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971.
Two genotypes of bovine viral diarrhoea virus (BVDV) are recognised. Type 2 was first recognised when virulent strains caused significant losses among cattle in North America. Subsequently, BVDV type 2 has been found in many other countries, but recent studies have shown that only type 1 BVDV is circulating in the UK herds (sheep and cattle) with type 1a predominating. During routine genotyping of UK BVDV isolates, a type 2 isolate was identified. Phylogenetic analysis of the 5'-untranslated region of the viral genome showed it to be a BVDV type 2a, most similar to a low virulent US strain of BVDV type 2. Antigenic typing with a panel of monoclonal antibodies verified this classification. This is the first confirmed isolation of BVDV type 2 found circulating in the UK.  相似文献   
972.
Faeces of 484 horses were sampled twice with an interval of 6 weeks while anthelmintic therapy was halted. Faecal eggs counts revealed that 267 (55.2%) horses had consistently low numbers of eggs per gram faeces (EPG) (EPG < 100 or = 100), 155 (32.0%) horses had consistently high EPGs (EPG > 100). Horses with consistently high EPGs were more often mares with access to pasture, aged less than 6 or more than 23 years, that were dewormed at intervals longer than 6 months, and were treated for the last time more than 3 months before the start of the study. Horses with consistently low EPGs were more often male horses with no or limited access to pasture, that were dewormed at maximally 6-month intervals, and were aged between 6 and 23 years. The results are an indication that some horses have consistently low EPGs and perhaps could be used as non-treated animals in a selective anthelmintic treatment scheme aimed at the prevention of the development of anthelmintic resistance.  相似文献   
973.
974.
Tuberculosis infections caused by Mycobacterium (M.) pinnipedii in a South American sea lion, Bactrian camel, and Malayan tapirs kept in two zoological gardens spanning a time period of 5 years are reported. The zoos were linked by the transfer of one tapir. Conventional bacteriological and molecular methods were applied to detect the pathogen. Spoligotyping and MIRU/VNTR-typing performed to assess the genetic similarity revealed identical molecular characteristics of the isolates from all animals involved. Anti-tuberculosis antibodies were detected using ELISA and a recently developed serological rapid test. The study shows that: (i) using molecular methods, the assessment of the genetic relationship of infectious agents helps to confirm the routes of infection, and that (ii) immunological tests may help to detect tuberculosis infections ante mortem more reliably and early. This would prevent the transfer of tuberculosis by asymptomatic animals.  相似文献   
975.
As a result of the growing need for public-health veterinarians, novel educational programs are essential to train future public-health professionals. The University of Minnesota School of Public Health, in collaboration with the College of Veterinary Medicine, initiated a dual DVM/MPH program in 2002. This program provides flexibility by combining distance learning and on-campus courses offered through a summer public-health institute. MPH requirements are completed through core courses, elective courses in a focus area, and an MPH project and field experience. Currently, more than 100 students representing 13 veterinary schools are enrolled in the program. The majority of initial program graduates have pursued public-practice careers upon completion of the program. Strengths of the Minnesota program design include accessibility and an environment to support multidisciplinary training. Continued assessment of program graduates will allow for evaluation and adjustment of the program in the coming years.  相似文献   
976.
Feline upper respiratory tract disease (URTD), mainly caused by feline calicivirus (FCV) and feline herpesvirus, is a major cause of disease outbreaks in feline accommodation such as animal shelters, catteries and multi-cat households. We conducted a longitudinal, yearlong study in five UK feline animal shelters to identify risk factors for the time to diagnosis of URTD. We were especially interested in risk factors that could be identified at the time the cat entered the shelter. Shelter staff recorded data for 1434 cats during 2002–2003. Most of the cats were domestic shorthair cats and were from private households, or were stray or abandoned. Sixty cats without clinical signs of URTD at entry had URTD diagnosed (typically within the first month at the centre). We used two multivariable models: one was a Cox proportional-hazards model, and the other a regression analyses with complementary log–log model.The hazard varied substantially between shelters and was considerably lower for the shelter that had a purpose-built admissions unit with its own isolation facilities. The hazard was greater for purebred cats (HR 4.3–5.0) and for neutered cats (HR 2.0). The hazard was also typically greater if the centre had a greater proportion of cats present with URTD. The analyses suggested that the centre-level risk factors were more important in determining hazard than cat-level risk factors.  相似文献   
977.
978.
Avian influenza is a highly infectious disease in poultry and although the risk of human infection is low, concerns exist that it could evolve into a new human strain of pandemic potential if reassortment with a human influenza virus occurs. In January 2007, the UK government introduced a programme to vaccinate poultry workers to reduce the potential of such an event. This study evaluates the delivery, uptake and costs of the programme in three counties of England. A questionnaire survey was completed by consultants in public health in all the Primary Care Trusts in Norfolk, Suffolk and Cambridgeshire in May 2007. The delivery of the programme varied between Primary Care Trusts, including being delivered in some cases by clinics in primary care, by general practitioners and occupational health services in others. The uptake of vaccination was low ranging from 7% to 29% at a cost of £29 to £132 per person vaccinated. Vaccination of poultry workers as a public health measure to prevent an influenza pandemic is likely to be ineffective with the level of coverage found in this evaluation in our region.  相似文献   
979.
980.
A reliable method was developed to produce a viral antigen preparation from porcine reproductive and respiratory syndrome virus (PRRSV) infected MARC-145 cells by solubilizing the virus with Triton X-100. This method eliminated problems previously encountered with high background reactions associated with PRRSV antigen or cell control antigen. With this new antigen, an indirect enzyme-linked immunosorbent assay (ELISA) was adapted to detect swine serum anti-body against PRRSV. In the ELISA, non-specific reactions associated with test serum samples have been eliminated by utilizing an effective blocking serum diluent. The ELISA is more sensitive than an indirect immunofluorescent assay (IFA), particularly with late-infection sera, while maintaining a high diagnostic specificity. In a comparison of IFA and ELISA using sera collected from 250 pigs of various ages from 5 herds that had PRRS histories, IFA revealed 178 positive samples and 72 negative samples. All of the IFA-positive sera were proven to be ELISA reactors. However, nearly one-half (34/72) of the IFA-negative samples were also ELISA reactors. The diagnostic specificity and sensitivity of the ELISA were 100% and 96.6% with 257 serum samples collected from known healthy PRRS-negative swine herds and 57 sera collected from infected swine at 6 to 56 days after infection, respectively. The ELISA is technically superior to IFA, time-efficient and cost-effective, and suitable for testing of a large number of samples over a short period of time.  相似文献   
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