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41.
We describe the spatial epidemiological features of the 6.8 million meat-juice serological tests that were conducted between 1995 and 2004 as part of the Danish swine Salmonella control programme. We investigated pig and farm density using edge-corrected kernel estimations. Pigs were aggregated at the county level to assess county-level risk, and then we investigated farm-level risk by giving farms a case or non-case label using a cut-off of 40% of pigs positive. Conditional probability surfaces, correcting for the underlying population at risk, were produced for each year of the study period using a novel kernel estimator with a spatially adaptive smoothing bandwidth. This approach improves on previous methods by allowing focussed estimation of risk in areas of high population density while maintaining stable estimates in regions where the data are sparse. Two spatial trends in the conditional probability of a farm being a case were evident: (1) over the whole country, with the highest risk in the west compared to the east; and (2) on the Jutland peninsula with the highest risk in the north and south. At the farm-level a consistent area of risk was the south-west of Jutland. Case farms tended to aggregate indicating spatial dependency in the data. We found no association between pig or farm density and Salmonella risk. We generated hypotheses for this spatial pattern of risk and we conclude that this spatial pattern should be considered in the development of surveillance strategies and as a basis for further, more detailed analyses of the data. 相似文献
42.
Multilocus-sequence typing (MLST) was used to analyse Streptococcus uberis isolates from a single herd associated with long duration (50-260 days) and rapidly cleared (less than 1 month) bovine intramammary infections to determine whether the bacterial type had any impact on the duration of infection. Most chronic infections (24 of 33) were due to continuous infection of the mammary quarter with the same sequence type, and infections were found to persist for many months. The remaining quarters were re-infected with a different sequence type within a single lactation. No particular sequence type or clonal complex (lineage) was associated with persisting infections, indicating that the outcome of intramammary infections with S. uberis is more likely to be dependent on host factors than on inter-strain differences. Analysis of these strains alongside others obtained from the same herd at a later date revealed the shift in the predominant genotypes with time. 相似文献
43.
Infectious bronchitis virus CA99 serotype was isolated from several broiler flocks in Northern California. The virus caused late-onset respiratory disease and increased airsacculitis condemnation in affected flocks despite the use of an established infectious bronchitis virus vaccination program. An experimental study compared Holland/Arkansas and Massachusetts/Arkansas vaccination protocols to determine the efficacy of commercial infectious bronchitis virus vaccines in reducing respiratory disease and airsacculitis lesions found at processing that were associated with a CA99 field isolate. All vaccination groups were given Massachusetts/Connecticut strains of infectious bronchitis virus vaccines at age 1 day followed by vaccination with either Holland/ Arkansas or Massachusetts/Arkansas vaccine strains at 18 days of age. Birds were challenged at age 31 days with a CA99 field isolate. Gross pathology, histopathology, and virus isolation were evaluated. Chickens vaccinated with Holland/Arkansas had marginally better protection against CA99 challenge than chickens vaccinated with Massachusetts/Arkansas, although differences were not statistically significant. 相似文献
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45.
Philippa S. Yam BVMSS Phd Victoria S. Johnson BVSc Henny M. Martineau BVMS Alison Dickie BVMS MVM Martin Sullivan BVMS PhD 《Veterinary radiology & ultrasound》2002,43(2):138-143
A 5-year-old, male German shepherd dog was evaluated for a 5-week history of vomiting, diarrhea, lethargy, and weight loss. In abdominal radiographs, there was an unusual corrugated appearance within a loop of intestine. Sonographically, this loop also had a similar corrugated appearance with alternating hyperechoic and hypoechoic bands. Lymph nodes within the abdomen and thorax were enlarged, and a thoracic mass was also detected. Ultrasound-guided fine-needle aspirates of the mesenteric lymph nodes were highly suggestive of lymphoma. After postmortem examination, a diagnosis of multicentric lymphoma with involvement of the gastrointestinal tract was made. 相似文献
46.
Hansen RA Savage CJ Reidlinger K Traub-Dargatz JL Ogilvie GK Mitchell D Fettman MJ 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(4):457-463
An 18-week feeding trial was performed to investigate the effects of an omega-3 (n-3) fatty acid-enriched ration on plasma fatty acid concentrations and platelet aggregation in healthy horses. Flaxseed oil served as the source of the n-3 fatty acid alpha-linolenic acid (ALA). Twelve horses were fed dietary maintenance requirements using a complete pelleted ration (80%) and timothy grass hay (20%) for a 2-week acclimation period before being randomly assigned either to a treatment (group 1) or control (group 2) group. Group 2 horses (n = 6) were fed the diet described in the acclimation period, whereas group I horses (n = 6) were fed a 10% flaxseed oil-enriched complete pellet (80%) and grass hay (20%). Biological samples and physical measurements were collected at one point during the acclimation period (week 0) and every 4 weeks thereafter (weeks 4, 8, 12, and 16). Body weight, CBC (including platelet count), plasma fibrinogen. electrolyte (Na, K, and Cl) concentrations, and biochemical profile enzyme activities (aspartate aminotransferase, alkaline phosphatase, gamma-glutamyltransferase, and creatine kinase) did not change markedly with diet. Platelet aggregation was not altered by the supplementation of flaxseed oil in these healthy horses, although increases in plasma cis-polyunsaturated 18-carbon fatty acids C18:3; n-3 (ALA) and C18:2; n-6 (linoleic acid), biologically active C20:5; n-3 (eicosapentaenoic acid [EPA]), and malondialdehyde (MDA) were evident. There were no marked decreases in C20:4; n-6 (arachidonic acid [AA]) or increases in C22:6; n-3 (docosahexaenoic acid [DHA]), signifying that flaxseed oil may have had a high percentage of omega-6 (n-6) fatty acids as well as n-3 fatty acids, and this relatively high n-6: n-3 fatty acid ratio may have affected the biochemical effect of n-3 fatty acids. In healthy horses supplemented with flaxseed oil, platelet aggregation was not altered, which may have been due to the limited biologic effect in healthy subjects or the inability of flaxseed oil to induce the necessary biochemical effect of replacing n-6 fatty acids with n-3 types. 相似文献
47.
Pericardial tissue was obtained from 14 dogs with idiopathic pericarditis, and from three dogs with pericardial effusion associated with neoplastic disease, for histopathological assessment and characterisation of infiltrating leucocytes by immunohistochemistry. The major pathological change was extensive pericardial fibrosis which was generally accompanied by a mixed inflammatory response that was of greatest intensity at the cardiac surface of the tissue. Perivascular lymphoplasmacytic aggregates were present at the pleural surface and within the fibrosed pericardium. There were no features that clearly distinguished the samples from dogs with neoplastic disease from dogs with idiopathic pericarditis. The pericardial infiltrates were dominated by MAC 387+ monocyte-macrophages and plasma cells expressing immunoglobulin (Ig)A or IgG. CD3+ T lymphocytes and major histocompatibility complex (MHC) class II+ macrophages were less common, although the perivascular aggregates were mixtures of T and B lymphocytes and a proportion of fibroblasts expressed MHC class II. There was no vascular pathology or deposition of immunoglobulin or complement within vessel walls. These findings are consistent with an immune response dominated by humoral effector mechanisms (Th2 immunity) but do not clearly support a primary immune-mediated pathogenesis for idiopathic pericarditis. 相似文献
48.
49.
Adipose tissue gene expression in obese dogs after weight loss 总被引:1,自引:0,他引:1
Leray V Serisier S Khosniat S Martin L Dumon H Nguyen P 《Journal of animal physiology and animal nutrition》2008,92(3):390-398
Body weight (BW) mainly depends on a balance between fat storage (lipogenesis) and fat mobilization (lipolysis) in adipocytes. BW changes play a role in insulin resistance (IR), the inability of insulin target tissue to respond to physiological levels of insulin. This results in inhibition of lipogenesis and stimulation of lipolysis. Weight gain leads to IR whereas, weight loss improves insulin sensitivity (IS). The aim of this study was to evaluate the effect of weight loss and recovery of IS on the expression of genes involved in lipogenesis and lipolysis in weight losing dogs. Gene expression was studied in both subcutaneous and visceral adipose tissue. Obese dogs received a hypoenergetic low fat high protein diet (0.6 x NRC recommendation). Before and after weight loss, IS was assessed using the euglycaemic hyperinsulinaemic clamp. Gene expression of IRS-2, SREBP, intracellular insulin effectors, ACC, FAS, FABP, ADRP, PEPCK, lipogenesis key proteins, perilipin and HSL, lipolysis key proteins were quantified using real-time RT-PCR in subcutaneous and visceral fat. BW decreased from 15.2 +/- 0.5 to 11.4 +/- 0.4 kg (p < 0.05) over 78 +/- 8 days. When obese, dogs were insulin resistant. After weight loss, IS was improved. In the subcutaneous adipose tissue, the expression of only the IRS-2 was increased. In the visceral adipose tissue, the expression of the genes involved in the lipogenesis was decreased whereas one of the genes implied in the lipolysis did not change. The expression profile of genes involved in lipid metabolism, as measured after weight loss, is indicative for a lower lipogenesis after weight loss than in obese dogs. Our results also confirm dramatic differences in the lipid metabolism of visceral and subcutaneous fat. They should be completed by comparing gene expression during weight losing and normal weight steady state. 相似文献
50.
The development of infectiological diagnostic methodology is characterized by saltatoric, revolutionary leaps. Improved sensitivity and specificity, reduction of analytical sample volumes, increased sample throughput, reduced test complexity associated with improved user friendliness are hallmarks of such developments. Apart from purely technical amenities some innovations also enable conceptual adaptations of monitoring strategies. These include the use of diagnostic assays on-site, e. g. in the stable or in the practice. Selecting the assay which is most "fit-for-purpose" among the plethora of sometimes loudly advertised new technology may be difficult even for the well trained and experienced diagnostician. Standardized licensing procedures for infectiological diagnostic kits may be required to guarantee minimal norms of diagnostic quality. At the same time availability of a diversity of diagnostic kits is needed to broaden the base of diagnostic reliability. New infectiological diagnostic innovations will only be useful if the (expanded) results are transposable to the improved practical care of companion animals and farm animal holdings. In addition, the judgment of results, e. g. for epidemiological plausibility, remains a very important issue even when the test results have been produced by novel high technology diagnostics. 相似文献