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1.
国内外水产品药物残留检测能力验证比对分析与发展建议 总被引:3,自引:1,他引:2
为进一步促进中国水产品药物残留检测能力验证的发展,提高中国水产品药物残留检测能力验证的水平、促进国际及国内各部委间组织的能力验证互认,笔者概述了国际著名权威机构FAPAS、APLAC及国内CNCA、中国合格评定委员会(CNAS)、中国检科院测试评价中心(ACAS)、农业部等对水产品药物残留检测能力的验证情况,比对分析了中国与国际权威机构在能力验证考核项目、样品制备方法、检测方法要求、结果反馈等方面的差异,并针对中国在水产品药物残留检测能力验证方面存在的问题提出了加强新参数项目研究、丰富样品制备考核手段、改进结果评定方法、加强技术交流等建议,以期为完善中国水产品药物残留检测能力验证活动提供参考。 相似文献
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阐述了江苏里下河地区茭白[Zizania latifolia(Griseb.)Stapf]、莲藕(Nelumbo nucifera Gaertn.Fruct.et Semin.)、芡实(Euryale ferox Salisb.ex DC)和水芹[Oenanthe javanica(Bl.)DC.]等水生蔬菜+克氏原螯虾(Procambarus clarkia Girard)共(轮)作的田间工程、时空耦合农事年历、关键技术及效益分析,为发展生态种养循环农业,转变传统单一种植、养殖方式提供了新思路与技术支撑。 相似文献
4.
采用实地调查的方法对麓湖公园的水生植物资源进行系统分析,结果表明,麓湖公园目前应
用的水生植物共 28 种,隶属于 18 科,其中挺水植物 14 种、浮叶植物 3 种、沉水植物 3 种、耐水湿生
木本植物 8 种;根据观赏部位划分,观花类水生植物有 11 种,花色主要集中在白色、粉色、紫红色、黄
色,多数为顶端花序,花形各异,全年有花可赏;观叶类水生植物有 10 种,叶色不同,叶形各异;观姿
类水生植物有 4 种;麓湖公园的驳岸方式有硬质直立式驳岸和自然斜坡驳岸两种,硬质直立式驳岸以单
一水生植物列植为主,通过水生植物的种类和株高变化丰富景观效果,自然斜坡驳岸以风景林、多种植
物组合配置形式为主,通过耐水湿生木本植物和地被植物种类的变化增加景观的多样性。麓湖公园的水
生植物景观展现出季相变化、色彩搭配和层次效果,若要维持优美的水生植物景观效果,后期的养护管
理非常重要,建议在少游客的游览区域营造以耐水湿生木本植物为主的持久、低养护的水体景观。 相似文献
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Current status of parasitic ciliates Chilodonella spp. (Phyllopharyngea: Chilodonellidae) in freshwater fish aquaculture 下载免费PDF全文
《Journal of fish diseases》2017,40(5):703-715
Freshwater fish farming contributes to more than two‐thirds of global aquaculture production. Parasitic ciliates are one of the largest causes of production loss in freshwater farmed fishes, with species from the genus Chilodonella being particularly problematic. While Chilodonella spp. include ‘free‐living’ fauna, some species are involved in mortality events of fish, particularly in high‐density aquaculture. Indeed, chilodonellosis causes major productivity losses in over 16 species of farmed freshwater fishes in more than 14 countries. Traditionally, Chilodonella species are identified based on morphological features; however, the genus comprises yet uncharacterized cryptic species, which indicates the necessity for molecular diagnostic methods. This review synthesizes current knowledge on the biology, ecology and geographic distribution of harmful Chilodonella spp. and examines pathological signs, diagnostic methods and treatments. Recent advances in molecular diagnostics and the ability to culture Chilodonella spp. in vitro will enable the development of preventative management practices and sustained freshwater fish aquaculture production. 相似文献
7.
Prey partitioning and use of insects by juvenile sockeye salmon and a potential competitor,threespine stickleback,in Afognak Lake,Alaska 下载免费PDF全文
Natura Richardson Anne H. Beaudreau Mark S. Wipfli Heather Finkle 《Ecology of Freshwater Fish》2017,26(4):586-601
Freshwater growth of juvenile sockeye salmon (Oncorhynchus nerka) depends upon the quality and quantity of prey and interactions with potential competitors in the foraging environment. To a large extent, knowledge about the ecology of lake‐rearing juvenile sockeye salmon has emerged from studies of commercially important runs returning to deep nursery lakes, yet information from shallow nursery lakes (mean depth ≤ 10 m) is limited. We examined seasonal and ontogenetic variation in diets of juvenile sockeye salmon (N = 219, 30–85 mm) and an abundant potential competitor, threespine stickleback (Gasterosteus aculeatus; N = 198, 42–67 mm), to understand their foraging ecology and potential trophic interactions in a shallow Alaska lake. This study revealed that adult insects made up 74% of all sockeye salmon diets by weight and were present in 98% of all stomachs in Afognak Lake during the summer of 2013. Diets varied temporally for all fishes, but small sockeye salmon (<60 mm) showed a distinct shift in consumption from zooplankton in early summer to adult insects in late summer. We found significant differences in diet composition between sockeye salmon and threespine stickleback and the origin of their prey indicated that they also separated their use of habitat on a fine scale; however, the two species showed overlap in size selectivity of zooplankton prey. Considering that aquatic insects can be a primary resource for juvenile sockeye salmon in Afognak Lake, we encourage the development of nursery lake carrying capacity models that include aquatic insects as a prey source for sockeye salmon. 相似文献
8.
Utilization of sorghum distillers dried grains in extruded and steam pelleted shrimp diets 下载免费PDF全文
Akinbode A Adedeji Yangen Zhou Xiaoyun Fang Donald A Davis Adam Fahrenholz Sajid Alavi 《Aquaculture Research》2017,48(3):883-898
Use of distillers dried grain with solubles from sorghum (sDDGS) was studied with respect to processing and physicochemical quality of shrimp feed, followed by growth trials with Litopenaeus vannamei (Pacific white shrimp). Shrimp diets with 0%, 10%, 20%, 30% and 40% sDDGS inclusion, as a replacement for soybean meal, were produced using extrusion and steam pelleting. Bulk density of extruded feed (0.53–0.58 g cm?3) was lower than that of pelleted feed (0.61–0.65 g cm?3), although sDDGS level did not have an impact. Finished diets were 100% sinking, with some exceptions in the case of extruded feed. Pellet durability index (89.4–96.3%) had an increasing trend up to 20% and 30% sDDGS for extruded and pelleted diets respectively. Extruded feed had higher degree of gelatinization than pelleted feed, although proportion of gelatinized starch generally decreased with sDDGS level. Water stability (76.2–91.6%) was higher for extruded feed as compared to pelleted feed, and remained unchanged or decreased with sDDGS level. The extruded and pelleted diets were evaluated in two growth trials with L. vannamei for duration of 9 and 6 weeks in 40 and 60 tanks (initial weight 0.36–0.38 g; 10 shrimps per tank) respectively. Significant differences were not observed in final mean weight and survival with respect to sDDGS level, indicating that up to 40% of this novel protein source can be used in feed formulations without affecting the performance of L. vannamei. Comparison of extruded feed with pelleted feed for impact on mean weight and feed conversion ratio did not yield conclusive results. 相似文献
9.
Impact of aquatic acoustic noise on oxidative status and some immune parameters in gilthead sea bream Sparus aurata (Linnaeus, 1758) juveniles 下载免费PDF全文
Francesco Filiciotto Stefano Cecchini Giuseppa Buscaino Vincenzo Maccarrone Giuseppe Piccione Francesco Fazio 《Aquaculture Research》2017,48(4):1895-1903
This study evaluated the ambient noise effect of onshore and offshore aquaculture systems on oxidative status and on some immune parameters in gilthead sea bream (Sparus aurata) juveniles. The experiment was performed for 40 days, projecting two different playlists of acoustic stimuli: offshore aquaculture noise condition that created the typical acoustic field in proximity of an offshore sea cage for fish farming, using a random sequence of quite sea background and boat noises; and onshore aquaculture noise condition that represented the acoustic field inside an open concrete tank for fish farming. A third group without any acoustic projection was used as a control. After 40 days from the beginning of acoustic noise, fish exposed to the offshore aquaculture condition showed significantly higher levels of total oxidant status, lysozyme activity, antiprotease activity and white blood cells together with a lower albumin/globulin ratio in comparison to fish from the control group; whereas fish exposed to the onshore condition showed analytical data placed between the other groups, though never significantly different. These results demonstrate that the offshore aquaculture noise, and in particular the sea soundscape, adversely influences the oxidative status and the immune function of gilthead sea bream determining a mild stress condition that could affect the sea bream welfare. 相似文献
10.
为了解3种常见水生植物对养殖废水中氨氮(NH_3-N)的去除能力,通过模拟试验研究了芦苇(Phragmites australis)、水葫芦(Eichhornia crassipes)、蕹菜(Ipomoea aquatica)对养殖废水中氨氮的净化效果。结果表明,3种供试水生植物对养殖废水中氨氮的净化能力大小为芦苇-水葫芦组合芦苇-蕹菜组合水葫芦蕹菜芦苇。在处理15 d后,供试的3种水生植物对养殖废水中氨氮的净化效率为44.0%~76.5%,而对照组为36%~45%,供试水生植物对养殖废水中氨氮有较强的净化能力。 相似文献