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Ellis JA Waldner CL McIntosh KA Rhodes C Harding JC Ringler SS Krakowka S 《American journal of veterinary research》2006,67(11):1890-1894
OBJECTIVE: To determine the prevalence of antibodies against a swine-origin Helicobacter pylori-like organism (HPLO) and H pylori in conventionally reared swine. ANIMALS: 640 conventionally reared swine of various ages from 16 high-health farms in Canada, 20 sows from Ohio, and 35 gnotobiotic swine. PROCEDURES: Blood was collected from the cranial vena cava. Sera were collected and tested via ELISA for antibodies against antigen prepared from a swine-origin HPLO and human H pylori strain 26695. RESULTS: Antibodies reactive with a swine HPLO, H pylori, or both were detected in 483 of 640 swine from all 16 farms in western Canada. Seroprevalence varied with age and was low (5.6%) in suckling ( 4 weeks old to adulthood. CONCLUSIONS AND CLINICAL RELEVANCE: Findings suggested that colonization by a swine-origin HPLO, H pylori, or both and resultant seroconversion, like that of H pylori infection in humans, were common in commercial swine operations. Furthermore, data indicated that gastric infection was acquired at an early age. The relationships to gastric colonization by HPLOs and clinical manifestations of disease such as gastritis and gastroesophageal ulceration remain to be determined. 相似文献
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Concerns exist that some uses of antimicrobials in cattle may lead to the emergence, proliferation, dissemination and persistence of resistant pathogenic bacteria in animal agriculture, which in turn can infect humans via the food supply. The degree of perceived risk varies with the clinical indication for which the antimicrobial in question is used. In this study, four uses of antimicrobials are considered, including in acutely sick, chronically sick, at-risk, and high-risk cattle, contrasting the degree of risk among these uses. Using a random sample of 103 feedlot cattle veterinarians and variables drawn from the theory of planned behavior, we predict differences in risk perception by clinical indication with differences in perceived efficacy of antimicrobials, social pressures to use antimicrobials, and moral obligations to use antimicrobials. In most models, veterinarians who perceived that others in the feedlot industry (i.e., other feedlot veterinarians, nutritionists, feedlot clients, and retained owners of cattle) were more likely to expect them to use antimicrobials in one situation versus another, the less likely those veterinarians perceived the risk of antimicrobial risk to be greater in the former versus the latter situation. Only two of these contrasts contained influences outside the immediate feedlot relationships. This exception involves the 'downstream' public: meat packers, retailers, and consumers. Veterinarians who believe that using antimicrobials for acutely sick cattle is more beneficial than using antimicrobials for chronically sick cattle were more likely to believe that antimicrobial resistance was a less probable outcome in acutely sick cattle than in chronically sick cattle. 相似文献
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