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51.
Veterinary surgeons have a long tradition of consulting one another about problem cases and many have unwittingly practised telemedicine when discussing cases by telephone or by sending laboratory reports by telefax. Specific veterinary telemedicine applications have been in use since the early 1980s, but little research has been undertaken in this field. The Pubmed and CAB International databases were searched for the following Boolean logic-linked keywords; veterinary and telemedicine, veterinary and telecare, animal and telemedicine, animal and telecare and veterinary and e-mail and an additional search was made of the worldwide web, using Google Scholar. This returned 25 papers which were reviewed. Of these only 2 report research. Sixteen papers had no references and 1 author was associated with 13 papers. Several themes emerge in the papers reviewed. These include remarks about the use of telemedicine, the benefits that can and are derived from the use of telemedicine, areas of practice in which telemedicine is being used, ethical and legal issues around the practice of telemedicine, image standards required for telemedicine, the equipment that is required for the practice of telemedicine, advice on ways in which digital images can be obtained and educational aspects of telemedicine. These are discussed. Veterinary practice has lagged behind its human counterpart in producing research on the validity and efficacy of telemedicine. This is an important field which requires further research.  相似文献   
52.
Arbuscular mycorrhizal fungi (AMF) play an important role in plants growth and soils dynamic in all most ecosystems. The main objective of the present study was to evaluate the plant-AMF interactions on soil functions under arid protected area ‘Zarat-Gabès’ in Tunisia.

AMF colonization was evaluated by visual observation of AMF in fine roots of eight herbaceous plants. The level of mycorrhizal colonization varied between plants. Astragalus corrugatus and Hippocrepis areolata showed the highest mycorrhizal performance. The relative spore number was significantly different across rhizosphere soils. Statistical analysis showed a clearly positive correlation between the number of spores and plant-mycorrhizal intensity.

For microbiological parameters, our results showed that mycorrhizal plants improved significantly the various microbiological parameters. Rhizosphere soils of Astragalus corrugatus and Hippocrepis areolata presented the necessary microbial densities and microorganisms more stable compared to unplanted soil. This study allowed obtaining a new result that challenges us about the need for efficient management of natural resources in the objective of nature conservation.  相似文献   

53.
Control of IBR and BVD should be possible in Europe. Effective vaccines and reliable tools for monitoring are available. Systematic approach and strict implementation of control measures are essential. Voluntary or mandatory programs are ongoing on regional or national level in a lot of countries. Successful programs put pressure on surrounding regions/countries to initiate control program as well.  相似文献   
54.
In a cattle herd problems were noticed during 1.5 years, characterised by emaciation and loss of milk production with lower fat- and protein%, tenesmus, central nervous symptoms (aggression, circling and blindness), diarrhoea, eczema solare and death. Clinical, laboratory and post mortem examinations did not reveal a specific cause at first. An intoxication was suspected based on the clinical symptoms, the course of the disease in sick animals and severe liver cirrhosis found in a sudden death cow: The animals were fed grassilage derived from an air force base on which an overwhelming amount of tansy ragwort (Senecio jacobaea) was present. On subsequent microscopic examination of the livers of 11 slaughtered clinically healthy animals all of these showed fibrosis in varying extension. Cirrhosis and fibrosis of the liver and the clinical symptoms are all features of chronic pyrrolyzidine alkaloidosis. Tansy ragwort poisoning has not been diagnosed in the Netherlands for years. The rise in cases is due to more extensive use of land.  相似文献   
55.
56.
An experiment was performed to develop a model to study the impact of stress on responsiveness to infection with bovine herpesvirus 1 (BHV1) in veal calves. Social isolation after previous group-housing was used as a putatively stressful treatment. Group-housed specific pathogen-free veal calves (n=8) were experimentally infected with BHV1 at the age of 12 weeks. Half of the calves were socially isolated at the time of infection. Clinical, virological and serological responses to BHV1, and adreno-cortical reactivity to exogenous ACTH were examined. In comparison with group-housed calves, calves socially isolated at the time of infection showed a diminished clinical and fever response, and delayed viral excretion after primary infection with BHV1. Four weeks after social isolation, basal cortisol levels before, and the integrated cortisol response after administration of a low dose of ACTH, were significantly depressed in socially isolated calves. The results suggest that social isolation in veal calves influences the response to an experimental BHV1 infection. A possible mechanism is discussed.  相似文献   
57.
We examined whether antibodies against bovine herpesvirus (BHV) 5 cross-react with BHV1 antigens and whether they could interfere with BHV1 eradication programmes. Six calves were experimentally infected with different doses of BHV5 strain N569; homologous antibodies were first detectable on day 11 post infection; they cross-reacted in a BHV1 virus neutralisation test, in a BHV1-glycoprotein (g)-B blocking ELISA and in a BHV1-gE ELISA, but not in a BHV1-gE blocking ELISA. This study indicates that, in ongoing BHV1 eradication programmes, based on vaccines that lack gE, BHV5 infections may not lead to false-positive serological reactions in case cattle are tested for BHV1-gE antibodies by the BHV1-gE blocking ELISA; antibodies against BHV5 may be differentiated from antibodies against BHV1. The BHV1-gE blocking ELISA may, therefore, offer opportunities for the serological differentiation between BHV1 and BHV5 infections.  相似文献   
58.
Myrtus communis L. (Myrtaceae), in Tunisia, is closely associated with Quercus suber L. forest which stretched continuously from the North to parts of Cap Bon and Tunisian Dorsal. The destruction of the primary oak forests associated to an over-exploitation of Myrtus for its essential oil quality had led to discontinuous populations exhibiting various levels of degradation. Using starch gel electrophoresis, we analyzed the polymorphism of nine isozymes in order to assess genetic diversity and structuring of 17 natural populations prospected in the three geographical regions and coinciding with subhumid, humid inferior and semi-arid superior bioclimates. The analysis of the level and the distribution of the genetic diversity in this species might help in its conservation. Out of the 18 loci detected for all populations and isozymes analyzed, 12 loci were polymorphic. Allelic frequencies differed according to populations and particular alleles characterized ecological groups. A high level of genetic variation within populations was observed. The mean number of alleles per polymorphic locus was Ap = 1.67, the percentage of polymorphic loci was P = 60.3% and the observed (Ho) and the expected (He) heterozygosities were respectively 0.144 and 0.215. Populations belonging to subhumid (Cap Bon) and semi-arid superior (Tunisian Dorsal) climates, located in degraded sites exhibited the highest level of inbreeding (0.425 < FIS < 0.450). A high level of differentiation (FST = 0.396) and a low gene flow (Nm = 0.337) among populations, as a result of habitat intermediate destruction, were revealed. The differentiation of populations within the same bioclimate (or geographic) group was substantial and relatively higher for semi-arid superior populations (FST = 0.262), which were more distant. The three ecological groups exhibited a high level of structuring (FST = 0.401). These differentiations might be due to geographic distances and to the variations of ecological factors between sites, including human activities and environmental factors. Nei’s (1972) genetic distances calculated between pairs of populations were globally low (0.006 < D < 0.367) with a mean of 0.15. They indicate a high level of similarity between populations. UPGMA clustering, established through Nei’s genetic distances, showed three population aggregates according to their geographic/bioclimatic appartenances. The high differentiation between populations and the low level of their genetic divergence indicated their recent isolation under anthropic pressures. The species conservation (in situ or ex situ) strategies should take into account the genetic diversity level within populations and its variation between geographic groups.  相似文献   
59.
The objectives of this study, conducted in Bou‐Hedma National Park, were to quantify the effects of the dominant legume Acacia tortilis subsp. raddiana on soil properties. Three sites with differing soil texture were studied; the first with a gravelly‐sand texture, the second with a sandy‐loam texture and the third with a loam texture. At each study site, two subhabitats were distinguished, under Acacia canopies (canopied soil) and open areas (uncanopied soil). Soil organic carbon, microbial biomass and microbial coefficient were found to be significantly greater in canopied soil, compared with uncanopied soil. The lower metabolic quotient under this legume indicated a higher carbon use efficiency of microorganisms in soil. The enzyme activities (dehydrogenase, phosphatase and β‐glucosidase) expressing soil microbial activity were significantly higher under Acacia canopies. Therefore, A. raddiana planting can be considered an effective and applicable measure to restore vegetation and control desertification in arid regions. On account of the variability of soil texture in the park, three sites were studied: gravelly‐sand, sandy‐loam and loam soils. The highest microbial density and activity were registrated in sandy‐loam soil. Microbial biomass and activity increased gradually and significantly to a maximum at 20–30 cm and subsequently decreased at 30–50 cm. The results allow us to conclude that soil texture and soil depth can play an important role in the extent of soil properties. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
60.
Ability to detect Pseudocercospora macadamiae infection in macadamia husk at least four months before symptoms become visible will aid the development of disease control measures. This study examined the distinctness of P. macadamiae within the phylogenetic lineages of the genus Pseudocercospora. In addition, we developed two quantitative PCR (qPCR) assays, as rapid diagnostic tools, for early detection and quantification of P. macadamiae in planta. Phylogenetic analysis of concatenated sequences of four gene loci (large subunits, internal transcribed spacer (ITS), translation elongation factor 1-alpha (TEF-1α) and actin of 47 P. macadamiae isolates showed that P. macadamiae is a distinct species in the genus Pseudocercospora. P. macadamiae isolates were partitioned into subunits in the cluster but the grouping of the isolates was regardless of location. Nucleotide diversity (0.02) and the coefficient of genetic differentiation (0.07) were low in the P. macadamiae population. Two qPCR primer sets, based on ITS (PMI) and TEF-1α (PME) were designed that consistently amplified P. macadamiae in fungal cultures (Ct = 16.93 ± 0.11 and Ct = 21.20 ± 0.11, respectively) and in planta (Ct = 32.36 ± 0.28 and Ct = 38.07 ± 1.20, respectively). The PMI primers also detected species in the genus Pseudocercospora, while PME was more specific and robust for quantification of P. macadamiae. Both primer sets detected P. macadamiae in asymptomatic tissue samples and strongly differentiated various stages of disease progression, which revealed approximately 10-fold increase in fungal biomass between each consecutive stage of symptom development.  相似文献   
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