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51.
Using mortality data for early detection of Classical Swine Fever in The Netherlands 总被引:1,自引:0,他引:1
Early detection of the introduction of an infectious livestock disease is of great importance to limit the potential extent of an outbreak. Classical Swine Fever (CSF) often causes non-specific clinical signs, which can take considerable time to be detected. Currently, the disease can be detected by three main routes, that are all triggered by clinical signs. To improve the early detection of CSF an additional program, based on mortality data, aims to routinely perform PCR tests on ear notch samples from herds with a high(er) mortality. To assess the effectiveness of this new early detection system, we have developed a stochastic model that describes the virus transmission within a pig herd, the development of disease in infected animals and the different early detection programs. As virus transmission and mortality (by CSF and by other causes) are different for finishing pigs, piglets and sows, a distinction is made between these pig categories. The model is applied to an extensive database that contains all unique pig herds in The Netherlands, their herd sizes and their mortality reports over the CSF-free period 2001-2005. Results from the simulations suggest that the new early detection system is not effective in piglet sections, due to the high mortality from non-CSF causes, nor in sow sections, due to the low CSF-mortality. In finishing herds, the model predicts that the new early detection system can improve the detection time by two days, from 38 (27-53) days to 36 (24-51) days after virus introduction, when assuming a moderately virulent virus strain causing a 50% CSF mortality. For this result up to 5 ear notch samples per herd from 8 (0-13) finishing herds must be tested every workday. Detecting a source herd two days earlier could considerably reduce the number of initially infected herds. However, considering the variation in outcome and the uncertainty in some model assumptions, this two-day gain in detection time is too small to demonstrate a substantial effect of the new early detection system based on mortality data. But when the alertness of herd-owners and veterinarians diminishes during long CSF-free periods, the new early detection system might gain in effectiveness. 相似文献
52.
Neirinckx E Croubels S De Boever S Remon JP Bosmans T Daminet S De Backer P Vervaet C 《Research in veterinary science》2011,91(3):415-421
As a part of ongoing research to further elucidate frequent and species-specific causes of differences in oral bioavailability, a 3 mg/kg dose of racemic ketoprofen, a high permeability/low solubility compound in the human biopharmaceutics classification system, was administered intravenously and orally to different species. Due to possible enantioselective disposition kinetics and inversion, enantiomers were quantitated separately using a stereospecific HPLC assay. The absolute bioavailability of R(−) and S(+) ketoprofen in chickens, turkeys, dogs and pigs was 31.5% and 52.6%, 42.6% and 32.5%, 33.6% and 89.1%, and 85.9% and 83.5% respectively. Incomplete bioavailability in poultry is probably due to incomplete absorption in addition to first-pass elimination. Low bioavailability of R(−) ketoprofen in dogs, strongly indicates first-pass metabolism. High bioavailability of S(+) ketoprofen in dogs and both enantiomers in pigs confirms that absorption of these substances is complete and controlled by gastric emptying rather than dissolution. 相似文献
53.
A field study was conducted to evaluate three real-time weighing systems to measure sugarbeet yield. Two systems permit use of the storage hopper onboard the harvester. The effects of tare on yield measurement were investigated. Parallel yield data from the three systems were compared. There was a strong relationship between systems as sugarbeet flow rates changed. High standard deviations were found for all product flow sensors. There was no statistical difference between two of the sensors, but there was for the other. One system provided unacceptable results. One of the systems provided reasonable accuracy and permitted use of the onboard storage hopper. 相似文献
54.
Mathias De Backer Hossein Alaei Erik Van Bockstaele Isabel Roldan-Ruiz Theo van der Lee Martine Maes Kurt Heungens 《European journal of plant pathology / European Foundation for Plant Pathology》2011,130(3):325-338
Puccinia horiana is the causal agent of chrysanthemum white rust or Japanese rust. This microcyclic autoecious rust has a quarantine status
and can cause major damage in the commercial production of Chrysanthemum x morifolium. Given the international and often trans-continental production of planting material and cut flowers of chrysanthemum and
the decreasing availability of registered fungicides in specific regions, breeding for resistance against P. horiana will gain importance and will need to involve the appropriate resistance genes for the pathotypes that may be present. As
pathotypes have not been well characterized in this system, the main objective was to build an international collection of
isolates and screen these on a large collection of cultivars to identify different pathotypes. Using a robust and high throughput
bioassay, we tested 36 selected cultivars with 22 individual single-pustule isolates of P. horiana. The isolates originated from three different continents over 4 different collection years and included some isolates from
cultivars previously reported as resistant. In most cases the bioassays resulted in a clear scoring of interaction phenotypes
as susceptible or resistant, while in several cases consistent intermediate phenotypes were found, often on specific cultivars.
Twenty-four of the cultivars gave a differential interaction phenotype profile. All isolates produced a unique profile, infecting
a minimum of 4 and a maximum of 19 differential cultivars. Based on the Person analysis of these profiles, this pathosystem
contains at least seven resistance genes (and seven avirulence genes), demonstrating the highly complex race structure in
this pathosystem. 相似文献
55.
Pharmacokinetics of a lidocaine patch 5% in dogs 总被引:2,自引:0,他引:2
Weiland L Croubels S Baert K Polis I De Backer P Gasthuys F 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2006,53(1):34-39
Lidocaine is increasingly used in transdermal drug delivery systems for different pain conditions in human medicine whereby several pharmacokinetic studies have demonstrated minimal systemic absorption in men. In the present study, the pharmacokinetics of a lidocaine patch 5% was studied in six dogs. In the first experiment, one single lidocaine patch was applied for 12 h to the lateral side of the thorax after removing the hair either by clipping or by the application of a depilatory agent, according to a two-way crossover design. No potential adverse effects induced by the patches were observed in either group. In dogs with clipped hair, a mean peak plasma lidocaine concentration of 62.94 ng/ml was obtained after 10.67 h. In the depilatory group, a mean peak plasma concentration of 103.55 ng/ml was reached after 9.27 h. Significant differences in the AUC(0 --> infinity), C(max), k(a) and T(1/2a) were noticed between the two groups. No significant differences were found for the elimination parameters and for T(max). In the second experiment, the patches were applied for 60 h to the clipped skin in order to study the absorption kinetics after a prolonged application period. There, the mean peak lidocaine plasma concentration was 45.18 ng/ml achieved after 24 h and a final concentration of 29.37 ng/ml was obtained at 60 h. In conclusion, all dogs tolerated the transdermal lidocaine patch well. The results of this study suggest that there is an overall minimal absorption from the lidocaine patch. However, the application of a depilatory agent leads to a more rapid and increased absorption of lidocaine. 相似文献
56.
De Clercq D van Loon G Baert K Tavernier R Croubels S De Backer P Deprez P 《Veterinary journal (London, England : 1997)》2006,172(1):129-134
Six horses without underlying cardiac disease were presented because of atrial fibrillation of between 5 and 12 months duration. These horses received an intravenous amiodarone treatment of 5mg/kg/h for 1 h followed by 0.83mg/kg/h for 23h and subsequently 1.9mg/kg/h for 30h. During treatment, clinical signs were monitored and a surface ECG and an intra-atrial electrogram were recorded. Infusion was discontinued when sinus rhythm or side effects occurred. Four horses successfully cardioverted, of which one showed symptoms of hind limb weakness and weight shifting. Two horses did not cardiovert and showed similar side effects. In all horses, side effects disappeared within 6h after termination of treatment. Cardiac side effects, such as pro-arrhythmia, were not seen in any of the horses. Total bilirubin slightly increased in three horses and normalised within four days. It was concluded that amiodarone has the potential to treat naturally occurring chronic atrial fibrillation in horses, although further research is needed to refine the infusion protocol. 相似文献
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Sulfonamides and trimethoprim are chemotherapeutics that are extensively used in various animal species. Little information about the pharmacokinetics of these compounds in chickens exists in the literature. In this study, a new commercial formulation of sulfadiazine in combination with trimethoprim was administered both intravenously and orally, according to a crossover design, to healthy, 7-week-old broilers. The plasma concentrations of the drugs were determined by validated high-performance liquid chromatographic methods, and pharmacokinetic parameters were calculated. After intravenous or oral administration of trimethoprim (6.67 mg/kg body weight) and sulfadiazine (33.34 mg/kg body weight), both active substances were rapidly eliminated from the plasma. There was a mean half-life of 1.61 h for trimethoprim and 3.2 h for sulfadiazine. The apparent volumes of distribution (2.2 and 0.43 L/kg, respectively, indicated that the tissue distribution of trimethoprim was more extensive than that of sulfadiazine. The oral bioavailability was approximately 80% for both components. 相似文献
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