP antibody ELISA result.


Assuntos
Doenças dos Bovinos , Mycobacterium avium subsp. paratuberculosis , Paratuberculose , Animais , Bovinos , Feminino , Gravidez , Anticorpos Antibacterianos/análise , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Fezes/microbiologia , Fertilidade , Leite/microbiologia , Paratuberculose/epidemiologia , Paratuberculose/microbiologia , Estudos Retrospectivos , Reino Unido/epidemiologia
2.
ACS Omega ; 6(35): 22717-22725, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34514243

RESUMO

A method for the rapid assessment of metallic impurities in carbon nanotubes (CNTs) by pin-cell source geometry glow discharge mass spectrometry (GDMS) is presented. Pins were prepared by pressing CNT powder onto an indium substrate. GDMS analysis was performed using high-carbon-content nanotube and coal-certified reference materials for calibration purposes. This approach enables the calibrated measurement of 41 elemental impurities in CNTs. The method was validated by the analysis of NIST SRM 2483 single-wall CNTs (raw soot) with good agreement with the certified values. The proposed measurement approach could also be applied not only for CNTs but also for the assessment of precursor materials used in the synthesis of CNTs and for quality control during the entire manufacturing process. The ability to assess the presence of all metallic impurities in a simple, reliable, high-throughput manner will allow the industry to real-time monitor any changes in the product process, access its toxicity, and environmental impact. As sample preparation is maintained to a minimum, this allows the determination of metallic impurities at concentration levels that are usually not attainable by most techniques.

3.
J Dairy Sci ; 104(8): 9063-9081, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33934854

RESUMO

Selective use of antibiotic dry cow treatment can be implemented at the cow or quarter level, with the latter having the potential to further reduce antibiotic use. Our objective was to compare these 2 approaches in 6 herds in the United Kingdom in which environmental mastitis predominated. Eight hundred seven cows were enrolled and categorized as having a high cell count (n = 401) or low cell count (n = 406) in the last 3 mo of lactation and clinical mastitis history. All quarters of all enrolled cows received an internal teat sealant. Within each category, cows were randomly allocated to 1 of 3 groups; in one group antibiotic treatment was allocated at cow level (i.e., all 4 quarters received antibiotic), whereas in the 2 remaining groups antibiotic treatment was allocated at quarter level, based on California Mastitis Test (CMT) findings. Two different thresholds, score 1 and 2, were used to determine likely infection status. Quarter milk samples were collected at dry off and postcalving for bacteriological culture and somatic cell count (SCC). Cows were monitored for clinical mastitis from dry off until 100 d in milk. Cow level SCC and milk yield data were collated from farm records. Within each category, the 2 quarter level treatment groups were compared with cow level treatment at dry off. Leaving quarters untreated with intramammary antibiotic in cows in the high cell count group, with a CMT <2 or <1, reduced antibiotic use by 55% and 31%, respectively, and resulted in no difference in the odds of being infected with any pathogen postcalving, but was associated with a higher SCC at the first test day. Intramammary antibiotic treatment of quarters with a CMT ≥1 in cows in the low cell count category at dry off was not associated with any reduction in the odds of being infected with a major pathogen postcalving but was associated with a decrease in the odds of being infected with a minor mastitis pathogen postcalving. The use of antibiotics in quarters of cows categorized as low cell count at dry off, increased the proportion of quarters treated with antibiotic from 0% at cow level to 31% (CMT ≥ 1) and 12% (CMT ≥ 2) at quarter level, only resulting in a reduction in SCC of around 20,000 cells/mL at the first test day, if all quarters with CMT score ≥1 were treated with antibiotic. No differences in clinical mastitis incidence and milk yield in the first 100 d in milk were detected between any of the treatment groups. These study findings support selective quarter level dry off treatment only in cows with cow level SCC >200,000 cells/mL at dry off.


Assuntos
Doenças dos Bovinos , Mastite Bovina , Mastite , Animais , Antibacterianos/uso terapêutico , California , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Contagem de Células/veterinária , Feminino , Lactação , Glândulas Mamárias Animais , Mastite/tratamento farmacológico , Mastite/veterinária , Mastite Bovina/tratamento farmacológico , Leite , Reino Unido
4.
Clin Radiol ; 76(2): 129-134, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33309335

RESUMO

AIM: To determine the proportion of renal cancers for which incidental detection was the route to diagnosis, the characteristics of tumours identified in this way, and the frequency with which opportunities to make this diagnosis were missed. MATERIALS AND METHODS: Consecutive patients with renal cancers treated at Royal Cornwall Hospitals NHS Trust (April 2011 and July 2018 inclusive) were identified from the Trust's cancer registry database, and a retrospective review of the imaging and electronic case notes was undertaken. Mann-Whitney U-tests for comparison of patient age and tumour size at diagnosis, and chi-squared tests for comparing cell type distribution and grade were performed. Logistic regression was then used to identify the characteristics of patients in whom a renal tumour was missed initially. RESULTS: Of 327 patients, 194 (63%) presented incidentally, and 133 (37%) symptomatically. Incidentally detected cancers were found in younger patients, (median of 65 years versus 69 p=0.01) and were smaller at presentation (median of 5.5 versus 7.2 cm, p<0.00001). Thirty-six different reporters missed opportunities to diagnose renal cancer in 50 (16%) patients on 78 occasions, 28 lesions (35%) being missed more than once. Thirty were imaged incompletely; four were visible only on a single image and three on a scout view at magnetic resonance imaging. CONCLUSION: The commonest route to diagnosis of renal cancer is by incidental detection of a mass. In 16% of patients in whom renal cancer is diagnosed, there is at least one prior examination on which the lesion is visible at an earlier date. The clinical impact of these missed diagnostic opportunities remains uncertain.


Assuntos
Erros de Diagnóstico/estatística & dados numéricos , Diagnóstico por Imagem/métodos , Achados Incidentais , Neoplasias Renais/diagnóstico por imagem , Idoso , Feminino , Humanos , Rim/diagnóstico por imagem , Masculino , Sistema de Registros/estatística & dados numéricos , Estudos Retrospectivos
5.
Psychol Med ; 50(1): 125-132, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30646966

RESUMO

BACKGROUND: Bipolar disorder (BD) is associated with attentional and processing abnormalities. Such abnormalities are also seen in healthy subjects with sleep disruption. We hypothesised cognitive abnormalities in BD patients would be worse in those with objectively verified sleep abnormalities. METHODS: Forty-six BD patients and 42 controls had comprehensive sleep/circadian rhythm assessment over 21 days alongside mood questionnaires. Cognitive function was assessed with a range of tasks including Psychomotor Vigilance Test (PVT), Attention Network Task (ANT) and Digit Symbol Substitution Test (DSST). BD participants with normal and abnormal sleep were compared with age- and sex-matched controls. RESULTS: BD patients had longer response times and made more lapses (responses >500 ms) than controls on the PVT (both p < 0.001). However, patients with normal sleep patterns did not differ from controls while those with sleep abnormalities did (p < 0.001). An identical pattern of effects were seen with the ANT response times, with the abnormality in bipolar abnormal sleepers related to the executive attentional network. Similarly, patients made fewer correct responses on the DSST compared with the controls (p < 0.001). Bipolar normal sleepers did not differ while those with abnormal sleep did (p < 0.001). All these differences were seen in bipolar abnormal sleepers who were euthymic (p < 0.01) and across the main abnormal sleep phenotypes. CONCLUSIONS: We confirm impairment in attention and processing speed in BD. Rather than sleep abnormalities exacerbating such dysfunction, the impairments were confined to bipolar abnormal sleepers, consistent with sleep disturbance being the main driver of cognitive dysfunction.


Assuntos
Transtorno Bipolar/psicologia , Disfunção Cognitiva/psicologia , Transtornos do Sono-Vigília/psicologia , Sono , Adulto , Transtorno Bipolar/complicações , Estudos de Casos e Controles , Disfunção Cognitiva/complicações , Inglaterra , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Transtornos do Sono-Vigília/complicações
6.
Vet Parasitol ; 256: 1-8, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29887023

RESUMO

It is agreed that exposure of adult dairy cattle to helminths on pasture can negatively affect production performances as milking herd. Young animals, especially replacement heifers, represent the future of a dairy farm and are among the most vulnerable to helminth infections in a dairy herd. For this reason, dairy farmers tend to frequently treat heifers against helminths, although the impact of helminths on heifers' production performances is still poorly understood. Using different epidemiological and serological tools, this study examines the relationship between heifer exposure to helminths on pasture and production performances over time. During a one-year period, 1,454 individual milk samples were collected from first-lactation heifers in England and tested for Ostertagia ostertagi (O. ostertagi) antibodies. After controlling for other confounders, increasing milk antibody levels against O. ostertagi were significantly associated with decreased milk yield at sampling but not at day 305 of heifer lactation. We did not observe any relationship between milk antibody levels against O. ostertagi in heifers and yields in fat and protein. However, heifers with a high level of milk antibodies against O. ostertagi were more likely to produce dead calf at first calving and present a delay in second calving. Moreover, these heifers had significantly higher levels of milk antibodies against Mycobacterium paratuberculosis (M. paratuberculosis) during their first lactation and were more likely to die before the end of the study. We argue that epidemiological approaches can be useful but must be complemented by other methodologies to better understand the impact of helminth infections in dairy heifers. In order to address the complex dynamics of helminth infections in dairy cattle production we require more comprehensive approaches that include triangulation between data sources and interdisciplinary studies.


Assuntos
Anticorpos Anti-Helmínticos/análise , Lactação/fisiologia , Leite/imunologia , Ostertagia/imunologia , Animais , Bovinos , Feminino , Helmintíase Animal/imunologia , Helmintíase Animal/mortalidade , Leite/química
7.
J Dairy Sci ; 101(1): 537-546, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29128225

RESUMO

The gastrointestinal nematode Ostertagia ostertagi is an important cause of lost production, health, and welfare in cattle. Detailed records were obtained over a 5-yr period (2010-2015) by questionnaires and qualitative interviews to investigate the practices adopted by dairy farmers to control cattle helminth infections and the factors associated with heifer exposure to O. ostertagi on pasture. In total, 1,454 heifers' individual milk samples were collected over a 1-yr period (2014-2015) in 43 dairy farms in England and tested for O. ostertagi antibody by ELISA. Multilevel linear regression models were used to investigate the association between individual milk optical density ratio (ODR) against O. ostertagi and heifer management from birth to time of sampling. Farm and heifer median ODR against O. ostertagi were 0.98 (interquartile range = 0.76-1.02) and 0.64 (interquartile range = 0.42-0.84), respectively. The majority of heifers (88%) received an anthelmintic treatment before sampling in this study. After controlling for the effect of anthelmintic treatments, heifer individual milk ODR against O. ostertagi significantly increased with high stocking rate at first grazing and co-grazing with adult cows before calving. Conversely, heifer individual milk ODR against O. ostertagi significantly decreased when heifers had co-grazed with sheep and pasture grass had frequently been mowed. Overall, these results provide evidence to support targeting grazing management toward limiting the use of anthelmintics in dairy young stock to enable sustainable control of cattle helminth infections in England. However, to be accepted and adopted by farmers, these best practices would need to take into account farmers' perspectives and contextual challenges.


Assuntos
Anti-Helmínticos/uso terapêutico , Anticorpos Anti-Helmínticos/análise , Leite/parasitologia , Ostertagia/imunologia , Ostertagíase/veterinária , Animais , Bovinos , Inglaterra , Ensaio de Imunoadsorção Enzimática/veterinária , Fazendas , Feminino , Trato Gastrointestinal/parasitologia , Lactação , Modelos Lineares , Estudos Longitudinais , Ostertagia/isolamento & purificação , Ostertagíase/tratamento farmacológico , Ostertagíase/epidemiologia , Ostertagíase/parasitologia
8.
Prev Vet Med ; 145: 91-99, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28903881

RESUMO

The objective of this study was to use probabilistic sensitivity analysis to evaluate the cost-effectiveness of using an on-farm culture (OFC) approach to the treatment of clinical mastitis in dairy cows and compare this to a 'standard' treatment approach. A specific aim was to identify the herd circumstances under which an OFC approach would be most likely to be cost-effective. A stochastic Monte Carlo model was developed to simulate 5000 cases of clinical mastitis at the cow level and to calculate the associated costs simultaneously when treated according to 2 different treatment protocols; i) a 'conventional' approach (3 tubes of intramammary antibiotic) and ii) an OFC programme, whereby cows are treated according to the results of OFC. Model parameters were taken from recent peer reviewed literature on the use of OFC prior to treatment of clinical mastitis. Spearman rank correlation coefficients were used to evaluate the relationships between model input values and the estimated difference in cost between the standard and OFC treatment protocols. The simulation analyses revealed that both the difference in the bacteriological cure rate due to a delay in treatment when using OFC and the proportion of Gram-positive cases that occur on a dairy unit would have a fundamental impact on whether OFC would be cost-effective. The results of this study illustrated that an OFC approach for the treatment of clinical mastitis would probably not be cost-effective in many circumstances, in particular, not those in which Gram-positive pathogens were responsible for more than 20% of all clinical cases. The results highlight an ethical dilemma surrounding reduced use of antimicrobials for clinical mastitis since it may be associated with financial losses and poorer cow welfare in many instances.


Assuntos
Antibacterianos/uso terapêutico , Análise Custo-Benefício , Mastite Bovina/diagnóstico , Mastite Bovina/tratamento farmacológico , Animais , Técnicas Bacteriológicas , Bovinos , Indústria de Laticínios/métodos , Fazendas , Feminino , Mastite Bovina/economia , Leite , Resultado do Tratamento
9.
Psychol Med ; 47(9): 1678-1689, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28173893

RESUMO

BACKGROUND: Subjective reports of insomnia and hypersomnia are common in bipolar disorder (BD). It is unclear to what extent these relate to underlying circadian rhythm disturbance (CRD). In this study we aimed to objectively assess sleep and circadian rhythm in a cohort of patients with BD compared to matched controls. METHOD: Forty-six patients with BD and 42 controls had comprehensive sleep/circadian rhythm assessment with respiratory sleep studies, prolonged accelerometry over 3 weeks, sleep questionnaires and diaries, melatonin levels, alongside mood, psychosocial functioning and quality of life (QoL) questionnaires. RESULTS: Twenty-three (50%) patients with BD had abnormal sleep, of whom 12 (52%) had CRD and 29% had obstructive sleep apnoea. Patients with abnormal sleep had lower 24-h melatonin secretion compared to controls and patients with normal sleep. Abnormal sleep/CRD in BD was associated with impaired functioning and worse QoL. CONCLUSIONS: BD is associated with high rates of abnormal sleep and CRD. The association between these disorders, mood and functioning, and the direction of causality, warrants further investigation.


Assuntos
Transtorno Bipolar , Ritmo Circadiano/fisiologia , Melatonina/metabolismo , Transtornos do Sono-Vigília , Adulto , Transtorno Bipolar/epidemiologia , Transtorno Bipolar/metabolismo , Transtorno Bipolar/fisiopatologia , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Apneia Obstrutiva do Sono/epidemiologia , Apneia Obstrutiva do Sono/metabolismo , Apneia Obstrutiva do Sono/fisiopatologia , Transtornos do Sono do Ritmo Circadiano/epidemiologia , Transtornos do Sono do Ritmo Circadiano/metabolismo , Transtornos do Sono do Ritmo Circadiano/fisiopatologia , Transtornos do Sono-Vigília/epidemiologia , Transtornos do Sono-Vigília/metabolismo , Transtornos do Sono-Vigília/fisiopatologia , Adulto Jovem
10.
Prev Vet Med ; 133: 64-72, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27720028

RESUMO

Importance of the dry period with respect to mastitis control is now well established although the precise interventions that reduce the risk of acquiring intramammary infections during this time are not clearly understood. There are very few intervention studies that have measured the clinical efficacy of specific mastitis interventions within a cost-effectiveness framework so there remains a large degree of uncertainty about the impact of a specific intervention and its costeffectiveness. The aim of this study was to use a Bayesian framework to investigate the cost-effectiveness of mastitis controls during the dry period. Data were assimilated from 77 UK dairy farms that participated in a British national mastitis control programme during 2009-2012 in which the majority of intramammary infections were acquired during the dry period. The data consisted of clinical mastitis (CM) and somatic cell count (SCC) records, herd management practices and details of interventions that were implemented by the farmer as part of the control plan. The outcomes used to measure the effectiveness of the interventions were i) changes in the incidence rate of clinical mastitis during the first 30days after calving and ii) the rate at which cows gained new infections during the dry period (measured by SCC changes across the dry period from <200,000cells/ml to >200,000cells/ml). A Bayesian one-step microsimulation model was constructed such that posterior predictions from the model incorporated uncertainty in all parameters. The incremental net benefit was calculated across 10,000 Markov chain Monte Carlo iterations, to estimate the cost-benefit (and associated uncertainty) of each mastitis intervention. Interventions identified as being cost-effective in most circumstances included selecting dry-cow therapy at the cow level, dry-cow rations formulated by a qualified nutritionist, use of individual calving pens, first milking cows within 24h of calving and spreading bedding evenly in dry-cow yards. The results of this study highlighted the efficacy of specific mastitis interventions in UK conditions which, when incorporated into a costeffectiveness framework, can be used to optimize decision making in mastitis control. This intervention study provides an example of how an intuitive and clinically useful Bayesian approach can be used to form the basis of an on-farm decision support tool.


Assuntos
Simulação por Computador , Análise Custo-Benefício , Tomada de Decisões , Lactação , Mastite Bovina/economia , Mastite Bovina/prevenção & controle , Animais , Teorema de Bayes , Bovinos , Feminino , Modelos Estatísticos , Reino Unido
11.
J Dairy Sci ; 99(9): 6855-6873, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27372587

RESUMO

Metabolic disorders are disturbances to one or more of the metabolic processes in dairy cattle. Dysfunction of any of these processes is associated with the manifestation of metabolic diseases or disorders. In this review, data recording, incidences, genetic parameters, predictors, and status of genetic evaluations were examined for (1) ketosis, (2) displaced abomasum, (3) milk fever, and (4) tetany, as these are the most prevalent metabolic diseases where published genetic parameters are available. The reported incidences of clinical cases of metabolic disorders are generally low (less than 10% of cows are recorded as having a metabolic disease per herd per year or parity/lactation). Heritability estimates are also low and are typically less than 5%. Genetic correlations between metabolic traits are mainly positive, indicating that selection to improve one of these diseases is likely to have a positive effect on the others. Furthermore, there may also be opportunities to select for general disease resistance in terms of metabolic stability. Although there is inconsistency in published genetic correlation estimates between milk yield and metabolic traits, selection for milk yield may be expected to lead to a deterioration in metabolic disorders. Under-recording and difficulty in diagnosing subclinical cases are among the reasons why interest is growing in using easily measurable predictors of metabolic diseases, either recorded on-farm by using sensors and milk tests or off-farm using data collected from routine milk recording. Some countries have already initiated genetic evaluations of metabolic disease traits and currently most of these use clinical observations of disease. However, there are opportunities to use clinical diseases in addition to predictor traits and genomic information to strengthen genetic evaluations for metabolic health in the future.


Assuntos
Cruzamento , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/genética , Doenças Metabólicas/veterinária , Paresia Puerperal/epidemiologia , Animais , Bovinos , Feminino , Incidência , Cetose/epidemiologia , Cetose/genética , Cetose/veterinária , Lactação , Doenças Metabólicas/epidemiologia , Doenças Metabólicas/genética , Leite/metabolismo , Paridade , Paresia Puerperal/genética , Gravidez
12.
J Dairy Sci ; 99(7): 5586-5595, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27108166

RESUMO

The dry period is very important for mammary gland health, with the aim not only to cure existing intramammary infections (IMI) but also to prevent new IMI. Although it is known that the dry period is an important time for optimizing udder health, the probability that individual cows will succumb to a new IMI or, if infected, will fail to cure an IMI is not well established. The aim of this study was to investigate whether lifetime cow data, available through routine on-farm milk recording, could be used to predict changes in IMI status across the dry period for individual cows that were (1) deemed high somatic cell count (SCC; >199,000 cells/mL) or (2) low SCC (<200,000 cells/mL) at the last test day before drying off. Milk recording data collected between September 1994 and July 2014 from 114 herds in the United Kingdom were used. Two 2-level random effects models were built and both cure and new IMI were used as outcome variables in separate models. Cows with a smaller proportion of test days with a high SCC in the lactation before drying off, a smaller proportion of test days recording a high SCC in the lactation before the current lactation, of lower parity, producing less milk before drying off, of lower days in milk at drying off, and of lower SCC just before drying off were more likely to cure across the dry period. Dry period length had no effect on the likelihood of cure. Individual cows with a smaller proportion of test days recording a high SCC in the lactation before the current, of lower parity, of lower milk production at drying off, and fewer days in milk at drying off were less likely to develop a new IMI. Dry period length was found to have no effect on the probability of new IMI. Model predictions showed that a high level of discrimination was possible between cows with a high and low risk of both cures and new infections across the dry period.


Assuntos
Lactação , Mastite Bovina/prevenção & controle , Animais , Bovinos , Contagem de Células/veterinária , Feminino , Glândulas Mamárias Animais , Mastite Bovina/epidemiologia , Leite
13.
Vet Rec ; 178(18): 449, 2016 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-26966249

RESUMO

The objectives of this study were to report performance and management data taken from a sample of UK dairy farms that have participated in the Agriculture and Horticulture Development Board Dairy Mastitis Control Plan (DMCP) and to identify important mastitis prevention practices that are not currently widely implemented. A total of 234 UK dairy herds were included in the study from which farm management and udder health data were collected. Herds were grouped according to their mastitis epidemiology and could be classed as (i) environmental dry period (EDP) (i.e. environmental pathogen with majority of infections being acquired during the dry period), (ii) environmental lactation (EL), (iii) contagious dry period (CDP) or (iv) contagious lactation (CL). The results of this study showed that many mastitis-related management practices that are generally considered to be important were not widely performed. A better understanding of those practices not widely adopted by UK dairy farmers at present may aid practitioners in identifying and overcoming potential barriers to improved mastitis control.


Assuntos
Criação de Animais Domésticos/métodos , Prioridades em Saúde , Mastite Bovina/prevenção & controle , Animais , Bovinos , Feminino , Humanos , Mastite Bovina/epidemiologia , Reino Unido/epidemiologia
14.
J Clin Microbiol ; 54(1): 68-74, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26491180

RESUMO

Multilocus sequence typing was successfully completed on 494 isolates of Streptococcus uberis from clinical mastitis cases in a study of 52 commercial dairy herds over a 12-month period. In total, 195 sequence types (STs) were identified. S. uberis mastitis cases that occurred in different cows within the same herd and were attributed to a common ST were classified as potential transmission events (PTEs). Clinical cases attributed to 35 of the 195 STs identified in this study were classified PTE. PTEs were identified in 63% of the herds. PTE-associated cases, which include the first recorded occurrence of that ST in that herd (index case) and all persistent infections with that PTE ST, represented 40% of all the clinical mastitis cases and occurred in 63% of the herds. PTE-associated cases accounted for >50% of all S. uberis clinical mastitis cases in 33% of the herds. Nine STs (ST-5, -6, -20, -22, -24, -35, -233, -361, and -512), eight of which were grouped within a clonal complex (sharing at least four alleles), were statistically overrepresented (OVR STs). The findings indicate that 38% of all clinical mastitis cases and 63% of the PTEs attributed to S. uberis in dairy herds may be caused by the nine most prevalent strains. The findings suggest that a small subset of STs is disproportionally important in the epidemiology of S. uberis mastitis in the United Kingdom, with cow-to-cow transmission of S. uberis potentially occurring in the majority of herds in the United Kingdom, and may be the most important route of infection in many herds.


Assuntos
Transmissão de Doença Infecciosa , Variação Genética , Mastite Bovina/epidemiologia , Mastite Bovina/transmissão , Infecções Estreptocócicas/veterinária , Streptococcus/classificação , Streptococcus/isolamento & purificação , Animais , Bovinos , Mastite Bovina/microbiologia , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/transmissão , Streptococcus/genética , Reino Unido/epidemiologia
15.
J Dairy Sci ; 98(9): 6029-47, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26117352

RESUMO

The dry period is acknowledged as playing a key role in mastitis epidemiology and yet surprisingly few studies have explored dry period infection dynamics in detail. The aim of this study was to investigate the dynamics of intramammary infection across a cohort of dairy herds in Europe. Five hundred and twenty-two cows were recruited from 12 farms in 6 European countries. All cows received antibiotic dry cow therapy but teat sealants were not used. All quarters of all cows were sampled for bacteriology at drying off and in the week immediately postcalving. Two ipsilateral quarters were also sampled for bacteriology in each cow 2 and 6wk after drying off. Cows were body condition scored and teats assessed for cleanliness at all sampling time points and for the presence of a keratin plug during the dry period. Other cow-level parameters such as historic somatic cell counts and milk yields before drying off were collated from farm records. Univariable and multivariable analyses were undertaken to investigate the etiology, prevalence, and dynamics of infection during the dry period and associated influential factors. In summary, environmental mastitis pathogens predominated. Although gram-positive major pathogens were typically well controlled and did not increase in prevalence across the dry period, gram-negative pathogens generally increased in prevalence. There was an increase in the number of quarters that yielded no growth across the dry period, although this was driven by minor rather than major mastitis pathogen control. Other than the presence of a gram-positive or gram-negative pathogen 6wk after drying off, the measured parameters were not influential when considering their effect on the presence of pathogens postcalving. Analysis also suggested that the early and mid dry period may be more important with respect to the timing of acquisition of infection than previously thought. We observed substantial variation in the etiology and prevalence of different pathogens on different farms with, in all cases, at least one of the 12 herds experiencing the opposite of the others with respect to increases and decreases in pathogen prevalence. Overall, this study confirms the importance of the dry period in mastitis epidemiology but highlights the importance of assessing and understanding infection dynamics on individual units. The lack of influence of the cow and quarter factors measured in this study suggests that herd and management factors may be more influential.


Assuntos
Glândulas Mamárias Animais/microbiologia , Mastite Bovina/epidemiologia , Leite/metabolismo , Criação de Animais Domésticos , Animais , Bovinos , Indústria de Laticínios , Europa (Continente)/epidemiologia , Feminino , Mastite Bovina/microbiologia , Prevalência
16.
Clin Radiol ; 70(8): 822-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25953656

RESUMO

AIMS: To characterise CT findings in renal cell carcinoma (RCC), and establish which features are associated with higher clinical T stage disease, and to evaluate patterns of discrepancy between radiological and pathological staging of RCC. MATERIALS AND METHODS: Preoperative CT studies of 92 patients with 94 pathologically proven RCCs were retrospectively reviewed. CT stage was compared with pathological stage using the American Joint Committee on Cancer (AJCC), 7(th) edition (2010). The presence or absence of tumour necrosis, perinephric fat standing, thickening of Gerota's fascia, collateral vessels were noted, and correlated with pT stage. The sensitivity, specificity, and positive (PPV) and negative predictive values (NPV) for predicting pT stage ≥pT3a were derived separately for different predictors using cross-tabulations. RESULTS: Twenty-four lesions were pathological stage T1a, 21 were T1b, seven were T2a, 25 were T3a, 11 were T3b, four were T3c, and two were T4. There were no stage T2b. Sixty-three (67%) patients had necrosis, 27 (29%) thickening of Gerota's fascia (1 T1a), 25 had collateral vessels (0 T1a), 28 (30%) had fat stranding of <2 mm, 20 (21%) of 2-5mm and one (1%) of >5 mm. For pT stage ≥pT3a, the presence of perinephric fat stranding had a sensitivity, specificity, PPV and NPV of 74%, 65%, 63%, and 76%, respectively. Presence of tumour necrosis had a sensitivity, specificity, PPV, and NPV of 81%, 44%, 54%, and 72%, respectively. Thickening of Gerota's fascia had a sensitivity, specificity, PPV, and NPV of 52%, 90%, 81% and 70%, respectively; and enlarged collateral vessels had a sensitivity, specificity, PPV, and NPV value of 52%, 94%, 88%, and 71% respectively. CONCLUSION: The presence of perinephric stranding and tumour necrosis were not reliable signs for pT stage >T3a. Thickening of Gerota's fascia and the presence of collateral vessels in the peri- or paranephric fat had 90% and 94% specificity, with 82% and 88% PPV, respectively, for the presence of tumour stage for pT stage >T3a. These are considered reliable signs of locally advanced renal cancer.


Assuntos
Carcinoma de Células Renais/diagnóstico por imagem , Neoplasias Renais/diagnóstico por imagem , Carcinoma de Células Renais/patologia , Feminino , Humanos , Neoplasias Renais/patologia , Masculino , Estadiamento de Neoplasias , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos
17.
J Dairy Sci ; 98(3): 1706-20, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25529419

RESUMO

Vaccination can play a useful role in mastitis control programs, although there is a relative dearth of large, well-controlled field efficacy studies. This paper presents the findings on the use of a commercially available vaccine (Startvac, Hipra UK Ltd., Nottingham, UK) on commercial units under UK field conditions. In total, 3,130 cows were recruited from 7 farms and were randomly allocated, within farm, to 1 of 3 groups. The first group received the vaccine following the label regimen, the second group was vaccinated every 90 d following an initial vaccination course, and the third group was left unvaccinated to act as controls. Vaccine efficacy was assessed in the first 120 d of lactation. Data were available for analysis from 1,696 lactations in 1,549 cows. In total, 779 cases of clinical mastitis occurred in the 3 study groups, and we detected no significant difference in the incidence or prevalence of clinical or subclinical mastitis between any of the 3 groups. Mastitis vaccination following the label regimen was associated with a significant reduction in the severity of clinical cases. Cows in this group were at significantly decreased odds of developing clinical mastitis presenting with more than just milk changes [odds ratio: 0.58; 95% confidence interval (CI): 0.35-0.98]. Similarly, each additional vaccination resulted in a cow being at decreased odds of developing clinical mastitis presenting with more than just milk changes (odds ratio: 0.87; 95% CI: 0.77-0.98). Although no cows were culled because of severe mastitis in either of the vaccinated groups, we detected no significant difference in the mastitis-related culling rate between groups. Analysis of milk production data demonstrated that, on average, cows on the label regimen produced a higher volume of milk (231 L; 95% CI: 104.1-357.4) and more milk solids (12.36 kg; 95% CI: 3.12-21.60) than unvaccinated cows in the first 120 d of lactation. Conservative analysis suggested that a return on investment of 2.57:1 could be expected under UK conditions based on increased milk yield alone.


Assuntos
Vacinas Bacterianas/imunologia , Infecções por Escherichia coli/veterinária , Escherichia coli/imunologia , Mastite Bovina/prevenção & controle , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/imunologia , Vacinação/veterinária , Animais , Vacinas Bacterianas/administração & dosagem , Bovinos , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/prevenção & controle , Feminino , Mastite Bovina/microbiologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/prevenção & controle , Fatores de Tempo , Reino Unido , Vacinas de Produtos Inativados/administração & dosagem
18.
Vet J ; 197(3): 682-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23702283

RESUMO

The effectiveness of antibiotic treatment of clinical mastitis (CM) is classically evaluated using bacteriological cure, which provides a concise and objective way of assessing efficacy but does not reflect the situation in the field where persistence or recurrence of clinical signs lead to perceived treatment failure. If clinical signs persist or recur, intramammary (IMM) treatment is often extended or supplemented with parenteral therapy in the expectation of a more efficient elimination of clinical signs or a lower probability of recurrence. The objective of this study was to evaluate the efficacy against clinical persistence or recurrence of three cefquinome treatment regimes, standard 1.5-day intramammary (SIMM), 5-day extended intramammary (EIMM) and combination of EIMM plus 5-day extended parenteral (ECOMBO) treatment. The study was conducted on three dairy farms with a high recurrence rate of environmental mastitis. Efficacy was evaluated using a multi-level model at the quarter and at the cow level, based on the persistence or recurrence of clinical signs at any time during a 105-day period following the end of the initial treatment, independent of pathogen. The most prevalent pathogens were E. coli (16.9%) and S. uberis (11.97%). EIMM and ECOMBO significantly decreased the persistence or recurrence of CM by 8% and 6% at the quarter level and by 9% and 8% at the cow level, respectively. ECOMBO may not reduce the persistence or recurrence of CM beyond EIMM. Whilst extended treatment regimens offered an improved outcome in this study, the producer and practitioner need to carefully consider such regimens from the perspective of prudent antibiotic use.


Assuntos
Antibacterianos/uso terapêutico , Cefalosporinas/uso terapêutico , Mastite Bovina/tratamento farmacológico , Animais , Antibacterianos/administração & dosagem , Bovinos , Cefalosporinas/administração & dosagem , Esquema de Medicação , Feminino , Recidiva
19.
Clin Radiol ; 68(8): e447-52, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22995399

RESUMO

AIM: To assess agreement between uroradiologists and urologists with regards to the timing of non-elective percutaneous nephrostomy (PCN) catheter insertion, and whether any delay produced unacceptable complications. MATERIALS AND METHODS: Standardized data collection forms detailing patient demographics, indications for PCN catheter insertion, blood results, procedural details, and immediate complications were completed by uroradiologists. At the time of referral, patients were stratified by both radiologists and urologists into three groups as follows: group 1 = PCN within 6 h; group 2 = PCN between 6 and 24 h; and group 3 = PCN between 24 and 48 h. RESULTS: One hundred and eighteen non-elective PCN catheter insertions were performed over 2 years. Radiologists stratified 12 patients (10.2%) into group 1, 65 (55.1%) patients into group 2, and 41 (34.7%) patients into group 3. Urologists stratified 14 (11.9%) patients into group 1, 68 (57.6%) patients into group 2, and 36 (30.5%) patients into group 3. There was good agreement between radiologist and urologists (κ = 0.865) on stratification in all but nine (7.6%) cases. Ninety-four point one percent of PCN catheters were inserted within the timeframe stratified by radiologists and urologists, or sooner. Sepsis was associated with a shortened timeframe. Elevated international normalized ratio (INR; >1.5) resulted in an increased timeframe. A major complication rate of 3% is within recommended limits. Fourteen percent of PCN catheter insertions were inserted outside normal working hours. Urgency stratification has decreased the number of cases performed out of hours. CONCLUSION: Radiologists and urologists had good agreement on stratification with an acceptable major complication rate of 3%.


Assuntos
Nefrostomia Percutânea/métodos , Radiografia Intervencionista , Centros de Atenção Terciária/organização & administração , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Biomarcadores/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Prática Médica/estatística & dados numéricos , Análise de Regressão , Estatísticas não Paramétricas , Fatores de Tempo , Resultado do Tratamento
20.
Gen Comp Endocrinol ; 179(2): 265-76, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22974513

RESUMO

Seasonal cycles of reproduction are common in many mammals and these are combined with the necessary energy budgeting for thermoregulatory challenges. Many mammals meet the challenge of changing environmental temperatures in winter by using torpor, a controlled reduction in body temperature and metabolic rate. We aimed to determine the effects of photoperiod and reproductive hormones on the seasonal cycles of reproduction and torpor use in a marsupial that commences reproduction in winter, the stripe-faced dunnart, Sminthopsis macroura. Males and females were placed under LD 14:10 and natural reproductive hormones blocked by either flutamide (males) or mifepristone (females) or tamoxifen (females). Reproductive parameters, metabolic rate and torpor variables were determined. The same animals were then placed under LD 10:14 and given testosterone (males) or progesterone (females) or oestrogen (females). Reproductive parameters, metabolic rate and torpor variables were measured. Body mass and tail widths (fattening indicator) in males were significantly affected by testosterone, and the effects were reversed by hormone blockers. Reproductive parameters were unaffected. Resting metabolic rate and ability to use torpor were not affected by treatment in males, however torpor characteristics, especially torpor bout duration, were affected by presence of testosterone in males. In females, body mass was unaffected by hormone presence, although tail widths were affected. Disruption of reproductive cycles occurred with hormone blockers in females, however, resting metabolic rate was not affected, and only presence of progesterone affected torpor characteristics in females. Our results differ from those found for rodents, where presence of testosterone abolishes the use of torpor in males, and oestrogen inhibits torpor use in females. Our study suggests that, in this mammal, metabolic responses to the presence or absence of reproductive hormones differs between males and females, and there is no absolute endocrinologically-driven reproductive season demarcated from the torpor season.


Assuntos
Adaptação Fisiológica , Metabolismo Basal/efeitos dos fármacos , Regulação da Temperatura Corporal/fisiologia , Estrogênios/fisiologia , Antagonistas de Hormônios/farmacologia , Marsupiais/fisiologia , Progesterona/fisiologia , Reprodução/efeitos dos fármacos , Testosterona/fisiologia , Animais , Temperatura Corporal , Peso Corporal , Ritmo Circadiano , Feminino , Flutamida/farmacologia , Masculino , Mifepristona/farmacologia , Fotoperíodo , Tamoxifeno/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...