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1.
JDS Commun ; 5(1): 38-41, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38223376

RESUMEN

Lameness is an important health and welfare issue that causes considerable economic losses in dairy herds. The objective of this study was to investigate whether the hind feet position score (HFPS) can be used as an auxiliary trait for genetic evaluation of lameness. The HFPS is evaluated by visual scoring of the position of both the hind-digits to the mid-line of the cow's body. The higher the heel height of the lateral claw, the higher is the HFPS, and the higher is the risk for development of lameness. In total, 3,478 records from 1,064 Fleckvieh cows from 35 farms were obtained between September 1, 2021, and March 5, 2022. Data collection was carried out by the regional milk recording organizations. Hind feet position was scored visually by trained personnel during routine milk performance testing in the milking parlor using a 3-class scoring system: score 1 = 0° to <17° indicating a balanced heel height of both the medial and the lateral claw; score 2 = angle of 17° to 24°; score 3 = angle of >24°. After all cows had been milked, locomotion scoring was performed for each animal using a 5-class scoring system with locomotion scores ranging between 1 (normal) and 5 (severely lame). Using HFPS, sensitivity and specificity were 69.5% and 66.8%, respectively, for detecting lameness defined by locomotion score ≥2. For genetic analyses, a bivariate linear animal model was fitted with fixed effects of herd, parity, lactation stage, and classifier, and random effects of animal and permanent environment. Heritabilities for HFPS and locomotion score were 0.07 and 0.10, respectively, and the genetic correlation between the 2 traits studied was 0.80. These results suggest that the HFPS could be used for genetic evaluations to reduce lameness incidence in dairy cattle.

2.
J Dairy Sci ; 107(3): 1669-1684, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37863287

RESUMEN

At the individual cow level, suboptimum fertility, mastitis, negative energy balance, and ketosis are major issues in dairy farming. These problems are widespread on dairy farms and have an important economic impact. The objectives of this study were (1) to assess the potential of milk mid-infrared (MIR) spectra to predict key biomarkers of energy deficit (citrate, isocitrate, glucose-6 phosphate [glucose-6P], free glucose), ketosis (ß-hydroxybutyrate [BHB] and acetone), mastitis (N-acetyl-ß-d-glucosaminidase activity [NAGase] and lactate dehydrogenase), and fertility (progesterone); (2) to test alternative methodologies to partial least squares (PLS) regression to better account for the specific asymmetric distribution of the biomarkers; and (3) to create robust models by merging large datasets from 5 international or national projects. Benefiting from this international collaboration, the dataset comprised a total of 9,143 milk samples from 3,758 cows located in 589 herds across 10 countries and represented 7 breeds. The samples were analyzed by reference chemistry for biomarker contents, whereas the MIR analyses were performed on 30 instruments from different models and brands, with spectra harmonized into a common format. Four quantitative methodologies were evaluated to address the strongly skewed distribution of some biomarkers. Partial least squares regression was used as the reference basis, and compared with a random modification of distribution associated with PLS (random-downsampling-PLS), an optimized modification of distribution associated with PLS (KennardStone-downsampling-PLS), and support vector machine (SVM). When the ability of MIR to predict biomarkers was too low for quantification, different qualitative methodologies were tested to discriminate low versus high values of biomarkers. For each biomarker, 20% of the herds were randomly removed within all countries to be used as the validation dataset. The remaining 80% of herds were used as the calibration dataset. In calibration, the 3 alternative methodologies outperform the PLS performances for the majority of biomarkers. However, in the external herd validation, PLS provided the best results for isocitrate, glucose-6P, free glucose, and lactate dehydrogenase (coefficient of determination in external herd validation [R2v] = 0.48, 0.58, 0.28, and 0.24, respectively). For other molecules, PLS-random-downsampling and PLS-KennardStone-downsampling outperformed PLS in the majority of cases, but the best results were provided by SVM for citrate, BHB, acetone, NAGase, and progesterone (R2v = 0.94, 0.58, 0.76, 0.68, and 0.15, respectively). Hence, PLS and SVM based on the entire dataset provided the best results for normal and skewed distributions, respectively. Complementary to the quantitative methods, the qualitative discriminant models enabled the discrimination of high and low values for BHB, acetone, and NAGase with a global accuracy around 90%, and glucose-6P with an accuracy of 83%. In conclusion, MIR spectra of milk can enable quantitative screening of citrate as a biomarker of energy deficit and discrimination of low and high values of BHB, acetone, and NAGase, as biomarkers of ketosis and mastitis. Finally, progesterone could not be predicted with sufficient accuracy from milk MIR spectra to be further considered. Consequently, MIR spectrometry can bring valuable information regarding the occurrence of energy deficit, ketosis, and mastitis in dairy cows, which in turn have major influences on their fertility and survival.


Asunto(s)
Enfermedades de los Bovinos , Cetosis , Mastitis , Femenino , Bovinos , Animales , Leche , Isocitratos , Acetona , Acetilglucosaminidasa , Progesterona , Citratos , Ácido Cítrico , Ácido 3-Hidroxibutírico , Biomarcadores , Glucosa , Cetosis/diagnóstico , Cetosis/veterinaria , L-Lactato Deshidrogenasa , Mastitis/veterinaria
4.
Eur J Vasc Endovasc Surg ; 39(5): 586-90, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20171910

RESUMEN

OBJECTIVES: The Trans-Atlantic Inter-Society Document on Management of Peripheral Arterial Disease (TASC) gives treatment recommendations depending on the classification of aorto-iliacal or femoro-popliteal vascular pathologies. Therefore, the best treatment could only be offered if the right TASC classification was obtained. The purpose of this study was to assess the interobserver agreement of the evaluation of the TASC II classification for peripheral arterial occlusive disease (PAOD) in magnetic resonance angiography (MRA). PATIENTS AND METHODS: Three hundred arterial segments of 149 patients with a magnetic MRA for PAOD were evaluated according to the TASC II classification. A resident and a consultant for radiology and vascular surgery both performed independent grading. A comparative assessment of the consensus agreement was quantified by the marginal probabilities calculated by generalised estimation equation models, as well as by using the weighted kappa coefficient (kappa), classified according to Altman. RESULTS: In relation to the consensus, the overall agreement was good to excellent for the consultants of radiology and vascular surgery. The consultants obtained a statistically significant higher agreement than did the residents (Odds ratio (OR): 2.86, 95% confidence interval (CI): 2.21-3.69, p<0.001). A significantly higher consensus agreement probability was observed for the surgeons compared with the radiologists (OR: 1.43, 95% CI: 1.11-1.84, p=0.006) and for the femoro-popliteal regions compared with the aorto-iliacal regions (OR: 1.64, 95% CI: 1.12-2.14, p=0.012). CONCLUSION: Although good results can be achieved in the assessment of vascular lesions according to the TASC II document, a simplification of this classification could increase its practicability in a daily clinical routine.


Asunto(s)
Angiografía por Resonancia Magnética , Enfermedades Vasculares Periféricas/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Competencia Clínica , Consultores , Femenino , Humanos , Internado y Residencia , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Oportunidad Relativa , Enfermedades Vasculares Periféricas/clasificación , Enfermedades Vasculares Periféricas/terapia , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad
5.
Clin Radiol ; 65(2): 137-44, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20103436

RESUMEN

AIM: To prospectively assess the value of computer-aided detection (CAD) for the computed tomography (CT) severity assessment of acute pulmonary embolism (PE). MATERIALS AND METHODS: CT angiographic scans of 58 PE-positive patients (34-89 years, mean 66 years) were analysed by four observers for PE severity using the Mastora index, and by CAD. Patients were stratified to three PE risk groups and results compared to an independent reference standard. Interobserver agreement was tested by Bland and Altman and extended kappa (Ke) statistics. Mastora index changes after CAD data review were tested by Wilcoxon signed ranks. RESULTS: CAD detected 343 out of 1118 emboli within given arterial segments and a total of 155 out of 218 polysegmental emboli (segmental vessel-based sensitivity = 30.7%, embolus-based sensitivity = 71.2% false-positive rate = 4.1/scan). Interobserver agreement on PE severity [95% limits of agreement (LOA) = -19.7-7.5% and-5.5-3% for reader pairs 1 versus 2 and 3 versus 4, respectively was enhanced by consensus with CAD data (LOA = -6.5-5.4% and-3.7-2% for reader pairs 1 versus 2 and 3 versus 4, respectively). Simultaneously, the percentual scoring errors (PSE) were significantly decreased (PSE = 35.4+/-31.8% and 5.1+/-8.9% for readers 1/2 and 2/3, respectively, and PSE=27.6 +/- 31% and 3.8 +/- 6.2%, respectively, after CAD consensus; p < or = 0.005). Misclassifications to PE risk groups occurred in 27.6, 24.1, 5.2, and 5.2% of patients for readers 1-4, respectively, (Ke=0.74) and were corrected by CAD consensus in 56.3, 36, 33.3, and 33.3% of misclassified patients, respectively (Ke = 0.83; p < 0.05). CONCLUSION: Radiologists may benefit from consensus with CAD data that improve PE severity scores and stratification to PE risk groups.


Asunto(s)
Embolia Pulmonar/diagnóstico por imagen , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Métodos Epidemiológicos , Femenino , Humanos , Imagenología Tridimensional/métodos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Embolia Pulmonar/patología
7.
Br J Ophthalmol ; 87(5): 615-21, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12714406

RESUMEN

AIM: To evaluate the benefits of macular translocation with 360 degree retinotomy in patients with exudative age related macular degeneration (ARMD). METHODS: A consecutive interventional case series was performed on patients who underwent macular translocation between June 1997 and January 2000 at the department of ophthalmology, University of Aachen, Germany. A retrospective pilot study was set up with a minimum follow up of 12 months in 39 consecutive patients with subfoveal choroidal neovascularisation secondary to ARMD. The surgical technique included pars plana vitrectomy, induction of retinal detachment, 360 degree retinotomy, removal of the choroidal neovascular membranes (CNVM), macular translocation, peripheral laser retinopexy, and silicone oil endotamponade. RESULTS: 18 patients showed predominantly occult CNVM, six patients had predominantly classic CNVM, and 15 showed subretinal haemorrhage. At the 12 month follow up 13 patients (33%) showed an improvement in visual acuity of more than three lines (logMAR scale), 18 patients (46%) retained stable visual acuity with a change of equal or less than three lines (logMAR scale), and eight patients (21%) showed a decrease in visual acuity of more than three lines (logMAR scale). Recurrence of CNVM was observed in three (8%) eyes at 5-11 months postoperatively. Other complications included proliferative vitreoretinopathy with retinal detachment (n=10), peripheral epiretinal membranes (n=9), macular pucker (n=2), corneal decompensation (n=2), and hypotony (n=11). 18 patients (46%) complained about persistent diplopia. CONCLUSION: Macular translocation surgery is able to maintain or improve distant vision in the majority of patients with exudative ARMD. Proliferative vitreoretinopathy and diplopia are the two major complications. A prospective randomised controlled trial comparing macular translocation with observation for patients with the occult form of exudative ARMD may be justified.


Asunto(s)
Mácula Lútea/trasplante , Degeneración Macular/cirugía , Retina/cirugía , Anciano , Anciano de 80 o más Años , Femenino , Angiografía con Fluoresceína/métodos , Fóvea Central/patología , Humanos , Complicaciones Intraoperatorias/etiología , Degeneración Macular/patología , Masculino , Persona de Mediana Edad , Proyectos Piloto , Complicaciones Posoperatorias/etiología , Desprendimiento de Retina/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Agudeza Visual/fisiología
9.
Angew Chem Int Ed Engl ; 38(15): 2154-2174, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10425472

RESUMEN

Combining the advantages of homogeneous and heterogeneous catalysis is still a problem that has not been satisfactorily solved. Chemistry in interphases offers a new approach for overcoming the difficulties, as is described in this article. Owing to the swellable or porous matrix, an interphase represents a state which in the most favorable case is similar to that of a solution. Moreover the proper choice of a mobile hybrid copolymer enables the control of the density and accessibility of the reactive centers, which results in a distinct improvement of the activity of the catalysts (two examples are shown schematically).

10.
BMJ ; 310(6976): 399, 1995 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-7866230
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