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11.
Inclusion bodies, indistinguishable from rabies inclusion bodies (Negri bodies), were found in the brains of 8 nonrabid dogs. The inclusions were compared to Negri bodies present in neurons of rabies-positive animals and examined for the presence of rabies virus by a combination of immunoperoxidase staining (7 cases), fluorescent antibody (FA) staining (1 case), and transmission electron microscopy (4 cases). Positive immunoperoxidase staining for rabies was obtained in brain tissues from FA rabies-positive animals. All brain tissues from the 7 dogs stained by the immunoperoxidase method and the brain from the 1 dog stained by the FA method were negative for rabies. Rabies virus was not found in inclusion-containing neurons in the cases examined by transmission electron microscopy. These results emphasize the importance of FA testing and mouse inoculation for the diagnosis of rabies.  相似文献   
12.
Students in veterinary schools can experience stress in balancing the different demands on them-academic, interpersonal, intrapersonal, and professional or work related-as well as managing potential conflict between animal and human interests. Practicing veterinarians report many similar stressors and reactions. Stressful stimuli produce stress reactions that can be inimical to physical and psychological well-being, and students' performance in veterinary programs can be adversely affected if they do not have coping resources. While there has been some research into stress among university students in general, and among medical students in particular, there is little on the experience of veterinary students. This article describes a study by the School of Psychology, commissioned by the Department of Veterinary Clinical Sciences, at Murdoch University in Western Australia. It was designed to investigate the levels and causes of stress among, and the frequency and type of coping strategies used by, fourth- and fifth-year students. Results indicate that the students in this cohort faced frequent stressors and felt at least moderately stressed but did not routinely and systematically use a range of coping strategies. Academic stressors and perceived responsibilities attached to moving into practical or professional areas figured strongly and were associated with higher levels of stress in the students, in particular physical sequelae. Though the numbers were small, it is of concern that some students were using measures that were potentially harmful. Some recommendations are made here about measures that veterinary programs may be able to incorporate to address stress in their students. Information is included on current strategies within the curriculum to manage potential stressful situations as part of students' professional development.  相似文献   
13.
It is difficult to predict the size of pituitary corticotroph tumors in dogs with Cushing's disease (pituitary-dependent hyperadrenocorticism [PDH]) without pituitary imaging techniques. The purpose of this study was to examine the relationship between plasma adrenocorticotropin hormone (ACTH) precursor concentration and pituitary size in dogs with Cushing's disease. Plasma concentrations of ACTH precursors (pro-opiomelanocortin [POMC]/pro-ACTH) and pituitary tumor height/brain area were measured in 36 dogs with pituitary corticotroph adenomas of various sizes. There was a correlation between tumor size (measured as the pituitary tumor height/brain area ratio [P/B]) and POMC/pro-ACTH concentration (r = .70; P < .0001). Dogs with P/B > or = 0.40 x 10(-2) mm(-1) had higher concentrations of ACTH precursors than dogs with P/B < 0.40 x 10(-2) mm(-1) (median concentration 85 pmol/L, range 15-1,350 pmol/L, n = 14 versus 15 pmol/L, range 15-108 pmol/L, n = 22; P < .0001). With a threshold of 35 pmol/L of POMC/pro-ACTH concentration, the estimated sensitivity and specificity of the kit were 93% (95% confidence interval [CI], 79-100%) and 86% (95% CI, 73-100%), respectively. We interpret these data as indicating that measurement of POMC and pro-ACTH might be of value in the characterization of tumor size in dogs with Cushing's disease. Low POMC/pro-ACTH concentrations make it unlikely that a large pituitary tumor exists in dogs with PDH.  相似文献   
14.
The primary evaluation of ten fungicides for the control of cucumber powdery mildew (Sphaerotheca fuliginea), tomato leaf mould (Cladosporium fulvum) and tomato grey mould (Botrytis cinerea) indicated that nine of them were systemically active against one or more of the pathogens when applied as soil drenches. Benomyl, thiophanate, thiophanate-methyl, thiabendazole and Cela W52A showed activity against all three diseases, but dimethirimol, triarimol and dodemorph were more specific and mainly active against cucumber powdery mildew. An in vitro bioassay generally indicated that fungitoxicity was not translocated from sprayed to unsprayed leaves, and though toxicity to B. cinerea, following soil drenches of benomyl, thiophanate and thiophanate-methyl, was detected by bioassay in leaf sap and calyces it was not detected in fruit. Furthermore, extended evaluation of benomyl for the control of grey mould on cropping tomotoes showed that in the presence of abundant B. cinerea inoculum, benomyl soil drench treatment effectively controlled flower and leaf infection but not fruit ghost-spotting.  相似文献   
15.
16.
The characterisation of selected immune response genes during amoebic gill disease (AGD) in Atlantic salmon, Salmo salar L., was performed using semi-quantitative RT-PCR, quantitative real-time RT-PCR (qRT-PCR), and in situ hybridisation (ISH). The immune response genes of interest were interleukin-1beta (IL-1beta), inducible nitric oxide synthase (iNOS), serum amyloid A (SAA), and serum amyloid P-like pentraxin (SAP). Atlantic salmon were inoculated with the ectoparasite Neoparamoeba sp., the causative agent of AGD, and gill, liver and anterior kidney tissue sampled at 0, 7 and 14 d post-inoculation (p.i.). Semi-quantitative RT-PCR was performed on the tissue samples to identify up/down-regulated mRNA expression relative to uninfected control fish and normalised to the housekeeping gene, beta-actin. Interleukin-1beta (IL-1beta) was the only immune response gene of those investigated whose mRNA was differentially regulated in any of the tissues and was found to be up-regulated in the gills by semi-quantitative RT-PCR. Increased gill IL-1beta mRNA expression was then accurately quantitated and confirmed using probe-based qRT-PCR. The cellular localisation of the IL-1beta mRNA expression in the gills of uninfected and infected fish was then determined by ISH using an IL-1beta-specific biotinylated cRNA probe. Expression of IL-1beta mRNA was localised to filament and lamellar epithelium pavement cells in gills of uninfected and infected Atlantic salmon. These data implicate the involvement of IL-1beta at the site of infection, the gills, of Atlantic salmon during AGD. This work supports previous studies that suggest IL-1beta is important in the regulation of the fish immune response to parasitic infection but additionally shows the cellular localisation of fish IL-1beta mRNA expression during infection.  相似文献   
17.
Over the last decade, the ecosystem services (ESs) framework has been increasingly used to support mapping and assessment studies for sustainable land management purposes. Previous analysis of practical applications has revealed the significance of the spatial scale at which input data are obtained. This issue is particularly problematic with soil data that are often unavailable or available only at coarse scales or resolutions in various part of the world. In this context, four soil-based ecosystem services, namely biomass provision, water provision, global climate regulation, and water quality regulation, are assessed using three conventional soil maps at the 1:1,000,000, 1:250,000 and 1:50,000 scales. The resulting individual and joint ES maps are then compared to examine the effects of changing the spatial scale of soil data on the ES levels and spatial patterns. ES levels are finally aggregated to landforms, land use, or administrative levels in order to try to identify the determinants of the sensitivity of ES levels to change in the scale of input soil data. Whereas the three soil maps turn out to be equally useful whenever ESs levels averaged over the whole 100 km2 territory are needed, the maps at the 1:1,000,000 and 1:250,000 induced biases in the assessment of ESs levels over spatial units smaller than 100 and 10 km2, respectively. The simplification of the diversity and spatial distribution of soils at the two coarsest scales indeed resulted in local differences in ES levels ranging from several 10 to several 100%. Identification of the optimal representation of soil diversity and distribution to obtain a reliable representation of ESs spatial distribution is not straightforward. The ESs sensitivity to scale effect is indeed context-specific, variable among individual ESs, and not directly or simply linked with the soil typological diversity represented in soil maps. Forested and natural lands in the study area appear particularly sensitive to soil data scales as they occupy marginal soils showing very specific ESs signatures.  相似文献   
18.
Anaplasma phagocytophilum is a Gram-negative, obligate intracellular tick-transmitted bacterium that replicates in neutrophils. It causes tick-borne fever (TBF) in sheep and cattle, but also elicits febrile disease in humans as well as in other domestic animals such as dogs, horses, and cats. Although increasingly recognized in Europe, the first laboratory-confirmed case of TBF in cattle from Germany has been published only recently. We here present the unusual case of an intrauterine transmission of A. phagocytophilum in a calf from northern Germany. To our knowledge, this is the first report of such an event occurring under field conditions in cattle.  相似文献   
19.
Varying the crushing parameters in a model mouth apparatus gave different crushed apple samples, which were compared to apples crushed in the human mouth by six people. An image analysis method was developed to measure the similarity between apple particles after crushing in the artificial mouth and in the human mouth. Thus, experimental conditions were determined that produced fruit in a state closest to that obtained after mastication in a human mouth. The influence of these different conditions on the quantity of released volatile compounds was then studied.  相似文献   
20.
A herd is a population structured into groups not all equally in contact, which may influence within-herd spread of pathogens. Herd structure varies among cattle herds. However, published models of the spread of bovine viral diarrhoea virus (BVDV) assume no herd structure or a unique structure chosen as a representative. Our objective was to identify--for different index cases introduced into an initially BVDV--free dairy herd - risky (favourable) herd structures, which increased (decreased) BVDV spread and persistence compared to a reference structure. Classically, dairy herds are divided into calves, young heifers, bred heifers, lactating cows and dry cows. In the reference scenario, groups are all equally in contact. We evaluated the effect of isolating or merging groups. Three index cases were tested: an open persistently-infected (PI) heifer, an open transiently-infected heifer, an immune heifer carrying a PI foetus. Merging all groups and merging calves and lactating cows were risky scenarios. Isolating each group, isolating lactating cows from other groups, and merging calves and young heifers were favourable scenarios. In most structures, the most risky index cases were the following: first, the entry of a PI heifer; second, the birth of a PI calf; last, the entry of a transiently-infected heifer. Recommendations for dairy herds are to raise young animals together before breeding and to isolate lactating cows from others as much as possible. These recommendations will be less efficient if a PI adult enters into the herd.  相似文献   
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