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101.
Alvin A. Gajadhar Edoardo Pozio H. Ray Gamble Karsten Nöckler Charlotte Maddox-Hyttel Lorry B. Forbes Isabelle Vallée Patrizia Rossi Albert Marinculić Pascal Boireau 《Veterinary parasitology》2009,159(3-4):197-205
Because of its role in human disease, there are increasing global requirements for reliable diagnostic and control methods for Trichinella in food animals to ensure meat safety and to facilitate trade. Consequently, there is a need for standardization of methods, programs, and best practices used in the control of Trichinella and trichinellosis. This review article describes the biology and epidemiology of Trichinella, and describes recommended test methods as well as modified and optimized procedures that are used in meat inspection programs. The use of ELISA for monitoring animals for infection in various porcine and equine pre- and post-slaughter programs, including farm or herd certification programs is also discussed. A brief review of the effectiveness of meat processing methods, such as freezing, cooking and preserving is provided. The importance of proper quality assurance and its application in all aspects of a Trichinella diagnostic system is emphasized. It includes the use of international quality standards, test validation and standardization, critical control points, laboratory accreditation, certification of analysts and proficiency testing. Also described, are the roles and locations of international and regional reference laboratories for trichinellosis where expert advice and support on research and diagnostics are available. 相似文献
102.
103.
OBJECTIVE: To assess the effect of interferon (IFN)-alpha on viability of feline corneal epithelial cells, replication of feline herpesvirus (FHV)-1, and virus-induced cytopathic changes. SAMPLE POPULATION: Healthy eyes from 10 recently euthanatized cats. PROCEDURE: 4 replicate primary cultures of feline corneal epithelial cells were grown after the addition of 10(2) to 10(6) IU of IFN-alpha/mL. Cultures were examined every 24 hours for evidence of cytotoxic changes. Viable cell counts and percentage of viable cells were determined 48 hours after initiation of culture. In a separate experiment, cultures of corneal cells were inoculated with FHV-1 and cultured for 72 hours with or without 10(5) IU of IFN-alpha/mL. The FHV-1-infected cultures were evaluated for viral-induced cytopathic effects, and viral titers were determined in samples of culture supernatant. RESULTS: Interferon-alpha did not have cytotoxic effects on corneal epithelial cells at concentrations ranging from 10(2) to 10(6) IU of IFN-alpha/mL. Interferon-alpha at a concentration of 10(5) IU/mL significantly reduced the cytopathic changes and FHV-1 titers. CONCLUSIONS AND CLINICAL RELEVANCE: Lack of in vitro cytotoxic effects and efficacy against FHV-1 infection in primary cultures of feline corneal cells suggests that the in vivo therapeutic effect of IFN-a should be assessed in controlled clinical trials. 相似文献
104.
Deutz A Fuchs K Schuller W Nowotny N Auer H Aspöck H Stünzner D Kerbl U Klement C Köfer J 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(7-8):306-311
The aim of this study was to investigate the seroprevalences to zoonotic pathogens in hunters, to propose preventive measures and to obtain more information about the occurrence of zoonotic pathogens in local wild animal populations. From 146 male and 3 female hunters originating from the south-eastern Austrian federal states of Styria and Burgenland blood samples were taken and anamnestic data were obtained using a questionnaire. The serological investigations included the following viral, bacterial and parasitic zoonotic agents or zoonoses, respectively (antibody-seroprevalences in brackets): encephalomyocarditis virus (EMCV, 15%), Puumala-Hantavirus (10%), Newcastle Disease virus (NDV, 4%), borreliosis (IgG 42%, IgM 7%), brucellosis (1%), chlamydiosis (3%), ehrlichiosis (IgG 15%, IgM 3%), leptospirosis (10%), tularaemia (3%), Q fever (0%), Echinococcus multilocularis/E. granulosus (5%/11%), toxocariasis (17%). Out of a control group of 50 persons (urban population, no hunters) only one person was found to be seropositive for Toxocara canis and NDV and four for EMCV, all other results were negative in the control group. The high seroprevalences especially to Borrelia burgdorferi s.l., Ehrlichia spp., Leptospira interrogans, E. granulosus, E. multilocularis, encephalomyocarditis virus and Puumala virus demonstrate that hunters are particularly exposed to zoonotic pathogens. It should also be noted that one hunter was seropositive for Brucella abortus and five exhibited antibodies to Francisella tularensis. In these cases, as well as in the cases of the 15 seropositives for Leptospira interrogans, the suspected source of infection may--besides rodents--also include wild boars and brown hares. The infections with NDV and Chlamydophila psittaci may be traced back to contact with certain species of birds (potential risk: aviaries). For Hantaviruses, rodents are considered to be the main source of human infections. 相似文献
105.
A cross-sectional study was conducted with 617 finishing pigs aged 10–25 weeks in 11 commercial herds of different health statuses as defined by the Danish monitoring program for specific-pathogen-free (SPF) herds. A standard clinical examination was performed and a blood sample was obtained from each pig for determination of haptoglobin concentration in serum.
Pigs aged 10–14, 15–19 and 20–25 weeks in conventional herds had higher haptoglobin concentrations than high-health SPF (SPF-x) pigs of the same age. There was no significant difference between SPF-x pigs of different ages. Conventional pigs aged 15–19 and 20–25 weeks had higher haptoglobin concentrations than conventional pigs aged 10–14 weeks. Herd influenced the haptoglobin concentration. Lame pigs and pigs with tail or ear bite had elevated haptoglobin concentrations. No significant effect of respiratory symptoms or umbilical hernia was found. 相似文献
106.
Investing in water for food, ecosystems, and livelihoods: An overview of the comprehensive assessment of water management in agriculture 总被引:1,自引:0,他引:1
Charlotte de Fraiture David Molden Dennis Wichelns 《Agricultural Water Management》2010,97(4):495-501
The authors of the recently completed Comprehensive Assessment of Water Management in Agriculture (CA) concluded that there are sufficient water resources to produce food for a growing population but that trends in consumption, production and environmental patterns, if continued, will lead to water crises in many parts of the world. Only if we act to improve water use will we meet the acute fresh water challenge. Recent spikes in food prices, partially caused by the increasing demand for agricultural products in non-food uses, underline the urgent need to invest in agricultural production, of which water management is a crucial part. The world experienced similar pressure on per capita food supplies and food prices in the 1960s and 1970s, but the challenges now are different than those we experienced 50 years ago. The world's population is substantially larger, there are many more people living in poverty, and the costs of many agricultural inputs are much higher. The current situation and the long-term outlook require a fresh look at approaches that combine different elements such as the importance of access to water for the poor, providing multiple ecosystem services, rainwater management, adapting irrigation to new needs, enhancing water productivity, and promoting the use of low-quality water in agriculture. This special issue highlights the analysis behind a number of policy options identified by the CA, a five-year multi-disciplinary research program involving 700 scientists. This introductory article sets the background and context of this special issue, introduces the key recommendations from the CA and summarizes the papers in this issue. 相似文献
107.
Satisfying future water demands for agriculture 总被引:2,自引:0,他引:2
The global demand for water in agriculture will increase over time with increasing population, rising incomes, and changes in dietary preferences. Increasing demands for water by industrial and urban users, and water for the environment will intensify competition. At the same time, water scarcity is increasing in several important agricultural areas.We explore several pathways for ensuring that sufficient food is produced in the future, while also protecting the environment and reducing poverty. We examine four sets of scenarios that vary in their focus on investments in rainfed agriculture and irrigation, and the role of international trade in adjusting for national disparities in water endowments. Rainfed agriculture holds considerable potential but requires adequate mechanisms to reduce inherent risks. Irrigation expansion is warranted in places where water infrastructure is underinvested such as sub-Saharan Africa. In South Asia the scope for improving irrigation performance and water productivity is high. International trade can help alleviate water problems in water-scarce areas, subject to economic and political considerations. We examine also a regionally optimized scenario that combines investments in rainfed and irrigated agriculture with strategic trade decisions. Compared to ‘business as usual’, this scenario reduces the amount of additional water required to meet food demands by 2050 by 80%. Some of that water could be made available for the environment and other sectors. We conclude that there are sufficient land and water resources available to satisfy global food demands during the next 50 years, but only if water is managed more effectively in agriculture. 相似文献
108.
Harvey Tyler‐Walters Stuart I. Rogers Charlotte E. Marshall Keith Hiscock 《水产资源保护:海洋与淡水生态系统》2009,19(3):285-300
- 1. Methods of sensitivity assessment to identify species and habitats in need of management or protection have been available since the 1970s.
- 2. The approach to sensitivity assessment adopted by the Marine Life Information Network (MarLIN) assumes that the sensitivity of a community or biotope is dependent on the species within it. However, the application of this approach to sedimentary communities, especially offshore, is complex because of a lack of knowledge of the structural or functional role of many sedimentary species.
- 3. This paper describes a method to assess the overall sensitivity of sedimentary communities, based on the intolerance and recoverability of component species to physical disturbance. A range of methods were applied to identify the best combinations of abundant, dominant or high biomass species for the assessment of sensitivity in the sedimentary communities examined.
- 4. Results showed that reporting the most frequent species' sensitivity assessment, irrespective of the four methods used to select species, consistently underestimated the total sensitivity of the community. In contrast, reporting the most sensitive assessment from those species selected resulted in a range of biotope sensitivities from very low to very high, that was better able to discriminate between the sensitivities of the communities examined.
- 5. The assumptions behind the methodology, its limitations and potential application are discussed.
109.
110.
Charlotte Vogel 《Genetic Resources and Crop Evolution》1963,11(1):295-332
Zusammenfassung Das Wachstum von Erbsenkeimlingen wird durch Einwirkung harter Röntgenstrahlen (ab 800 r) gehemmt, ein sofortiger Wachstumsstillstand trat auch bei höheren Dosen nicht ein. Die größte Strahlungsempfindlichkeit besitzt dabei die Wurzelmeristemzone.Bestrahlungsversuche (15–20 kr) ergaben bei mit Bleisalz vorbehandelten und nicht vorbehandelten Erbsensamen starke Schädigungen; gequollenes Saatgut ist empfindlicher als lufttrockenes. Gewächshaus- und Freilandversuche zeigen, daß sich bereits eine Dosis von 4 kr keimungs- und entwicklungshemmend auswirkt, stärkere Dosen hatten auch eine Hemmung des Wurzelwachstums zur Folge. Eine Sensibilisierung durch Bleisalzvorbehandlung des Saatgutes ist unbedeutend oder nicht nachweisbar. Unterschiede in der Wirksamkeit zwischen harter und mittelharter Strahlung sind nicht eindeutig festzustellen.
Summary The growth of pea seedlings is inhibited by the influence of hard X-rays (800 r and more). However a sudden growth stop does not happen even by application of higher doses. The most sensible zone against radiation lies within the root meristem. — Radiation experiments (15–20 kr) yielded serious damages in pea seeds, the effect being the same in by lead salts prepared seeds and in unprepared seeds. Soaked seeds are more sensible than dry ones. Experiments in the green house and in the field prove that already a dose of 4 kr is inhibiting the germination and plant development, higher doses effect also an inhibition of the root development. A sensibilization by preparation with lead salts is hardly or not at all to be proved. Differences in the effectivity between hard and middle hard radiation are not distinctly to be observed.
( 800), . . (15 000–20 000p) ; — . , 4000 ; . , . .相似文献