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OBJECTIVE: To determine the accuracy of asymmetry indices of ground reaction forces (GRF) for diagnosis of hind limb lameness in dogs. ANIMALS: 36 healthy dogs and 13 dogs with naturally acquired cranial cruciate ligament rupture or hip dysplasia. PROCEDURES: Lameness for affected dogs ranged from not detectable to minor and constant. While dogs trotted on an instrumented treadmill, GRF variables were recorded and analyzed with asymmetry indices. Each index was tested for its ability to discriminate between healthy and affected dogs. Combinations of several indices were also assessed. RESULTS: Vertical force variables had better accuracy than craniocaudal force variables. Peak vertical force was the most accurate variable. Partial asymmetry during trotting was detected in healthy dogs. A multivariate approach that used peak vertical force and maximal rising slope yielded the optimum combination to distinguish between healthy and affected dogs. In addition, sensitivity of 92% or specificity of 95% may be achieved with 2 cutoff values while simultaneously maintaining specificity or sensitivity, respectively, at > 85%. CONCLUSIONS AND CLINICAL RELEVANCE: Asymmetry indices of GRFs were accurate for detection of hind limb lameness in dogs. This is particularly relevant for study designs in which only a single gait evaluation is possible.  相似文献   
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The Asian spotted wing drosophila, Drosophila suzukii, has recently become a serious pest of soft fruits in Europe. Classical biological control through the introduction of larval parasitoids from its native range in Asia is presently being considered. However, host specificity of potential biological control agents has to be determined to avoid releasing species that may have unintended non-target impacts. Larvae of six different European non-target fly species and the target D. suzukii were exposed either on diet or blueberries to three Asian larval parasitoids, Asobara japonica, Leptopilina japonica, and Ganaspis cf. brasiliensis, and one European species, Leptopilina heterotoma. Asobara japonica showed the lowest specificity, attacking and developing in all Drosophilidae. Leptopilina japonica successfully parasitized two non-target Drosophilidae, D. melanogaster and D. subobscura, with one singly progeny emerging from D. immigrans. Ganaspis cf. brasiliensis had the highest level of specificity but variations occurred between two geographical populations tested. A Japanese population was strictly specific to D. suzukii, whereas another population from China parasitized D. suzukii, D. melanogaster and sporadically D. subobscura. The European L. heterotoma successfully developed in D. melanogaster, D. subobscura and occasionally in D. immigrans, but nearly all eggs and larvae in D. suzukii were encapsulated. These results show that Ganaspis cf. brasiliensis is the species with the highest potential for biological control, but more studies are needed on its taxonomic status and the existence of biotypes or cryptic species varying in their specificity before field releases can be conducted in Europe.  相似文献   
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To assess the repeatability of kinetic gait analysis with a treadmill, 28 sound adult dogs were made to trot on an instrumented system. Vertical ground reaction force variables (Peak PFz and Impulse IFz) were collected by 10-s recordings, once a week, 4 weeks in succession. Data were analysed using a repeated-measures two-way ANOVA to investigate habituation to treadmill locomotion. Recorded data were stabilized from the end of the first and second sessions for IFz and PFz, respectively. The percentages of variance attributable to dogs, weeks, minutes and repetitions were, respectively, 72%, 10%, 7%, and 11% for PFz and 84%, 7%, 3%, and 6% for IFz. Habituation occurred after a single training session. Good repeatability was determined by a low coefficient of variation (3.4-4.7%). Adding a treadmill to kinetic gait analysis deserves consideration: reliable data are easily recorded using appropriate habituation and statistical model.  相似文献   
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  • 1. A study on the genetic variability of the white‐clawed crayfish was carried out based on mitochondrial cytochrome oxidase subunit I gene sequences. The sequences applied were more informative regarding white‐clawed crayfish genetic variability than others previously used.
  • 2. Two haplotypes were found to exist in the Iberian Peninsula. The haplotypes exhibit a strong geographic subdivision (ΦST=0.83). One of the Iberian haplotype s was similar to north Italian haplotypes and the second differed in only one mutation. This pattern of genetic variability contrasts with those found in glacial refugial areas of France, Italy and the Balkan Peninsula.
  • 3. Two hypotheses on the origin of the white‐clawed crayfish in the Iberian Peninsula are discussed: (i) one based on an anthropogenic origin, and (ii) a second based on a successive number of postglacial ancient and recent bottlenecks, i.e. the disjunction between Iberian and Italian populations of white‐clawed crayfish species is due to competition between A. italicus and A. pallipes, in addition to the impact of crayfish plague and human translocations.
  • 4. New references for the white‐clawed crayfish in the Iberian Peninsula were found in medieval and Arabic texts. The results show that this species has been thriving in this peninsula since ancient periods and that its indigenous status should not be questioned.
  • 5. Conservation action and plans should consider the low genetic diversity as a limitation for farm‐raising specimens more adapted and resistant to changing environments and diseases.
Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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The murine norovirus (MNV) is a recently discovered mouse pathogen, representing the most common contaminant in laboratory mouse colonies. Nevertheless, the effects of MNV infection on biomedical research are still unclear. We tested the hypothesis that MNV infection could alter immune response in mice with acute lung infection. Here we report that co-infection with MNV increases survival of mice with Pseudomonas aeruginosa acute lung injury and decreases in vivo production of pro-inflammatory cytokines. Our results suggest that MNV infection can deeply modify the parameters studied in conventional models of infection and lead to false conclusions in experimental models.  相似文献   
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Bedrock depth provides important information for many environmental and agricultural applications, such as shallow groundwater monitoring, the determination of soil water availability, and the estimation of crop production potential. Direct estimates of bedrock depth from destructive soil observations are discontinuous and too expensive to be used in large areas. Geophysical methods are often cited as possible alternatives. However, their ability to provide reliable estimations of bedrock depth is known to depend greatly on local site characteristics. Therefore, combining geophysical methods based on different physical parameters may help to provide better predictions. This study examines the ability of the Spectral Analysis of Surface Waves (SASW) method combined with the classical high resolution Electrical Resistivity Tomography (ERT) method to predict soil depths in a 500 m ranged Mediterranean hillslope (Southern France) with increasing soil depths along the slope. SASW was performed using the data measured in the field with classical seismic equipment (impulse source and geophones distributed along a line). In the same place, eight transects of ERT (Wenner–Schlumberger array, 1 m electrode spaced) were measured under wet and dry conditions. To calibrate the geophysical measurements, 81 boreholes (from two to 5 m deep) were interpreted to determine the bedrock depth, which was defined as the occurrence in the depth of heterogeneous marine Miocene loose sandstone with centimetric laminations. ERT and SASW were found to have highly variable performances for predicting separately the bedrock depth along the hillslope. SASW correctly predicted the bedrock depth in the lower part of the hillslope, whereas the data from ERT were disrupted by shallow permanent groundwater. Conversely, ERT correctly predicted bedrock depth within the upper part of the hillslope, whereas a high variability of SASW data near the topsoil caused difficulties for bedrock depth prediction. From these results, it was possible to define an estimator of bedrock depth according to the presence of shallow groundwater, which varies along the slope, such that more importance is given to ERT estimates in the upper part of the hillslope and more importance is given to SASW in the lower part. This study shows the usefulness of such a sensor combination to estimate soil properties when the uncertainties of making predictions vary according to the geophysical methods.  相似文献   
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Diarrhea represents one of the most frequent disorders in dogs. In puppies, degradation of feces quality is associated with a reduced daily weight gain and an increased risk of death. Prevention of diarrhea in puppies requires a global approach encompassing enteropathogens, environment and management practices especially when housed in groups. The purpose of this study was to determine prevalence of enteropathogens in puppies in breeding kennels and to identify risk factors of diarrhea. Two hundred and sixty six puppies (between 5 and 14 weeks of age) from 29 French breeding kennels were included. For each kennel, data about environment, management of the kennel and puppies’ characteristics (age, sex and breed) were collected. For each puppy, fecal consistency and fecal excretion of enteropathogens (viruses and parasites) was evaluated. At least one enteropathogen was identified in 77.1% of puppies and 24.8% of puppies presented abnormal feces. The main risk factor of weaning diarrhea was fecal excretion of canine parvovirus type 2 (odds ratio = 5; confidence interval 95%: 1.7–14.7). A targeted sanitary and medical prophylaxis against canine parvovirus type 2 should be implemented to decrease risk of weaning diarrhea.  相似文献   
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