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1.
J Dairy Sci ; 106(12): 9164-9173, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37641363

RESUMEN

The objectives of this study were to evaluate different analytical methods to determine colostrum quality in dairy cattle, including one laboratory-based method (ELISA) and 4 on-farm tests. We hypothesized that the colostral IgG concentration using different analytical methods, such as ELISA (mg/mL), digital Brix refractometer (% Brix), colostrometer (specific gravity and mg/mL), an outflow funnel (seconds), and a lateral flow assay (mg/mL), were highly correlated with the reference method, radial immunodiffusion (RID; mg/mL) and would generate comparable results. Colostrum samples were collected from 209 Holstein Friesian cows on 2 commercial dairy farms in Germany. Colostrum weight and colostrum temperature were measured. Test characteristics, such as optimum thresholds, sensitivity, specificity, and area under the curve (AUC) were determined using a receiver operating characteristic curve analyses for each test. Out of 209 colostrum samples assessed by RID, 186 (89%) samples had high quality (≥50 mg IgG/mL), while 23 colostrum samples (11%) showed poor quality with IgG concentrations less than 50 mg/mL. The mean IgG concentration (±SD) was 101.3 ± 45.9 mg/mL and the range was 6.0 to 244.3 mg/mL. The Pearson correlation coefficient (r) between RID and ELISA was r = 0.78. In comparison to RID, Pearson correlation coefficients for the on-farm tests were: r = 0.79 (digital Brix refractometry), r = 0.58 (colostrometer: specific gravity), r = 0.61 (colostrometer: temperature corrected), r = 0.26 (outflow funnel) and r = 0.43 (lateral flow assay), respectively. The optimal threshold to identify high-quality colostrum using ELISA was 50.8 mg/mL with sensitivity 91.3%, specificity 92.3%, and AUC of 0.94. For the on-farm tests sensitivity ranged from 95.7% (Brix refractometry) to 60.9% (lateral flow assay). Specificity ranged from 88.6% (lateral flow assay) to 75.9% (colostrometer: temperature corrected). The AUC ranged from 0.93 (Brix refractometry) to 0.73 (outflow funnel). Based on the AUC, ELISA (0.94) and Brix refractometry (0.93) can be considered highly accurate. In conclusion, the ELISA is accurate to assess colostrum quality. Regarding the on-farm tests only the digital Brix refractometer and the colostrometer were adequate to determine colostrum quality.


Asunto(s)
Líquidos Corporales , Calostro , Embarazo , Femenino , Bovinos , Animales , Calostro/química , Granjas , Inmunoglobulina G/análisis , Líquidos Corporales/química , Curva ROC , Inmunodifusión/veterinaria
2.
J Dairy Sci ; 103(6): 5387-5397, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32278562

RESUMEN

The objective of this study was to evaluate different analytical methods of assessing failure of passive transfer (FPT) in neonatal calves. We hypothesized that 3 different media (i.e., centrifuged serum, centrifuged plasma, filtered plasma) and different analytical methods [i.e., ELISA, capillary electrophoresis (CE), Brix refractometer, and handheld optical refractometer] would be highly correlated with the gold standard radial immunodiffusion (RID) and would generate comparable results. Serum and plasma blood samples were collected from Holstein Friesian calves (n = 216) aged 1 to 7 d, from 2 commercial dairy herds in northeast Germany. The RID analysis showed that 59 of 216 calves (27%) had serum IgG concentrations of <10 mg/mL and 157 calves (73%) had serum concentrations of ≥10 mg/mL. The mean IgG concentration (± standard deviation) was 17.1 ± 9.8 mg/mL, and the range was 0.8 to 47.8 mg/mL. In serum, the correlation between RID and CE was r = 0.97, and between RID and ELISA was r = 0.90; CE and ELISA were also highly correlated (r = 0.89). Both refractometry methods were highly correlated with RID using centrifuged serum, centrifuged plasma, or filtered plasma (Brix refractometer: r = 0.84, 0.80, and 0.78, respectively; handheld optical refractometer: r = 0.83, 0.81, and 0.80, respectively). We determined test characteristics (optimum thresholds, sensitivity, specificity, positive predictive value, negative predictive value, and area under the curve) for CE, ELISA, and the handheld optical and digital refractometers using receiver operating characteristic curve analyses with RID as the reference value. Optimal thresholds for assessing FPT using plasma were higher than for serum, regardless of the method of plasma harvesting. The 4 different devices had comparable areas under the curve, irrespective of the medium used. All analytical methods can be used to assess FPT.


Asunto(s)
Animales Recién Nacidos/inmunología , Bovinos/inmunología , Electroforesis Capilar/veterinaria , Ensayo de Inmunoadsorción Enzimática/veterinaria , Inmunidad Materno-Adquirida , Refractometría/veterinaria , Animales , Calostro , Femenino , Inmunodifusión/veterinaria , Curva ROC , Valores de Referencia , Sensibilidad y Especificidad
3.
J Dairy Sci ; 102(10): 9370-9381, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31378489

RESUMEN

The objective of this study was to evaluate 2 different treatment procedures at the first milking after calving to increase colostrum quantity and to improve colostrum quality in dairy cows. We hypothesized that either exogenous treatment with oxytocin or the presence of the calf at first milking would lead to higher colostrum quantity and higher IgG concentration. The study was conducted from October to December 2017 on a commercial dairy farm in Germany. A total of 567 cows at the time of calving were enrolled, but for the final analyses only 521 animals were considered. The cows were randomly assigned on a daily basis into 1 of 3 groups: (1) control group (n = 177), (2) application of 20 IU of oxytocin i.m. (OXY; n = 163), and (3) presence of the calf (CA; n = 181) before and during milking. Cows in the control and oxytocin group had no contact with their calves after calving and were milked in a separate milking parlor. Cows in the oxytocin group were injected with 20 IU of oxytocin i.m. 3 min before manual stimulation. For cows in the third group, the calf was placed into a calf cart and located in front of the cow 3 min before manipulation of the cow. Colostrum quantity was determined by a digital hanging scale. The colostrum quality was assessed with digital Brix refractometry and ELISA. To evaluate the effect of 2 different treatment procedures, a generalized linear mixed model was constructed using SPSS (SPSS Inc., IBM, Ehningen, Germany). The mean (±SE) colostrum quantity was 4.17 ± 0.30 kg. The treatment procedures and the harvesting time after calving had no effect on colostrum quantity. Parity, calf birth weight, and calving time affected colostrum quantity. Cows in second parity had the lowest quantity of colostrum (3.74 ± 0.37 kg) compared with cows in parity 1 (4.75 ± 0.34 kg) and cows in parity 3 or greater (4.75 ± 0.38 kg). Cows calving during the night (2200 until 0600 h; 4.93 ± 0.37 kg) had the highest quantity of colostrum compared with cows calving in the morning (0600 until 1400 h; 4.17 ± 0.38 kg) or afternoon (1400 until 2200 h; 4.14 ± 0.34 kg). Regarding colostrum quality, 48% of the colostrum samples contained ≥50 mg of IgG/mL. The mean IgG concentration was 54.6 ± 2.80 mg of IgG/mL. Colostrum quality was affected by the treatment procedures, colostrum quantity, parity, calving time, harvesting time after calving, and the calving day during the week. Both treatment procedures (i.e., OXY with mean IgG concentration results of 57.0 mg of IgG/mL and CA with 56.0 mg of IgG/mL) resulted in higher IgG concentrations in colostrum compared with the control group (50.7 mg of IgG/mL). With increasing colostrum quantity, the colostrum quality decreased in primiparous and multiparous cows. A longer time lag between calving and milking negatively affected the colostrum quality. Concentration of IgG was higher for cows in parity 3 or greater (64.6 ± 2.59 mg of IgG/mL) compared with cows in parity 1 (48.5 ± 2.86 mg of IgG/mL) and cows in parity 2 (50.7 ± 2.89 mg of IgG/mL). Cows calving during the night had greater IgG concentrations (60.4 ± 2.92 mg of IgG/mL) compared with cows calving in the morning (51.9 ± 2.98 mg of IgG/mL) or afternoon (51.3 ± 2.71 mg of IgG/mL). Harvesting colostrum on quieter days, such as Sundays, resulted in higher IgG concentrations (61.4 ± 3.70 mg of IgG/mL). The assessment by Brix refractometry resulted in a mean result of 26.0 ± 0.20% Brix. Treatment procedures and the harvesting time after calving had no effect on colostrum quality. A negative association was observed between colostrum quantity and quality in primiparous and multiparous cows determined by Brix refractometry. Brix readings were greater for cows in parity 3 or higher (27.7 ± 0.26% Brix) compared with cows in parity 1 (25.3 ± 0.30% Brix) and cows in parity 2 (25.0 ± 0.32% Brix). In conclusion, the treatment procedure for the first milking is irrelevant to improve the quantity of colostrum. Both treatment procedures, however, increased IgG concentrations as determined by ELISA.


Asunto(s)
Bovinos , Calostro , Industria Lechera/métodos , Leche , Oxitocina/farmacología , Animales , Bovinos/psicología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Alemania , Lactancia/psicología , Modelos Lineales , Madres/psicología , Oxitocina/administración & dosificación , Paridad , Embarazo , Distribución Aleatoria , Refractometría/veterinaria
4.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 75(Pt 4): 505-511, 2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32830708

RESUMEN

The diffraction patterns acquired with transmission electron microscopes gather reflections from all crystallites that overlap in the foil thickness. The superimposition renders automated orientation or phase mapping difficult, in particular when secondary phase particles are embedded in a dominant diffracting matrix. Several numerical approaches specifically developed to overcome this issue for 4D scanning precession electron diffraction data sets are described. They consist either in emphasizing the signature of the particles or in subtracting the matrix information out of the collected set of patterns. The different strategies are applied successively to a steel sample containing precipitates that are in Burgers orientation relationship with the matrix and to an aluminium alloy with randomly oriented Mn-rich particles.

5.
J Dairy Sci ; 102(1): 557-566, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30471908

RESUMEN

The objective of this study was to evaluate a filter system to harvest plasma to assess failure of passive transfer (FPT) in newborn calves. Blood samples (n = 227) for serum and plasma harvesting were collected via jugular vein puncture from Holstein calves aged 1 to 7 d from 4 commercial dairy herds in Northeast Germany. Serum IgG concentrations were determined using a sandwich ELISA. Failure of passive transfer was defined as IgG concentrations <10 mg/mL and used as a gold standard. One handheld optical refractometer (Euromex Holland, Arnhem, the Netherlands) and 2 digital Brix refractometers (device 1: HI 96801 digital refractometer, Hanna Instruments, Woonsocket, RI; device 2: Misco PA201, Misco, Solon, OH) were used to analyze total proteins in serum or plasma. The colostrum uptake of the calf can thus be monitored and calves with FPT can be identified. Serum was obtained through centrifugation. Plasma was obtained through either a filter system or centrifugation. For plasma filtration, approximately 2 mL of lithium heparin blood was injected into the inlet reservoir of a plasma filter (2-Drop-Filter, Pharmadoc, Lübeck, Germany) using a disposable syringe. Receiver operating characteristic curve analyses were used to determine optimum thresholds for each of the 3 devices using different media. Sixty-seven (30%) calves had FPT. For the handheld optical refractometer, the optimum threshold was 5.6 g/dL [sensitivity 70.1%; specificity 80.0%; positive predictive value (PPV) 60.1%; negative predictive value (NPV) 86.2%; area under the curve (AUC) 0.85] using serum. For centrifuged plasma, the optimum threshold was 6.3 g/dL (sensitivity 82.1%; specificity 68.1%; PPV 52.5%; NPV 89.9%; AUC 0.84), and for filtered plasma, the threshold was 6.0 g/dL (sensitivity 56.7%; specificity 90.0%; PPV 70.9%; NPV 82.9%; AUC 0.80). For device 1, the optimum threshold was 8.9% Brix (sensitivity 82.1%; specificity 63.8%; PPV 48.7%; NPV 89.5%; AUC 0.81), 9.4% Brix (sensitivity 76.1%; specificity 73.7%; PPV 55.4%; NPV 87.8%; AUC 0.80), using serum and centrifuged plasma, respectively. For device 2, the optimum threshold was 8.7% Brix (sensitivity 74.6%; specificity 76.2%; PPV 57.4%; NPV 87.5%; AUC 0.83), 9.5% Brix (sensitivity 80.6%; specificity 70.6%; PPV 54.0%; NPV 89.5%; AUC 0.83), and 9.2% Brix (sensitivity 58.2%; specificity 87.5%; PPV 66.6%; NPV 83.0%; AUC 0.80) using serum, centrifuged plasma, and filtered plasma, respectively. Based on the AUC, the 3 devices yielded comparable test characteristics to identify calves with FPT. In conclusion, a filter system can be used to facilitate the evaluation of FPT as a point of care technique in calves without the need for serum centrifugation.


Asunto(s)
Animales Recién Nacidos/inmunología , Bovinos/inmunología , Calostro/inmunología , Filtración/veterinaria , Inmunidad Materno-Adquirida/inmunología , Inmunoglobulina G/sangre , Animales , Proteínas Sanguíneas/análisis , Centrifugación/veterinaria , Femenino , Filtración/métodos , Alemania , Plasmaféresis/veterinaria , Embarazo , Curva ROC , Refractometría/instrumentación , Refractometría/veterinaria , Sensibilidad y Especificidad
6.
Acta Biomater ; 73: 500-508, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29649638

RESUMEN

The nanoscale characteristics of the mineral phase in bone tissue such as nanocrystal size, organization, structure and composition have been identified as potential markers of bone quality. However, such characterization remains challenging since it requires combining structural analysis and imaging modalities with nanoscale precision. In this paper, we report the first application of automated crystal orientation mapping using transmission electron microscopy (ACOM-TEM) to the structural analysis of bone mineral at the individual nanocrystal level. By controlling the nanocrystal growth of a cortical bovine bone model artificially heated up to 1000 °C, we highlight the potential of this technique. We thus show that the combination of sample mapping by scanning and the crystallographic information derived from the collected electron diffraction patterns provides a more rigorous analysis of the mineral nanostructure than standard TEM. In particular, we demonstrate that nanocrystal orientation maps yield valuable information for dimensional analysis. Furthermore, we show that ACOM-TEM has sufficient sensitivity to distinguish between phases with close crystal structures and we address unresolved questions regarding the existence of a hexagonal to monoclinic phase transition induced by heating. This first study therefore opens new perspectives in bone characterization at the nanoscale, a daunting challenge in the biomedical and archaeological fields, which could also prove particularly useful to study the mineral characteristics of tissue grown at the interface with biomaterials implants. STATEMENT OF SIGNIFICANCE: In this paper, we propose a new approach to assess the mineral properties of bone at the individual nanocrystal level, a major challenge for decades. We use a modified Transmission Electron Microscopy acquisition mode to perform an Automated Crystal Orientation Mapping (ACOM-TEM) by analyzing electron diffraction patterns. We tune the mineral nanocrystal size by heating a model bovine bone system and show that this method allows precisely assessing the mineral nanocrystal size, orientation and crystallographic phase. ACOM-TEM therefore has sufficient sensitivity to solve problems that couldn't be answered using X-ray diffraction. We thus revisit the fine mechanisms of bone nanocrystal growth upon heating, a process currently used for bone graft manufacturing, also of practical interest for forensic science and archaeology.


Asunto(s)
Materiales Biocompatibles/química , Huesos/química , Calcificación Fisiológica , Nanopartículas/química , Prótesis e Implantes , Animales , Fenómenos Biomecánicos , Desarrollo Óseo , Huesos/diagnóstico por imagen , Bovinos , Cristalografía por Rayos X , Durapatita , Fémur/química , Fémur/diagnóstico por imagen , Calor , Microscopía Electrónica de Transmisión , Nanocompuestos/química , Polimetil Metacrilato , Temperatura , Ingeniería de Tejidos
7.
J Microsc ; 268(2): 208-218, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28675472

RESUMEN

The diffraction patterns acquired with a transmission electron microscope (TEM) contain Bragg reflections related to all the crystals superimposed in the thin foil and crossed by the electron beam. Regarding TEM-based orientation and phase characterisation techniques, the nondissociation of these signals is usually considered as the main limitation for the indexation of diffraction patterns. A new method to identify the information related to the distinct but overlapped grains is presented. It consists in subtracting the signature of the dominant crystal before reindexing the diffraction pattern. The method is coupled to the template matching algorithm used in a standard automated crystal orientation mapping tool (ACOM-TEM). The capabilities of the approach are illustrated with the characterisation of a NiSi thin film stacked on a monocrystalline Si layer. Then, a subtracting-indexing cycle applied to a 70 nm thick thin foil containing polycrystalline tungsten electrical contacts shows the capability of the technique to recognise small nondominant grains.

8.
Poult Sci ; 96(9): 3199-3213, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28651355

RESUMEN

Health issues like infestation with poultry red mite (Dermanyssus gallinae) and behavioral problems such as feather pecking and cannibalism are reported as current problems on laying hen farms. However, the epidemiological prevalence of these issues in Bavaria, Germany, is not known. The objective of the present survey was to determine the epidemiological prevalence of health and behavioral parameters and the management of hen farms in practice. The survey was sent to all laying hen farmers with more than 1,000 hens in Bavaria, Germany, and contained questions regarding flock management, behavior problems and health issues. The response rate was 40.8% and surveys were answered regarding 293 individual flocks on 147 farms. Three-quarters (77.6%) of the respondents housed their hens under conventional conditions. Farming system had an influence (P ≤ 0.05) on several management measures and the hens' behavior. An infestation of the flocks with poultry red mite was stated in 65.7%, whereby a relationship existed with the farming system (P = 0.001) and the provision of an additional dust bath (P ≤ 0.001). The occurrence of feather pecking (18.5%) was related with the farming system (P = 0.001), the presence of roosters (P = 0.034), the locking of laying hens into the aviary (P = 0.006), not allowing access to the entire litter space after housing (P = 0.044) and nervous (P = 0.002) or chasing behavior (P ≤ 0.001) of laying hens. Similarly, cannibalism (15.0%) was related with locking hens into the aviary system (P ≤ 0.001) and not allowing access to the entire litter space (P = 0.026). According to these results, farmers should avoid locking the hens into the aviary or not allowing access to the entire litter space, because these measures relate to nervous behavior that may result in feather pecking or cannibalism. The provision of an additional dust bath is one of the management measures that can positively influence hens' health and behavior.


Asunto(s)
Agresión , Bienestar del Animal , Canibalismo , Pollos , Infestaciones por Ácaros/veterinaria , Enfermedades de las Aves de Corral/epidemiología , Animales , Pollos/fisiología , Plumas , Femenino , Alemania/epidemiología , Infestaciones por Ácaros/epidemiología , Infestaciones por Ácaros/parasitología , Enfermedades de las Aves de Corral/parasitología , Encuestas y Cuestionarios
9.
Micron ; 92: 43-50, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27866100

RESUMEN

The spatial resolution and the indexing quality obtained with an automated orientation and phase mapping tool are analyzed for different Transmission Electron Microscope (TEM) illumination settings. The electron probe size and convergence angle are studied for two TEM configuration modes referred as microprobe and nanoprobe modes. Using a 10µmC2 aperture in a FEI Tecnai F20 (S)TEM, the nanoprobe mode is used to get a small convergent electron beam while the microprobe mode provides a nearly parallel illumination at the cost of a larger probe size. The nanoprobe configuration enables to increase the spatial resolution (∼1nm vs 3nm) but also affects the fraction of mis-indexed points (15% vs 1%). Indexing errors are attributed to the increase by a factor of three of the convergence angle with respect to the microprobe mode. While intermediate optimum settings may be found and are potentially achievable on electron microscopes providing a 'free lens' control or a larger choice of C2 apertures, it is emphasized that the spatial resolution cannot be considered without reference to the indexing quality and, consequently to the convergence angle.

10.
Poult Sci ; 95(7): 1482-1491, 2016 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-27044875

RESUMEN

The dust-bathing behavior of Lohmann Selected Leghorn hens was compared in 4 enriched colony housing systems and in an aviary system. The enriched colony housing systems differed especially in the alignment and division of the functional areas dust bath, nest, and perches. Forty-eight-hour video recordings were performed at 3 time-points during the laying period, and focal animal sampling and behavior sampling methods were used to analyze the dust-bathing behavior. Focal animal data included the relative fractions of dust-bathing hens overall, of hens bathing in the dust-bath area, and of those bathing on the wire floor throughout the day. Behavior data included the number of dust-bathing bouts within a predefined time range, the duration of 1 bout, the number of and reasons for interruptions, and the number of and reasons for the termination of dust-bathing bouts. Results showed that the average duration of dust bathing varied between the 4 enriched colony housing systems compared with the aviary system. The duration of dust-bathing bouts was shorter than reported under natural conditions. A positive correlation between dust-bathing activity and size of the dust-bath area was observed. Frequently, dust baths were interrupted and terminated by disturbing influences such as pecking by other hens. This was especially observed in the enriched colony housing systems. In none of the observed systems, neither in the enriched colony housing nor in the aviary system, were all of the observed dust baths terminated "normally." Dust bathing behavior on the wire mesh rather than in the provided dust-bath area generally was observed at different frequencies in all enriched colony housing systems during all observation periods, but never in the aviary system. The size and design of the dust-bath area influenced the prevalence of dust-bathing behavior in that small and subdivided dust-bath areas reduced the number of dust-bathing bouts but increased the incidence of sham dust bathing on the wire mesh.


Asunto(s)
Crianza de Animales Domésticos/métodos , Pollos/fisiología , Aseo Animal , Vivienda para Animales , Animales , Polvo , Femenino
12.
Nat Commun ; 5: 5810, 2014 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-25503804

RESUMEN

Optogenetic tools have become indispensable in neuroscience to stimulate or inhibit excitable cells by light. Channelrhodopsin-2 (ChR2) variants have been established by mutating the opsin backbone or by mining related algal genomes. As an alternative strategy, we surveyed synthetic retinal analogues combined with microbial rhodopsins for functional and spectral properties, capitalizing on assays in C. elegans, HEK cells and larval Drosophila. Compared with all-trans retinal (ATR), Dimethylamino-retinal (DMAR) shifts the action spectra maxima of ChR2 variants H134R and H134R/T159C from 480 to 520 nm. Moreover, DMAR decelerates the photocycle of ChR2(H134R) and (H134R/T159C), thereby reducing the light intensity required for persistent channel activation. In hyperpolarizing archaerhodopsin-3 and Mac, naphthyl-retinal and thiophene-retinal support activity alike ATR, yet at altered peak wavelengths. Our experiments enable applications of retinal analogues in colour tuning and altering photocycle characteristics of optogenetic tools, thereby increasing the operational light sensitivity of existing cell lines or transgenic animals.


Asunto(s)
Proteínas de Drosophila/química , Proteínas del Helminto/química , Retinaldehído/química , Rodopsina/química , Rodopsinas Microbianas/química , Potenciales de Acción/fisiología , Animales , Animales Modificados Genéticamente , Conducta Animal , Caenorhabditis elegans/química , Caenorhabditis elegans/efectos de los fármacos , Caenorhabditis elegans/metabolismo , Drosophila melanogaster/química , Drosophila melanogaster/efectos de los fármacos , Drosophila melanogaster/metabolismo , Células HEK293 , Humanos , Larva/química , Larva/efectos de los fármacos , Larva/metabolismo , Luz , Optogenética/instrumentación , Técnicas de Placa-Clamp , Proteínas Recombinantes/química , Retinaldehído/farmacología
13.
Animal ; 8(4): 643-9, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24461060

RESUMEN

In the context of assessing the impact of management and environmental factors on animal health, behaviour or performance it has become increasingly important to conduct (epidemiological) studies in the field. Hence, the number of investigated farms per study is considerably high so that numerous observers are needed for investigation. In order to maintain the quality and validity of study results calibration meetings where observers are trained and the current level of agreement is assessed have to be conducted to minimise the observer effect. When study animals were rated independently by the same observers by a categorical variable the exclusion test can be performed to identify disagreeing observers. This statistical test compares for each variable and each observer the observer-specific agreement with the overall agreement among all observers based on kappa coefficients. It accounts for two major challenges, namely the absence of a gold-standard observer and different data type comprising ordinal, nominal and binary data. The presented methods are applied on a reliability study to assess the agreement among eight observers rating welfare parameters of laying hens. The degree to which the observers agreed depended on the investigated item (global weighted kappa coefficients: 0.37 to 0.94). The proposed method and graphical description served to assess the direction and degree to which an observer deviates from the others. It is suggested to further improve studies with numerous observers by conducting calibration meetings and accounting for observer bias.


Asunto(s)
Crianza de Animales Domésticos/estadística & datos numéricos , Variaciones Dependientes del Observador , Animales , Reproducibilidad de los Resultados
14.
J Anim Physiol Anim Nutr (Berl) ; 98(3): 497-503, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24033508

RESUMEN

The welfare of an animal is ensured if it is able to fully satisfy its essential species-typical needs in all functional aspects of behaviour. In mink, stereotypies and apathy, internal and/or external injuries as well as increased susceptibility to disease have been known to occur as a result of chronic stress. The non-invasive method of analysing faecal cortisol metabolites (FCM) allows conclusions to be drawn about the stress level in the respective housing system. The objective of this study is to find out how the cortisol metabolites content in the faecal changes with increasing age of the mink under semi-natural housing conditions. Thus, 40 American mink (Neovison vison) were housed in two outdoor enclosures imitating natural conditions. Throughout the entire study (13th to 32nd week of life), faecal samples were collected to measure cortisol metabolites. No differences in FCM concentrations between the two outdoor enclosures were found. In the young mink lower, less fluctuating FCM levels were found than in older animals. After the first faecal collection in the 13th/14th week of life, the level of metabolites decreased slightly (p = 0.032; 17th/18th week). From the 22nd/23rd week onwards until the 30th/31st week, shortly before the animals were pelted, continuously increasing concentrations were then measured. Increasing FCM levels with advancing age of the animals are probably attributable to the onset of sexual maturity and/or the respective season. This has to be taken into account in future studies using this method for assessing welfare and when comparing different mink housing systems.


Asunto(s)
Envejecimiento/fisiología , Heces/química , Vivienda para Animales , Hidrocortisona/química , Visón/fisiología , Bienestar del Animal , Animales , Hidrocortisona/fisiología , Estrés Fisiológico
15.
Poult Sci ; 92(5): 1171-6, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23571325

RESUMEN

In the previously performed field study from 2007 to 2009, it became evident that foot pad alterations were already commonly found in turkeys at the age of 6 wk. At this early age, 45% of the clinically examined birds were diagnosed with epithelial necrosis. Therefore, it became important to specifically analyze the situation during the early rearing phase. The present study reflects the prevalence and severity of foot pad alterations of turkey poults up to the age of 35 d (5 wk), starting as early as the age of 3 d. From 24 turkey farms throughout Germany, in general 5,531 turkeys [3,131 male and 2,400 female] of the British United Turkeys 6 strain from 46 flocks, were examined to that effect. Prevalence and severity increased within the duration of stay in the stable, and the prevalence was higher (P < 0.001) during the second visit between d 22 to 35 (factor: 0.94). Therefore, 27.3% (d 3 to 5; male/female: 39.1/25.0%) and 63.3% (d 22 to 35: 61.3/65.7%) of the examined poults had alterations of the foot pads, such as hyperkeratosis (d 3 to 5: 20.4/14.2%; d 22 to 35: 17.6/17.1%), high-grade hyperkeratosis with adhesive dirt (d 3 to 5: 8.7/10.7%; d 22 to 35: 29.2/39.3%), and epithelial necrosis (d 3 to 5: 0.1/0.1%; d 22 to 35: 14.6/9.3%). Female poults showed a higher risk (P < 0.001) of developing food pad alterations (factor: 0.76) than male poults. Male poults developed a higher percentage of epithelial necrosis than hens shortly before relocation. A higher stocking density during the very early rearing phase (d 3 to 5) led to a worse foot pad health status (P < 0.001). Because even mild alterations in the foot pad condition can be indicators for suboptimal design of the rearing environment and are to be seen as a pre-state for severe cases of foot pad dermatitis, it is important to set the main focus on the early rearing phase.


Asunto(s)
Dermatitis/veterinaria , Enfermedades del Pie/veterinaria , Enfermedades de las Aves de Corral/epidemiología , Pavos , Crianza de Animales Domésticos , Animales , Dermatitis/epidemiología , Dermatitis/etiología , Dermatitis/patología , Femenino , Enfermedades del Pie/epidemiología , Enfermedades del Pie/etiología , Enfermedades del Pie/patología , Alemania/epidemiología , Masculino , Enfermedades de las Aves de Corral/etiología , Enfermedades de las Aves de Corral/patología , Prevalencia
16.
Hautarzt ; 58(4): 328-34, 2007 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-17048021

RESUMEN

The frequency of the diagnosis of self-induced injuries is rising, especially in patients with borderline personality disorder. The number of unreported cases is estimated to be high. Self-mutilation typically affects the patient's skin and therefore often presents to dermatologists or general practitioners. Such injuries are often clinically typical; a knowledge of these features is essential for the correct diagnosis and treatment. Multidisciplinary care is essential because of the tendency for overlap with other psychiatric diseases and the risk of suicide. Self-induced injuries are also used to simulate criminal offences and to fraudulently obtain insurance payments. In these cases appropriate diagnosis is important from both a legal and psychiatric point of view. Typical morphological aspects and combination of clinical signs in cases of self-mutilation are presented from forensic point of view to facilitate confirming the diagnosis.


Asunto(s)
Trastorno de Personalidad Limítrofe/prevención & control , Trastorno de Personalidad Limítrofe/psicología , Medicina Legal/métodos , Automutilación/prevención & control , Automutilación/psicología , Piel/lesiones , Trastorno de Personalidad Limítrofe/complicaciones , Alemania , Humanos , Guías de Práctica Clínica como Asunto , Pautas de la Práctica en Medicina , Automutilación/complicaciones
17.
Eur Respir J ; 28(5): 1020-8, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16870662

RESUMEN

Sleepiness is considered to be the major cause of increased traffic accidents in patients with obstructive sleep apnoea syndrome (OSAS). Until now, OSAS patients' driving ability has been assessed using driving simulators, but no assessment in a more natural driving environment has been carried out to date. The aim of the present study was to evaluate driving parameters in OSAS and in controls on a road safety platform, and to compare them with attentional in-laboratory measures before and after continuous positive airway pressure treatment. The parameters measured were: reaction time; distance to stop and number of collisions on the platform; maintenance of wakefulness; and sustained, selective and divided attention in laboratory. Patients exhibited much longer reaction times than controls, leading to a lengthening of the vehicle's stopping distance of 8.8 m at 40 km.h(-1) and to twice the number of collisions. Patients did not demonstrate objective sleepiness or selective and sustained attention deficits. Divided attention deficits were found. However, they did not allow the prediction of real driving impairment. After CPAP treatment, there was no longer any difference between patients and controls regarding driving and attention performances. Driving abilities are significantly impaired in obstructive sleep apnoea syndrome. After continuous positive airway pressure treatment, deficits were normalised. This stresses the importance of evaluating attentional parameters in apnoeic patients and of offering continuous positive airway pressure treatment even to non-sleepy subjects.


Asunto(s)
Conducción de Automóvil , Presión de las Vías Aéreas Positiva Contínua , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/terapia , Atención/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polisomnografía , Tiempo de Reacción/fisiología , Análisis y Desempeño de Tareas , Resultado del Tratamiento
18.
MMW Fortschr Med ; 148(24): 27, 29-32, 2006 Jun 15.
Artículo en Alemán | MEDLINE | ID: mdl-16850804

RESUMEN

Childhood maltreatment manifests in a variety of forms and the underlying causes are manifold. In contrast to other offences involving physical injury, reporting behavior has, statistically speaking, remained unchanged. Patterns of injury must first be established and documented, and this involves a complete examination of the child's body. Depending on the constellation of findings, a radiological diagnosis is usually necessary. When all the findings have been collected, the further steps to be taken--where indicated a report to the police--must be discussed. All the evidence must be recorded, and photos obtained of all externally visible injuries before they fade. It is not the task of the physician to develop criminalistic ambitions, for example, by grilling (a parent) on the cause of the injuries. However, he/she has a duty to do everything necessary to protect the well-being of the child.


Asunto(s)
Maltrato a los Niños/diagnóstico , Notificación Obligatoria , Niño , Maltrato a los Niños/legislación & jurisprudencia , Maltrato a los Niños/terapia , Abuso Sexual Infantil/diagnóstico , Abuso Sexual Infantil/legislación & jurisprudencia , Preescolar , Diagnóstico Diferencial , Femenino , Alemania , Humanos , Lactante , Masculino , Traumatismo Múltiple/diagnóstico , Traumatismo Múltiple/etiología , Radiografía , Síndrome del Bebé Sacudido/diagnóstico , Síndrome del Bebé Sacudido/diagnóstico por imagen , Heridas y Lesiones/diagnóstico , Heridas y Lesiones/etiología
20.
Int J Legal Med ; 119(4): 213-6, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15830244

RESUMEN

The aim of this clinicopathological study was to determine the frequency of infant deaths due to unnatural causes among cases of sudden and unexpected infant death. Nine institutes of legal medicine in Germany that took part in the German study on Sudden Infant Death Syndrome (GeSID), representing 35% of the German territory, investigated in a 3-year period (from 1998 to 2001) 339 cases of infant death that were not expected to be due to unnatural causes from the first external examination. All cases were investigated by complete, standardised, post-mortem examination including death scene investigation, autopsy, histology, toxicology and neuropathology. The frequency of unnatural deaths was 5.0% (n=17). The causes of death were head injury (n=7), suffocation (n=5), poisoning (n=2), neglect (n=2) and septicaemia due to aspiration of a foreign body (n=1). Two deaths were unsuspected accidents and 12 were due to infanticide. In 3 cases, it was not possible to differentiate between accidental death and infanticide. A complete postmortem examination including an analysis of the clinical history, death scene investigation, autopsy, histology, toxicology, and neuropathology is mandatory to differentiate sudden and unexpected deaths due to natural causes (e.g. SIDS) and cases of unnatural death.


Asunto(s)
Causas de Muerte , Infanticidio , Muerte Súbita del Lactante/patología , Heridas y Lesiones/patología , Autopsia/métodos , Estudios de Casos y Controles , Alemania/epidemiología , Humanos , Lactante , Recién Nacido , Infanticidio/estadística & datos numéricos , Heridas y Lesiones/mortalidad
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