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OBJECTIVE: To estimate West Nile virus (WNV) infection rates, assess environmental variables that correlated with seropositivity in dogs and cats, and assess whether pets should be considered as possible sentinels for WNV and therefore of potential human exposure. DESIGN: Cross-sectional serosurvey. ANIMALS: 442 dogs and 138 cats. PROCEDURE: Serum samples were screened for seropositivity against WNV by use of the plaque reduction neutralization test. RESULTS: 116 (26%) dogs and 13 (9%) cats yielded positive results. The odds of seropositivity against WNV for outdoor-only family dogs were almost 19 times as great as those for indoor-only family dogs and almost twice as great for stray dogs as for family dogs. Family dogs not receiving heartworm medication were 2.5 times as likely to yield positive results for antibodies against WNV as family dogs receiving heartworm medication. CONCLUSIONS AND CLINICAL RELEVANCE: Seropositivity was greater for outdoor family dogs than for indoor family dogs. Further investigation of the potential use of stray dogs as sentinel indicators for WNV infection and the potential risk of human exposure is warranted.  相似文献   
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OBJECTIVE: To determine concentrations of 2 acute-phase proteins (serum amyloid A [SAA] and lipopolysaccharide-binding protein [LBP]) in serum samples obtained from horses with colic and identify relationships among these acute-phase proteins and clinical data. ANIMALS: 765 horses with naturally developing gastrointestinal tract diseases characterized by colic (ie, clinical signs indicative of abdominal pain) and 79 healthy control horses; all horses were examined at 2 university teaching hospitals. PROCEDURE: Serum concentrations of SAA and LBP were determined by immunoturbidometric and dot-blot assays, respectively. RESULTS: SAA and LBP concentrations were determined for 718 and 765 horses with colic, respectively. Concentrations of SAA were significantly higher in nonsurvivors than in survivors, and horses with enteritis or colitis and conditions characterized by chronic inflammation (eg, abdominal abscesses, peritonitis, or rectal tears) had SAA concentrations significantly greater than those for horses with other conditions. Serum concentrations of LBP did not correlate with outcome, disease process, or portion of the gastrointestinal tract affected. CONCLUSIONS AND CLINICAL RELEVANCE: Circulating concentrations of SAA were significantly higher at admission in horses with colic attributable to conditions having a primary inflammatory cause (eg, enteritis, colitis, peritonitis, or abdominal abscesses) and were higher in horses that failed to survive the episode of colic, compared with concentrations in horses that survived. Serum concentrations of LBP did not correlate with survival. Analysis of these findings suggests that evaluation of SAA concentrations may be of use in identifying horses with colic attributable to diseases that have inflammation as a primary component of pathogenesis.  相似文献   
115.
The behaviours of arteries and veins in the teats of cattle of different age groups is described against the background of general formation and development of the vessels. Growing age was found to have been accompanied by numerical growth of veins (rather than arteries) towards the teat tip and by some thickening of the median vein region. No correlations were established between those vascular changes, on the one hand, and milkability, on the other.  相似文献   
116.
Strains of Pseudocercosporella herpotrichoides collected in France on winter wheat give either fast-growing mycelial colonies with regular margins or slow-growing mycelial colonies with irregular margins. Most of the fastgrowing isolates were sensitive to triadimenol (EC50 below 2mg litre?1), but some of them were resistant to this inhibitor of sterol C-14 demethylation. In contrast, all the slow-growing strains were highly resistant to triadimenol (EC50 greater than 100 mg litre?1). This resistance was also expressed in inhibition of germ-tube elongation. Positive cross-resistance was observed between most of the inhibitors of sterol C-14 demethylation, with the exception of some imidazole derivatives (clotrimazole, prochloraz). All the fast-growing strains were tolerant to fenpropimorph and fenpropidin whereas the slow-growing ones were susceptible; the reverse was true with piperalin and tridemorph. All the field isolates were inhibited to the same extent by the inhibitors of squalene-epoxidase, nafifine and terbinafine. Two types of mutant resistant to triadimenol have been induced under laboratory conditions from sensitive fast-growing strains. The most common mutants were resistant to all the inhibitors of sterol C–14 demethylation and also in some conditions to fenpropimorph, tridemorph and the inhibitors of squalene-epoxidase. The other mutants were characterised by a reduced spectrum of cross-resistance between triadimenol and the other inhibitors of sterol biosynthesis. The field isolates and laboratory mutants resistant to triadimenol and propiconazole were also resistant to each of the four enantiomers of these two fungicides.  相似文献   
117.
OBJECTIVE: To identify and determine the concentrations of phytoestrogens in commercial dog foods. SAMPLE POPULATION: 24 commercial dog foods, including 12 moist or dry extruded commercial dog foods that contained soybeans or soybean fractions and 12 foods without any soybean-related ingredients listed on the label. PROCEDURE: Foods were analyzed for phytoestrogen content, including 4 isoflavones (genistein, glycitein, daidzein, and biochanin A), 1 coumestan (coumestrol), and 2 lignans (secoisolariciresinol and matairesinol) by use of acid-methanol hydrolysis and high-pressure liquid chromatography with UV-absorbance detection. Phytoestrogens were identified and quantified by reference to authentic standards. RESULTS: Isoflavones, coumestans, and lignans were undetectable in diets that did not list soybean-related ingredients on the label. Only 1 of the 12 diets that included soybean or soybean fractions had undetectable concentrations of phytoestrogens and that product contained soy fiber. The major phytoestrogens were the isoflavones daidzein (24 to 615 microg/g of dry matter) and genistein (4 to 238 microg/g of dry matter). CONCLUSIONS AND CLINICAL RELEVANCE: Soybean and soybean fractions are commonly used ingredients in commercial dog foods. Dietary intake of phytoestrogens may have both beneficial and deleterious health effects. Our results indicated that certain commercial dog foods contain phytoestrogens in amounts that could have biological effects when ingested long-term.  相似文献   
118.
Remote sensing techniques have greatly contributed to improve our capacity to observe our environment and its processes. For about 15 years, the use of satellite images for epidemiological purposes has been largely promoted to determine diseases distributions and their variations through time. In some circumstances, when diseases are strongly related to environmental data such as climate, vegetation or land-use, radiation values can be included in prediction models. In other cases, remote sensing data provide information for drawing thematic layers involved in the epidemiological processes, which may differ according to the different ecotypes and ecosystems. According to its final goal, the users can choose from the panel of available radiometers with specific characteristics including spatial resolution and frequency of data. In this paper, two examples of major vector-borne diseases, namely Animal Trypanosomosis and Bluetongue, illustrate these applications.  相似文献   
119.
Small ruminant lentiviruses (SRLV = maedi-visna in sheep and caprine arthritis encephalitis in goats) are distributed throughout most countries of the world, particularly Europe. Laboratories from 16 European countries established collaborations within the framework of a COST (CO-operation in the field of Scientific and Technical Research) action sponsored by the European Union in order to (i) better organize their research programmes on SRLVs and (ii) to coordinate efforts to combat these two diseases. After five years, a consensus conference--the first one in the veterinary medicine field--concluded the work of this network of laboratories by reviewing the present position and discussing three important questions in the field of SRLVs: routes of transmission, consequences of infection and potential role of eradication programmes at either a European or local level, according to the situation in each country or region. This paper brings together existing information regarding these questions and identifies areas for future research.  相似文献   
120.
DNA amplification techniques offer considerable promise for the identification of Mycoplasma mycoides cluster members. They avoid antigenic cross-reactivity and variability that hamper serological methods. Many sets of primers, specific of these different members and of Mycoplasma putrefaciens, have been proposed. To assess the reliability of some of these PCR tests in routine laboratory diagnostic use, 230 field strains supposed to belong to this group were simultaneously identified by PCR and an antigenic method. The results were well correlated to antigenic identification for M. putrefaciens, but PCR failed to identify respectively 74% and 52% of M. mycoides subsp. mycoides Large Colony type and M. capricolum subsp. capricolum strains. Any identification of M. mycoides subsp. mycoides Small Colony type must be confirmed by two different tests. Difficulties in defining the M. species bovine serogroup 7 were also encountered with both the PCR and immunological methods. The occurrence of putative variable antigen(s) on the mycoplasma surface may explain part of the identification difficulties encountered with the immunological methods.  相似文献   
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