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《Veterinary anaesthesia and analgesia》2022,49(1):104-112
ObjectiveTo verify the efficacy of citral in inducing sedation and anesthesia in silver catfish (Rhamdia quelen) and grass carp (Ctenopharyngodon idella) and to assess the safety of essential oil (EO) of Aloysia citriodora and citral in inducing and maintaining anesthesia in silver catfish.Study designClinical study, randomized, parallel, multi-arm with control group in target species.AnimalsA total of 96 juvenile and 72 adult silver catfish and 80 juvenile grass carp were used.MethodsSilver catfish and grass carp were exposed to different concentrations of citral, 15–675 and 15–600 μL L–1, respectively, during the maximum period of 30 minutes to verify sedation and anesthesia induction and recovery times. In addition, for anesthetic induction, silver catfish were exposed to the EO of A. citriodora and citral at 225 μL L–1 for 3.5 minutes. Then, fish were transferred to an anesthesia maintenance solution at 50 μL L–1 for 10 minutes to assess hematologic and biochemical variables at 60 minutes, 2 and 6 days after treatment.ResultsCitral only induced sedation from 15, 25 and 40 μLL–1 in both species. Anesthesia without mortality was induced in silver catfish at 50–600 μL L–1 and grass carp at 75–450 μL L–1. At 675 and 600 μL L–1, mortality was recorded in silver catfish and grass carp, respectively. The EO of A. citriodora and citral were safe in inducing and maintaining anesthesia in silver catfish, with mean corpuscular hemoglobin concentration being the only variable that varied in relation to time and treatments.Conclusions and clinical relevanceCitral was effective in inducing sedation and anesthesia in both species. In addition, A. citriodora EO and citral were safe in inducing and maintaining anesthesia in silver catfish. Both agents are promising substances for the development of new drugs for fish. 相似文献
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我国渔药的发展概况和安全使用体系建设研究 总被引:1,自引:0,他引:1
介绍了我国渔药的发展概况、渔药使用原则和渔药使用安全体系建设的内容,指出了我国目前渔药使用过程中存在的问题,并提出了相关建议。我国渔药研究是随着鱼病调查和对鱼类病原体研究而开始的。20世纪80年代以前,我国渔药研究偏重于药物筛选、有效浓度、安全浓度、应用范围和给药方法等应用方面,尚未形成商品。20世纪80年代末,随着对细菌性鱼病研究的深入,出现了以鱼服康A型、B型为代表的商品性渔药。渔药科学安全体系建设内容应涵括法规标准制度、渔药管理技术支撑体系、渔药检测及安全评估体系、渔药安全使用和残留监控等。 相似文献
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Linking spatial pattern of bottom fish assemblages with water masses in the North Sea 总被引:2,自引:0,他引:2
Understanding the links between large scale spatial structuring of fish assemblages and shaping factors is essential to develop comprehensive ecosystem-based fisheries management. In this study, we investigated spatial patterns of bottom fish assemblages in the North Sea in relation to prevailing water masses in the region. We based our analysis on catch data from the German Small-Scale Bottom Trawl Survey conducted between 1987 and 2005 and used both ordination techniques and Mantel tests. Spatial variability of bottom fish assemblages was larger than inter-annual variability. Five significantly different bottom fish assemblages were associated with the following prevailing hydrographical regimes: i) the English Channel, ii) Continental Coastal, iii) central North Sea, iv) northern North Sea, and v) northern Atlantic water masses. Associations were generated by gradients in relative proportions of abundant species such as grey gurnard ( Eutrigla gurnardus ), dab ( Limanda limanda ), whiting ( Merlangius merlangus ), haddock ( Melanogrammus aeglefinus ) and Norway pout ( Trisopterus esmarki ). Taking into account large scale spatial structuring of catch data Mantel tests confirmed significant correlation between the fish assemblages and hydrographical variables. In summary, our results strongly support the hypotheses that hydrographical features such as water masses, fronts, and residual currents could shape bottom fish associations in the North Sea. Spatial demarcations of bottom fish assemblages indicated by this study can be used to support ecosystem-based fisheries management strategies. 相似文献
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Abstract – The native and non-native freshwater fish species richness as well as the proportion of native fish species to overall fish species were examined to test a hypothesis of a spatial linkage between the distributions of dams and non-native fishes based on survey data collected in rivers and streams in Hokkaido, Japan. Non-native fish species have steadily increased in Hokkaido since the mid 1970s, as indicated by the decreasing proportion of native fish species per fish survey. Non-native species richness was significantly higher in areas above dams (i.e., reservoirs and their inlet streams) compared to areas without dams. As a result, the proportion of native fish species was lower above dams. This proportion was lower in developed and agricultural areas compared with forest areas, although both native and non-native species richness were higher in areas with development and agriculture. Non-native cyprinids, catfish and snakehead occurred primarily in a particular river basin with the largest drainage area, the longest history of reclamation and highest human population in the island. Non-native salmonids on the other hand, occurred in forest areas at higher elevations and their occurrence was associated with the existence of dams. There was a spatial linkage between the distribution of dams and non-native species, although it was applicable only to salmonids. The management of dams and reservoirs needs a strategy to prevent further expansion of exotic salmonids such as rainbow and brown trout. These species can be a significant threat to native Japanese salmonids as a result of various biological mechanisms. 相似文献