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81.
OBJECTIVE: To determine the prevalence of lobomycosis, a mycotic infection of dolphins and humans caused by a yeastlike organism (Lacazia loboi), among dolphins in the Indian River Lagoon in Florida. DESIGN: Cross-sectional study. ANIMALS: 146 Atlantic bottlenose dolphins. PROCEDURE: Comprehensive health assessments of bottlenose dolphins in the Indian River Lagoon of Florida (n = 75) and in estuarine waters near Charleston, SC (71), were conducted during 2003 and 2004. Bottlenose dolphins were captured, examined, and released. Skin lesions were photographed and then biopsied. Tissue sections were stained with H&E and Gomori methenamine silver stains for identification of L. loboi. RESULTS: 9 of 30 (30%) dolphins captured in the southern portion of the Indian River Lagoon had lobomycosis, whereas none of the 45 dolphins captured in the northern portion of the lagoon or of the 71 dolphins captured near Charleston, SC, did. Affected dolphins had low serum alkaline phosphatase activities and high acute-phase protein concentrations. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that lobomycosis may be occurring in epidemic proportions among dolphins in the Indian River Lagoon. Localization of the disease to the southern portion of the lagoon, an area characterized by freshwater intrusion and lower salinity, suggests that exposure to environmental stressors may be contributing to the high prevalence of the disease, but specific factors are unknown. Because only dolphins and humans are naturally susceptible to infection, dolphins may represent a sentinel species for an emerging infectious disease.  相似文献   
82.

Background

The project "Antibiotic resistance in bacteria of animal origin – II" (ARBAO-II) was funded by the European Union (FAIR5-QLK2-2002-01146) for the period 2003–2005, with the aim to establish a continuous monitoring of antimicrobial susceptibility among veterinary laboratories in European countries based on validated and harmonised methodologies. Available summary data of the susceptibility testing of the bacterial pathogens from the different laboratories were collected.

Method

Antimicrobial susceptibility data for several bovine pathogens were obtained over a three year period (2002–2004). Each year the participating laboratories were requested to fill in excel-file templates with national summary data on the occurrence of antimicrobial resistance from different bacterial species.A proficiency test (EQAS – external quality assurance system) for antimicrobial susceptibility testing was conducted each year to test the accuracy of antimicrobial susceptibility testing in the participating laboratories. The data from this testing demonstrated that for the species included in the EQAS the results are comparable between countries.

Results

Data from 25,241 isolates were collected from 13 European countries. For Staphylococcus aureus from bovine mastitis major differences were apparent in the occurrence of resistance between countries and between the different antimicrobial agents tested. The highest frequency of resistance was observed for penicillin. For Mannheimia haemolytica resistance to ampicillin, tetracycline and trimethoprim/sulphonamide were observed in France, the Netherlands and Portugal. All isolates of Pasteurella multocida isolated in Finland and most of those from Denmark, England (and Wales), Italy and Sweden were susceptible to the majority of the antimicrobials. Streptococcus dysgalactiae and Streptococcus uberis isolates from Sweden were fully susceptible. For the other countries some resistance was observed to tetracycline, gentamicin and erythromycin. More resistance and variation of the resistance levels between countries were observed for Escherichia coli compared to the other bacterial species investigated.

Conclusion

In general, isolates from Denmark, England (and Wales), the Netherlands, Norway, Sweden and Switzerland showed low frequencies of resistance, whereas many isolates from Belgium, France, Italy, Latvia and Spain were resistant to most antimicrobials tested. In the future, data on the prevalence of resistance should be used to develop guidelines for appropriate antimicrobial use in veterinary medicine.  相似文献   
83.
Pharmacological conversion of atrial fibrillation (AF) to sinus rhythm in horses can be difficult. The objective of this study was to investigate the feasibility of transvenous electrical cardioversion with custom made catheters in eight horses, of which three had failed cardioversion using quinidine sulfate. Two cardioversion catheters and one pacing/sensing electrode were inserted via the right jugular vein and placed using ultrasound guidance into the left pulmonary artery, the right atrium and the right ventricle, respectively. Because immediate recurrence of AF was encountered in the second horse treated, pre-treatment with amiodarone was given to each of the remaining six horses. Induction of general anaesthesia was associated with dislocation of the cardioversion catheter in three horses, requiring a second catheterisation procedure. During general anaesthesia, biphasic R wave synchronised shocks of up to 360 J were delivered between both cardioversion electrodes. In six horses (75%), including two which had failed quinidine sulfate treatment, sinus rhythm was restored with a mean energy level of 295+/-62 J. No side effects were observed. Blood analysis 3 h after cardioversion revealed normal parameters, including cardiac troponin I values. Transvenous electrical cardioversion of atrial fibrillation with custom made cardioversion catheters can be considered as a treatment option for atrial fibrillation in horses, especially when conventional drugs fail.  相似文献   
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The demand for rice in Eastern and Southern Africa is rapidly increasing because of changes in consumer preferences and urbanization. However, local rice production lags behind consumption, mainly due to low yield levels. In order to set priorities for research and development aimed at improving rice productivity, there is a need to characterize the rice production environments, to quantify rice yield gaps—that is, the difference between average on-farm yield and the best farmers’ yield—and to identify causes of yield gaps. Such information will help identifying and targeting technologies to alleviate the main constraints, and consequently to reduce existing yield gaps. Yield gap surveys were conducted on 357 rice farms at eight sites (19–50 farmers per site) across five rice-producing countries in Eastern and Southern Africa—that is Ethiopia, Madagascar, Rwanda, Tanzania and Uganda—for one or two years (2012–13) to collect both quantitative and qualitative data at field and farm level. Average farm yields measured at the eight sites ranged from 1.8 to 4.3 t/ha and the average yield gap ranged from 0.8 to 3.4 t/ha. Across rice-growing environments, major causes for yield variability were straw management, weeding frequency, growth duration of the variety, weed cover, fertilizer (mineral and organic) application frequency, levelling and iron toxicity. Land levelling increased the yield by 0.74 t/ha, bird control increased the yield by 1.44 t/ha, and sub-optimal management of weeds reduced the yield by 3.6 to 4.4 t/ha. There is great potential to reduce the current rice yield gap in ESA, by focusing on improvements of those crop management practices that address the main site-specific causes for sub-optimal yields.  相似文献   
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