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931.
BACKGROUND: The fire ant, Solenopsis invicta, is one of the most aggressive and invasive species in the world. The trail pheromone Z,E‐α‐farnesene (91% purity) was prepared, and disruption of worker trail orientation was tested using an ethanol‐based aerosol formulation presenting a single puff of this compound by airbrush and compressed air. Trail‐following behaviour was recorded by overhead webcam and ants digitised before and after presentation of the aerosol treatment at four rates (1.6, 16, 160 and 1600 ng cm?2). RESULTS: Ants preferred 110 ng cm?1 over 11, 1.1 and 0.11 ng cm?1 for trail following. Within seconds of presentation of 1600 ng cm?2, the highest dose tested, trail disruption was observed. Disruption was evident as reduced arrival success and reduction in the trail integrity statistic (r2), as well as increased deviation from the trail (deg). The distribution of walking track angles was also flattened. CONCLUSIONS: The feasibility of using aerosol for delivery of trail pheromone was demonstrated, but the need for high purity combined with the difficulty of commercial supply makes this technique impractical. However, the commercial production of Z,E‐α‐farnesene of high purity by industrial biotechnology or from (E)‐nerolidol may be possible in future, which would facilitate further development of trail pheromone disruption of S. invicta. Copyright © 2012 Society of Chemical Industry  相似文献   
932.
The Mekong River system provides a crucial source of natural resources for riparian nations. However, the increasingly rapid pace of hydro‐development in the Mekong Basin is threatening the integrity of the river system, posing a real concern for Lower Basin states, which are particularly dependent on the basin. This scenario has led to warnings of armed conflict, or even ‘water war’, between riparian states. Certainly, the expanding scale of hydro‐development can be expected to continue increasing interstate tensions in the Mekong region; but are these tensions really likely to escalate to armed conflict? This paper explores this question by drawing on the water and conflict theory of Aaron Wolf. Ultimately, this paper concludes that interstate tensions over Mekong hydro‐development are unlikely to generate armed conflict. This is in part due to the strategic impracticality of such a conflict as well as the presence of a river basin management institution. Most compellingly, though, armed conflict is unlikely because the economic imperative shared by Mekong states is better served by cooperation – or at least non‐interference – than conflict, over regional hydro‐development. In closing, the paper urges that the study of water and conflict in the Mekong Basin be refocused at the intrastate level.  相似文献   
933.
There is little information relating to infection control procedures in Australian veterinary practices. This review summarises the findings of international studies in the area of zoonoses and infection control, and discusses potential reasons for the apparent complacency about these issues in veterinary practice. It is the authors’ opinion that legislative changes governing veterinary practice in Australia should be implemented. The curricula in veterinary schools should also emphasise infection control. These measures would significantly improve safety issues associated with the control of zoonoses in veterinary practice.  相似文献   
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936.
Trypanosoma evansi is the most widely spread of the pathogenic African trypanosomes of animals. The disease (surra) was first diagnosed in the Canary Islands in a dromedary camel in 1997; thus, a control plan was implemented achieving the eventual eradication of T. evansi from most of the infected areas in the Archipelago. However, a little area remains still infected despite the use of the same control measures. To evaluate possible reservoirs in the area a representative sample of domestic ruminants was examined by serological, parasitological and molecular tests. Of a total of 1228 ruminants assessed, 61 (5%) were serologically positive (7 cattle, 21 goats, 33 sheep), but T. evansi could be demonstrated in none of them. According to FreeCalc assessment, cattle and goat populations would be free from disease; however, the results from sheep are not adequate to conclude that the population would be free from disease. As a conclusion, surveillance must be exercised on ruminant farms in the surroundings of the infected area in order to evaluate the possible extension of the disease and their potential role as reservoirs of T. evansi.  相似文献   
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938.
Mammary gland problems occur incidentally in horses and one of the rarer conditions is botryomycosis (bacterial pseudomycosis, bacterial granuloma, staphylococcal pseudomycetoma). This article includes a short review of equine mammary gland problems inappropriate lactation, mastitis and neoplasia and botryomycosis, and additionally 2 clinical cases of botryomycosis of the udder resulting from Staphyloccocus aureus infection will be discussed. Both cases involved nonpregnant, nonlactating mares referred for chronic mammary inflammation with draining abcessation. In both mares, botryomycosis caused by S. aureus was confirmed by histopathology and a bacterial culture. Both mares recovered fully after surgical hemimastectomy under general anaesthesia.  相似文献   
939.
Ingestion of food contaminated with slaframine, an alkaloid produced by Rhizoctonia leguminicola, causes a mycotoxicosis, characterised by excessive salivation. Twenty‐eight horses demonstrated this clinical sign after the consumption of alfalfa hay which on inspection showed dark patches on many of the stems. The presence of slaframine (1.5 ppm) in this hay was confirmed by gas chromatography and mass spectroscopy. This is the first equine slaframine toxicosis case reported in Brazil.  相似文献   
940.
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