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A selection of 43 bovine viral diarrhoea viruses isolated from mainly persistently infected cattle on 23 Slovenian farms between 1997 and 2001 were characterised genetically. Viral RNA was extracted from infected cell cultures, reverse transcribed and amplified by PCR with primers targeting the 5'-UTR and the N(pro) gene, followed by direct sequencing of purified PCR products obtained for both genomic regions. The N(pro) sequences provided the best genetic resolution, and gave also higher statistical support for phylogenetic classification of the viruses. Thirty-eight of the Slovenian isolates were of genetic subtypes 1d and 1f, four were 1b, and one subtype 1g. No BVDV type 2 viruses were found. This genetic prevalence matched those previously reported for neighbouring countries, as opposed to findings reported for more distant European countries, e.g. France, Spain and the UK. From eight cattle herds several virus isolates were analysed; with one exception all isolates from each herd were of the same genetic group. Extended sequencing of the N(pro) and part of the C gene of virus isolates with identical 5'-UTR sequences allowed differentiation between isolates obtained at different times from one herd. 相似文献
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The control of ovine Johne's disease (OJD) is important for domestic trade, the viability of farming units and possibly also for public health. Current strategies in Australia have included quarantine and pasture spelling to decrease prevalence and shedding rates and reduce numbers of Mycobacterium paratuberculosis (Mptb) ingested by susceptible sheep. However, alternative procedures are needed and vaccination with Gudair has recently commenced. This review examines prospects for the control of OJD by chemotherapy, vaccination and mycophages. Current chemotherapeutic regimes for treatment of M. paratuberculosis in ruminants are prohibitively expensive and of dubious efficacy, and apart from environmental concerns, mycophage therapy lacks a track record of success against intracellular bacteria. There is substantial evidence that live and killed mycobacterial vaccines reduce the incidence of clinical disease and shedding rates in OJD. An appraisal of recent experimental results suggests that neonatal vaccination with a defined dose of M. paratuberculosis offers the best prospects for the induction of protective Th1-type immunity. 相似文献
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Tumulty JW Broussard JD Steiner JM Peterson ME Williams DA 《Journal of the American Animal Hospital Association》2004,40(2):120-123
Six dogs were entered into a 30-day, prospective, nonrandomized, uncontrolled clinical trial evaluating the effects of an oral preparation of budesonide on the hypothalamic-pituitary-adrenal (HPA) axis during therapeutic management of active inflammatory bowel disease. Oral budesonide, at a dose of 3 mg/m(2), was administered once daily. Upon entry and completion of the trial, serum basal cortisol, adrenocorticotropic (ACTH)-stimulated cortisol, endogenous ACTH concentration, serum alkaline phosphatase (SAP) activity, and urine specific gravity were evaluated, as well as owner assessment of glucocorticoid-associated side effects. Significant suppression of the HPA axis occurred. No significant differences in SAP activity, urine specific gravity, or owner-subjective assessments were detected. 相似文献
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Eagleman DM 《Science (New York, N.Y.)》2004,303(5661):1144-1146
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