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21.
Use of a national identification database to determine the lifetime prognosis in cattle with necrotic laryngitis and the predictive value of venous pCO2 
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Fouad Mokrini Lieven Waeyenberge Nicole Viaene Fouad Abbad Andaloussi Maurice Moens 《European journal of plant pathology / European Foundation for Plant Pathology》2013,137(2):403-413
Pratylenchus penetrans is one of the most economically damaging plant-parasitic nematodes and is found on a wide variety of crops. Correct identification and quantification of this nematode are necessary for providing advice to farmers, but are not easily obtained with the traditional way of microscopic observation. We developed a qPCR assay to detect and quantify P. penetrans in a short but accurate manner. A qPCR primer set, including two primers and a TaqMan probe, was designed based on the sequence of the β-1,4-endoglucanase gene. The assay was optimized by using the primers in a qPCR assay with SYBR green I dye and setting the qPCR program to different annealing temperatures ranging from 60 °C to 64 °C. Based on the Ct-values, we retained the program with an annealing temperature of 63 °C. The assay with the probe was very sensitive as it was able to detect a single individual of P. penetrans, even when mixed with up to 80 individuals of P. thornei. The specificity of the reaction was confirmed by the lack of amplification of DNA from 28 populations of 18 other Pratylenchus species and from plant-parasitic nematodes from nine other genera. DNA from 21 different isolates from P. penetrans was amplified. DNA extraction from 80 individuals and quantification by qPCR was repeated four times; Ct-values showed consistent results (Ct?=?24.4?±?0.4). A dilution series from DNA of P. penetrans resulted in a standard curve showing a highly significant linearity between the Ct-values and the dilution rates (R2?=?0.99; slope?=??3.23; E?=?104 %). The tests showed a high correlation between the real numbers of nematodes and the numbers detected by the qPCR. The developed qPCR assay provides a sensitive means for the rapid detection and reliable quantification of individuals of this pest. This method does not require expertise in nematode taxonomy and morphology, and can be used as a rapid diagnostic tool in research, as well as in diagnostic labs and extension services advising farmers for pest management. 相似文献
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Benny De Cauwer Nina Biesemans Sander De Ryck Lieven Delanote Karel Dewaele Koen Willekens Thijs Vanden Nest Dirk Reheul 《Weed Research》2021,61(1):55-67
Galinsoga quadriradiata and Galinsoga parviflora are very troublesome weeds in many organic vegetable crops in Europe. A very straightforward method to keep Galinsoga infestations under control is by targeting the Galinsoga seedbank. To identify cropping systems able to reduce the seedbank size in vegetable‐based cropping systems, the relationships between the seedbank size of Galinsoga species and prevailing soil/crop management practices and pedo‐hydrological conditions were investigated. Hereto, the seedbank of the 0–20 cm topsoil layer was sampled in 50 organic vegetable fields and analysed according to the seedling emergence method. Field history data were collected for the past 5 years, and physical, chemical and microbial soil quality was determined. Galinsoga quadriradiata was the most frequent and abundant Galinsoga species in the weed seedbank. The genus Galinsoga was present in 90% of the soil weed seedbanks of organic vegetable fields but displayed wide variation in abundance. Smallest Galinsoga seedbanks were found in fields that were predominantly tilled with non‐inversion implements or rotationally ploughed, and continuously cropped with competitive crops during the entire growing season (April 15‐November 15). Contrary to G. quadriradiata, seedbank size of G. parviflora was closely related to soil organic carbon content and sand fraction. Remarkably, soils with a low level of easily plant‐available phosphorus and concomitant high activity of arbuscular mycorrhizae had smaller G. quadriradiata seedbanks. To reduce Galinsoga infestations, fields should preferably be tilled without soil inversion, fertilised with organic amendments with low content of readily plant‐available phosphorus and cropped with competitive crops all season long. 相似文献
24.
Winy Messens Lieve Herman Lieven De Zutter Marc Heyndrickx 《Veterinary microbiology》2009,138(1-2):120-131
This study aims to investigate the genetic diversity of thermotolerant Campylobacter in commercial broiler flocks and in the environment of broiler farms in Belgium. Seven out of 18 investigated flocks became colonized during rearing. Fluorescent amplified fragment length polymorphism (FAFLP), pulsed field gel electrophoresis (PFGE), restriction fragment length polymorphism of the flagellin A gene (flaA-RFLP) and antimicrobial resistance profile (ARP) were used for typing of the isolates. By the combination of FAFLP and PFGE, 22 Campylobacter genotypes could be distinguished. Colonization was almost exclusively with Campylobacter jejuni and unique genotypes were found in each flock. Multiple genotypes were detected in the broilers of 3 flocks, either simultaneously or successively. In 5 flocks, strains that were resistant to at least one antibiotic (mostly tetracycline) were found. The presence of other broiler houses on the farm did not result in a higher probability of colonization. The nipple water was contaminated with the same genotype as the broilers, illustrating its importance for transmission of Campylobacter. The same genotype was detected in a water puddle and in the broiler flock during rearing in 3 flocks. Once, the same genotype was isolated from the ditch water shortly before it was detected in the broilers. 相似文献
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Stijn Schauvliege DVM Annelies Van den Eede DVM Luc Duchateau PhD Frederik Pille DVM PhD Diplomate ECVS Lieven Vlaminck DVM PhD Diplomate ECVS Frank Gasthuys DVM PhD Diplomatic ECVAA 《Veterinary anaesthesia and analgesia》2009,36(2):101-109
ObejctiveTo investigate the influence of calcium chloride (CaCl2) on the cardio–respiratory effects of enoximone in isoflurane anaesthetized ponies.Study designProspective consecutive experimental trial.AnimalsSix healthy ponies, weighing 287 ± 55 kg were included in this study.MethodsAfter sedation (romifidine, 80 μg kg?1), anaesthesia was induced with midazolam (0.06 mg kg?1) and ketamine (2.2 mg kg?1) and maintained with isoflurane in oxygen. The ponies’ lungs were ventilated to maintain normocapnia. After 90 minutes, a bolus of enoximone (0.5 mg kg?1) was administered, followed by a CaCl2 infusion (0.5 mg kg?1 minute?1 over 10 minutes) (treatment EC). Sodium, potassium, ionized and total calcium concentrations, cardiovascular variables and blood–gases were measured in the 120 minutes after treatment. Using a mixed model anova, the results were compared to those of a previous report [Vet Anaesth Analg, 34 (2007) 416], evaluating the effects of 0.5 mg kg?1 enoximone in the same ponies and under identical circumstances (treatment E). Both an overall comparison and comparisons at specific time points after treatment were performed (α = 0.05).ResultsAlthough ionized and total calcium concentrations were higher during treatment EC, the cardio–respiratory effects of enoximone were comparable for both treatments. A small but significant difference in packed cell volume was detected.Conclusions and clinical relevanceCalcium chloride did not enhance the effects of enoximone in normocalcaemic anaesthetized ponies. 相似文献
26.
Nele Defoirdt Inge Wuijtens Lieven De Boever Hugo Coppens Jan Van den Bulcke Joris Van Acker 《Annals of Forest Science》2012,69(8):939-946
Context
Customers have limited tolerances for colour differences between oak wood elements in parquetry or furniture, whereas manufacturers are in need of an objective method to communicate possible differences in their products.Aims
This study is aimed at grading oak wood boards in objectively defined colour classes in correspondence with the visual assessment by an expert panel.Methods
First, the most suitable spectrophotometer for measurements approximating the perception of the human eye was selected. Then, three colour grading algorithms were evaluated: one based on the smallest distance towards the centre of the colour subspaces, the second using a classification tree and the last implementing the CIEDE2000 colour difference formula to determine tolerance ellipsoids.Results
Statistical analysis using a classification tree and CIEDE2000 tolerance ellipsoids classified the specimens in good accordance with visual assessment, with a 6 and 5?% misclassification, respectively.Conclusions
The colour grading methodology can be adapted to particular grading purposes and is proposed as a basis for development of an inline colour grading system to be added to commonly used defect detection scanners. 相似文献27.
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Jeroen Staelens Lieven Nachtergale An De Schrijver Margot Vanhellemont Karen Wuyts Kris Verheyen 《Annals of Forest Science》2011,68(1):89-98