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Prapas Patchanee Pakpoom Tadee Orapun Arjkumpa David Love Karoon Chanachai Thomas Alter Soawapak Hinjoy Prasit Tharavichitkul 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(4):529-536
This study was conducted to determine the prevalence of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) in pigs, farm workers, and the environment in northern Thailand, and to assess LA-MRSA isolate phenotypic characteristics. One hundred and four pig farms were randomly selected from the 21,152 in Chiang Mai and Lamphun provinces in 2012. Nasal and skin swab samples were collected from pigs and farm workers. Environmental swabs (pig stable floor, faucet, and feeder) were also collected. MRSA was identified by conventional bacterial culture technique, with results confirmed by multiplex PCR and multi locus sequence typing (MLST). Herd prevalence of MRSA was 9.61% (10 of 104 farms). Among pigs, workers, and farm environments, prevalence was 0.68% (two of 292 samples), 2.53% (seven of 276 samples), and 1.28% (four of 312 samples), respectively. Thirteen MRSA isolates (seven from workers, four from environmental samples, and two from pigs) were identified as Staphylococcal chromosomal cassette mec IV sequences type 9. Antimicrobial sensitivity tests found 100% of the MRSA isolates resistant to clindamycin, oxytetracycline, and tetracycline, while 100% were susceptible to cloxacillin and vancomycin. All possessed a multidrug-resistant phenotype. This is the first evidence of an LA-MRSA interrelationship among pigs, workers, and the farm environment in Thailand. 相似文献
84.
Tharratt RS Case JT Hird DW 《Journal of the American Veterinary Medical Association》2002,220(12):1782-1787
OBJECTIVE:To assess perceptions of state public health officers and state veterinarians in the United States regarding the risks of bioterrorism and determine the degree of support provided for activities related to bioterrorism. DESIGN: Cross-sectional survey. SAMPLE POPULATION: State public health officers and state veterinarians. PROCEDURE: A questionnaire was sent between April and June 2001 to the state public health officer and state veterinarian in each of the 50 states and the District of Columbia. RESULTS: Perceptions of the risk of bioterrorism attacks were similar for state public health officers and state veterinarians. Veterinarians perceived the risks associated with foot-and-mouth disease and Newcastle disease to be higher than did physicians. State veterinarians perceived the risks associated with an anthrax hoax, brucellosis, and ricin toxicosis to be lower than did state public health officers. Risk posed by agents that affected animals exclusively was perceived to be higher than risk posed by agents that affected humans exclusively and zoonotic agents. Number of full-time-equivalent positions devoted to bioterrorism surveillance and percentage of the budget devoted to bioterrorism activities were significantly lower for offices run by state veterinarians than for offices run by state public health officers. State veterinarians were significantly less likely to have knowledge of bioterrorism incidents within their state or district than were state public health officers. CONCLUSIONS AND CLINICAL RELEVANCE: Provision of additional resources to state veterinarians and explicit integration of their expertise and surveillance capabilities may be important to effectively mitigate the risk of bioterrorism. 相似文献
85.
Holt DE Washabau RJ Djali S Dayrell-Hart B Drobatz KJ Heyes MP Robinson MB 《American journal of veterinary research》2002,63(8):1167-1171
OBJECTIVE: To determine whether glutamine (GLN), tryptophan (TRP), and tryptophan metabolite concentrations are higher in cerebralspinal fluid (CSF) dogs with naturally occurring portosystemic shunts (PSS), compared with control dogs. ANIMALS: 11 dogs with confirmed PSS and 12 control dogs fed low- and high-protein diets. PROCEDURE: Cerebrospinal fluid and blood samples were collected from all dogs. Serum and CSF concentrations of GLN, alanine, serine, TRP, 5-hydroxyindoleacetic acid (5-HIAA), and quinolinic acid (QUIN) were measured. RESULTS: Cerebrospinal fluid concentrations of GLN, TRP, and 5-HIAA were significantly higher in PSS dogs, compared with control dogs fed high- or low-protein diets. Cerebrospinal fluid QUIN concentration was significantly higher in PSS dogs, compared with control dogs fed the low-protein diet. Serum QUIN concentration was significantly lower in PSS dogs, compared with control dogs fed either high- or low-protein diets. CONCLUSIONS AND CLINICAL RELEVANCE: An increase in CNS GLN concentration is associated with high CSF concentrations of TRP and TRP metabolites in dogs with PSS. High CSF 5-HIAA concentrations indicate an increased flux of TRP through the CNS serotonin metabolic pathway, whereas high CSF QUIN concentrations indicate an increased metabolism of TRP through the indolamine-2,3-dioxygenase pathway. The high CSF QUIN concentrations in the face of low serum QUIN concentrations in dogs with PSS indicates that QUIN production from TRP is occurring in the CNS. High concentrations of QUIN and other TRP metabolites in the CNS may contribute to neurologic abnormalities found in dogs with PSS and hepatic encephalopathy. 相似文献
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87.
Linda A. Joyce David D. Briske Joel R. Brown H. Wayne Polley Bruce A. McCarl Derek W. Bailey 《Strength and Conditioning Journal》2013,66(5):512-528
Recent climatic trends and climate model projections indicate that climate change will modify rangeland ecosystem functions and the services and livelihoods that they provision. Recent history has demonstrated that climatic variability has a strong influence on both ecological and social components of rangeland systems and that these systems possess substantial capacity to adapt to climatic variability. Specific objectives of this synthesis are to: 1) evaluate options to mitigate greenhouse gas emissions and future climate change; 2) survey actions that individuals, enterprises, and social organizations can use to adapt to climate change; and 3) assess options for system transformation when adaptation is no longer sufficient to contend with climate change. Mitigation for carbon sequestration does not appear economically viable, given the small and highly variable carbon dioxide fluxes of rangeland ecosystems and the high transaction costs that would be incurred. In contrast, adaptation strategies are numerous and provide a means to manage risks associated with climate change. Adaptation strategies are diverse, including altered risk perception by individuals, greater flexibility of production enterprises, and modifications to social organizations that emphasize climatic variability, rather than consistency. Many adaptations represent “no regrets” actions because their implementation can be justified without emphasis on pending climate change. Adaptations specific to livestock production systems can include flexible herd management, alternative livestock breeds or species, innovative pest management, modified enterprise structures, and geographic relocation. Social-ecological systems in which adaptation is insufficient to counter the adverse consequences of climate change might undergo transformative change to produce alternative ecosystem services, production enterprises, and livelihoods. The rangeland profession is in a pivotal position to provide leadership on this global challenge because it represents the intersection of management and scientific knowledge, includes diverse stakeholders who derive their livelihoods from rangelands, and interacts with organizations responsible for rangeland stewardship. 相似文献
88.
Kyle L. Tofflemire R. David Whitley David M. Wong Kenneth R. Waller III Ronald K. Myers Angela E. Pillatzki Gil Ben‐Shlomo 《Veterinary ophthalmology》2013,16(2):149-152
An 11‐year‐old Oldenburg mare presented following three episodes of acute, transient blindness, ataxia, and disorientation within the preceding 7 months. Clinical improvement, including return of vision, occurred within 1 week of initiating corticosteroid therapy for each of the three episodes. However, mild right‐sided miosis was a consistent finding on ophthalmic examinations. Routine clinicopathologic testing revealed no significant abnormalities, and testing of cerebral spinal fluid for selected infectious diseases was unrewarding. Computed tomography of the brain demonstrated a hyperattenuating mass with peripheral mineralization in the rostroventral aspect of each lateral ventricle. The mare was euthanized due to a guarded to poor prognosis. On histopathology, the masses consisted of clusters of cholesterol clefts admixed with leukocytes, mineral deposits, and connective tissue. Cholesterinic granulomas of the lateral ventricles and hydrocephaly were diagnosed. Cholesterinic granulomas should be considered a differential diagnosis in horses presenting for intermittent blindness. 相似文献
89.
Detection and Quantification of Phytophthora ramorum from California Forests Using a Real-Time Polymerase Chain Reaction Assay 总被引:1,自引:0,他引:1
ABSTRACT The timely and accurate detection of pathogens is a critical aid in the study of the epidemiology and biology of plant diseases. In the case of regulated organisms, the availability of a sensitive and reliable assay is essential when trying to achieve early detection of the pathogen. We developed and tested a real-time, nested polymerase chain reaction (PCR) assay for the detection of Phytophthora ramorum, causal agent of sudden oak death. This technique then was implemented as part of a widespread environmental screen throughout California. The method here described is sensitive, detecting less than 12 fg of pathogen DNA, and is specific for P. ramorum when tested across 21 Phytophthora spp. Hundreds of symptomatic samples from 33 sites in 14 California counties were assayed, resulting in the discovery of 10 new host species and 23 infested areas, including 4 new counties. With the exception of a single host, PCR-based discovery of new hosts and infested areas always was confirmed by traditional pathogen isolations and inoculation studies. Nonetheless, molecular diagnostics were key in early pathogen detection, and steered the direction of further research on this newly discovered and generalist Phytophthora species. 相似文献
90.
Rational management of plant diseases, both economically and environmentally, involves assessing risks and the costs associated with both correct and incorrect tactical management decisions to determine when control measures are warranted. Decision support systems can help to inform users of plant disease risk and thus assist in accurately targeting events critical for management. However, in many instances adoption of these systems for use in routine disease management has been perceived as slow. The under-utilization of some decision support systems is likely due to both technical and perception constraints that have not been addressed adequately during development and implementation phases. Growers' perceptions of risk and their aversion to these perceived risks can be reasons for the "slow" uptake of decision support systems and, more broadly, integrated pest management (IPM). Decision theory provides some tools that may assist in quantifying and incorporating subjective and/or measured probabilities of disease occurrence or crop loss into decision support systems. Incorporation of subjective probabilities into IPM recommendations may be one means to reduce grower uncertainty and improve trust of these systems because management recommendations could be explicitly informed by growers' perceptions of risk and economic utility. Ultimately though, we suggest that an appropriate measure of the value and impact of decision support systems is grower education that enables more skillful and informed management decisions independent of consultation of the support tool outputs. 相似文献