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小型中上层鱼类和低值商品鱼类的加工是当前世界各渔业国家在实践中面临的现实问题,有待于解决。为了解决面临的实际问题,近几年来只本研制了新加工法,并正探索鱼类加工设备的新设计方法。其中,建造了解冻器试样,利用超声波水压力原理作为其工作的基础,有利于解冻速度增加一倍。试样在试验时解冻200公斤鱼不到30分钟。解冻时使用的超声波对管理人员和解冻对象都没有不利的影响。鱼类分类机在改变成倾斜安装的滑轮对 相似文献
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防城港人工礁区内5种恋礁鱼类的声学标志跟踪 总被引：2，自引：1，他引：1
为了解人工鱼礁区鱼类的活动特点及使用超声波遥测方法进行人工鱼礁区鱼类研究的可行性, 2017年7月7日至9月8日于防城港人工鱼礁区利用Vemco定位系统(Vemco position system, VPS)对5种北部湾沿海常见的野生恋礁性鱼类共9尾[体长(21.7±3.8) cm,体重(314±186) g]进行超声波标志遥测跟踪。结果表明, 9尾鱼中的3尾定位效果较为理想(1749～9591个定位结果),活动范围较小,其中100%最小凸多边形(minimum convex polygon, MCPs)范围为12687.6～17123.2 m^2。而50%和95%核心利用分布(Kernelutilizationdistribution,KUDs)范围为5788.1～8708.9 m^2和10240.5～16463.7 m^2。另6尾鱼未取得理想的定位效果(0～14个定位结果),接收机接收回的定位数据可以被检测,表明鱼依然在礁区附近活动。在游离检测范围28～51 d后又有信号返回,说明样本鱼对人工鱼礁环境有一定的偏好性,研究期间样本鱼表现出一定的活动深度变化规律,在15:00～22:00时段活动深度相对较浅,主要集中于人工鱼礁礁体上方(距水底5 m以上)。研究表明,应用超声波遥测技术可以了解鱼类在自然生活状态下的活动特点,可作为鱼类研究的有效手段加以应用。 相似文献
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采用不同强度的超声波处理,研究鱼类免疫效应和疫苗导入效果,从而优化最适超声波处理强度,以便应用于渔业实践中。本研究中,在56kHz的超声频率下,采用不同超声强度(0、83、166、250、333mW/cm2),用以辅助浸浴法导入草鱼嗜水气单胞菌疫苗。结果显示,用166、250mW/cm2的超声波强度,免疫14d后,超声处理组溶菌酶活性和白细胞吞噬活性最高,显著高于对照组(P0.05);免疫28d后,血清凝集效价达到最高,显著高于对照组(P0.05)。超声波强度为166、250mW/cm2时,超声波处理组的相对免疫保护率高于对照组和其他处理组,分别达到66.5%和83.5%。本研究表明,用166mW/cm2和250mW/cm2的超声波强度处理后,鱼体免疫效价显著提高,表明该强度可作为适宜的超声波处理强度。实际生产中可采用166~250mW/cm2超声波强度处理,以辅助浸浴法有效导入草鱼细菌性疫苗,研究结果对于渔业生产应用和示范推广将提供重要指导。 相似文献
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美国马萨诸塞理工学院的科学家发明了一种利用超声波增强鱼类免疫功能的新技术。采用这种技术,能使鱼更容易接受疫苗、再生激素和抗菌素,从而可减少鱼病的发生。过去通常是将鱼放入加有抗菌素或其他药物的水中,以增强鱼的免疫功能, 相似文献
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鲢肌肉脂肪酸分离方法效果比较及组成特征分析 总被引：1，自引：0，他引：1
采用了三种不同方法,即超声波提取法、索氏提取法和氯仿-甲醇法,从鲢(Hypophthalmichys molitrix)肌肉中提取鱼油,继而进行酸性或碱性甲酯化,经气相色谱/质谱联用技术,对其脂肪酸组成特征进行了定性和定量分析。结果显示:鲢肌肉检测出25种脂肪酸,其中包括7种饱和脂肪酸,8种单不饱和脂肪酸和10种多不饱和脂肪酸。获得不饱和脂肪酸含量占总脂肪酸含量分别为41.39%、36.15%、33.55%,可见三种分离方法间存在明显分离效果差异。因此得出石油醚作溶剂的超声波萃取法是提取和分析鱼类脂肪酸较理想的方法。 相似文献
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C. D. SUSKI S. J. COOKE S. S. KILLEN† D. H. WAHL D. P. PHILIPP & B. L. TUFTS 《Fisheries Management and Ecology》2005,12(1):19-26
Abstract During live-release angling tournaments in North America, fish are typically retained in livewells onboard boats during the angling day. Mortality of fish occurs at some tournaments, and wave intensities and livewell conditions may influence mortality levels. This study used two species of fish targeted in live-release angling tournaments in North America (largemouth bass Micropterus salmoides L. and walleye Sander vitreus L.) to quantify the response(s) of fish in livewells to different wave treatments. Video analyses revealed that largemouth bass were active during low intensity disturbances, but during violent boat movements tended to settle to the bottom of the livewell and orient to face the direction of the disturbance. Walleye were less active than bass for all treatments, and additionally did not orient to face the direction of disturbance, consequently contacting the side of the livewell during boat rocking. These results are considered in the context of mortality at live-release tournaments. 相似文献
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In order to clarify the effectiveness of ultrasonication on vaccine delivery, juvenile sea bream, Pagrus major , were treated with eight different ultrasonic methods. A mixed vaccine against Vibrio alginolyticus and V. anguillarum was used to immunize the fish . The intensity and frequency of the ultrasound were 280 mW cm–2 and 35 kHz, respectively. The ultrasonic methods included continuous or pulsed ultrasound for 3 min, and continuous or pulsed ultrasound for 3 min before and/or after immersion for 3 min. Of all the eight ultrasonic methods tested, `pulsed ultrasound followed by immersion' and `immersion, pulsed ultrasound, and followed by immersion again' provided the best protection, which were comparable with protection of fish immunized by intraperitoneal injection. Moreover, the convenience of applying these two ultrasonic methods for immunization was comparable with the immersion method and was much better than intraperitoneal injection. If 2 × 108 CFU mL–1 of this mixed vaccine was used for vaccination repeatedly five times by ultrasonic methods, it could still produce good protection for the immunized sea bream. Therefore, the ultrasonic method is an effective and practical approach for fish vaccination on a large scale. 相似文献
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Numerical modeling of chaotic behavior for small-scale movements of demersal fishes in coastal water 总被引：1，自引：0，他引：1
ABSTRACT: The presented model involves the application of chaos theory to generate fish movements resulting from environmental stimuli. The model uses three steps within a model neural network such as input stimuli, central decision making and response output resulting in fish movements. The stimuli in the first step include the main abiotic and biotic factors, which could be quantified as an intensity parameter that was then normalized as a ratio between 0 and 1. The decision-making process can be generated using chaos dynamics with the stimuli parameters. The response of fish movements from the output signal representing movement speed and direction of fish can be re-regulated as main movement pattern depending on physiological state or life cycle by third response filtering. The simulation results seen as a movement pattern for sea bream and flounder using this neural chaotic model fitted very well to the observations of fish tracked in the sea by ultrasonic tracking methods. It was also revealed that the fish movement components generated as movement velocity and direction when in tidal flow had similar patterns to those patterns seen in field observations with similar irregular and chaotic variations with time. 相似文献
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福建省水产研究所设计的HDPE浮筏式消波堤,能在一定范围内有效削减海区波浪强度。为验证该型式消波堤的消波性能,笔者开展了罗源湾岗屿海域浮筏式消波堤内外的海浪现场调查及计算分析工作。结果表明：HDPE浮筏式防波堤具有一定的消波效果,消波效率达-33．33％～-42．86％。 相似文献
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GC—MS检测咸鱼中N-亚硝胺的条件优化 总被引：4，自引：0，他引：4
利用气相色谱-质谱联用（GC-MS）检测咸鱼中的N-亚硝胺,优化了样品前处理条件,比较了固相微萃取（SPME）和二氯甲烷超声萃取对N-亚硝胺的响应强度的影响,探讨了有机溶剂用量、萃取时间、萃取次数对测定的影响。采用选择离子法定性定量检测咸鱼中N-二甲基亚硝胺（NDMA）、N-二乙基亚硝胺（NDEA）、N-亚硝基吡咯烷（NPYR）和N-二丙基亚硝胺（NDPA）4种N-亚硝胺。结果显示,优化后的线性相关系数分别达到0.999 2、0.999 1、0.999 1和0.999 2;线性范围为0～10μg.mL-1;该方法重现性好,其相对标准偏差（RSD）均≤2.1%;空白加标回收率可达70%～80%;灵敏度高,检测限分别为0.038 6μg.kg-1、0.022 7μg.kg-1、0.031 6μg.kg-1和0.047 8μg.kg-1。 相似文献
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Active habitat selection by pre-settlement reef fishes 总被引：10，自引：0，他引：10
John Charles Montgomery Nicholas Tolimieri & Olivia Sophie Haine 《Fish and Fisheries》2001,2(3):261-277
Our understanding of habitat selection by reef fish larvae has changed dramatically in the last 10 years. Fish larvae have long been considered passive particles at the mercy of ocean currents, tides and weather events. For reef fishes, ecological evidence has shown that passive dispersal alone often cannot explain larval distributions, suggesting active behaviour by reef fish larvae. While behaviourally modified passive transport may be important, recent work demonstrates that some reef fish larvae have the capability to actively swim to settlement habitat. They can orientate to reefs from distances of at least 1 km and can swim at speeds of 13.5 cm s?1 for several days. The question then becomes, what are the cues that fish larvae use to orientate to reefs? Ambient reef sound has been shown to be attractive to reef fish larvae, and current research aims to understand better the nature and use of these acoustic cues. Other potential cues include chemoreception/olfaction, wave cues and visual location of reefs. A better understanding of active habitat selection and the underlying sensory and behavioural mechanisms will improve our knowledge of recruitment processes in reef fish ecology, and may have implications for active management of reef fish populations. 相似文献
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福建省的光诱鱿鱼敷网作业是福建省渔民在近十几年发展起来的一种用来专门捕捞枪乌贼的新型渔具.它具有投资少、生产费用低、劳动强度小、捕捞效率好、经济效益高等优点.目前其捕捞枪乌贼的产量已占所有作业捕捞枪乌贼产量的三分之二以上.然而,近年来,由于该作业的迅速发展,也带来了如诱集枪乌贼的灯光强度过大,渔获物中的幼鱼比例增多,渔场矛盾等问题.为了科学有效管理该作业,本文通过收集有关资料,整理分析,提出促进光诱鱿鱼敷网作业可持续发展的一些建议. 相似文献
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HDPE倾角入水式大型深水升降网箱的研究 总被引：2，自引：1，他引：1
为抵御强风暴袭击和躲避赤潮灾害对深水网箱结构和养殖鱼类的危害，研究设计了一种HDPE倾角入水式深水升降网箱，并在海上进行了自然放气与手动调控2种排气方式下网箱的沉浮试验，利用手动控制方式实现了网箱的成功升降。结果显示，试验网箱的平均沉降时间14min，平均上浮时间10min，其特点是沉浮操作比较简便、网箱配重小、换网快、隐患少、维护方便；并解析了试验中风、浪、流等海洋环境因素对网箱沉浮过程的作用与影响，解释了自然放气方式下网箱不能完全沉入水中的原因。 相似文献
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LI. Kangmin 《Fisheries Management and Ecology》1999,6(1):71-81
The economic development of the cities around Lake Taihu, China, has caused both environmental changes and ecological succession. The biodiversity of Lake Taihu has declined since 1970. Migratory fish, including anadromous, catadromous and semi-migratory fish, are either extinct or on the verge of extinction in Lake Taihu. Only lake dwellers persist. Several measures have been taken, such as restocking, closed seasons, sanctuaries for enhancement and even introductions to restore some original fish communities. Although these measures have achieved a certain degree of success, increased fishing activities or over-fishing have offset the benefits obtained. Moreover, cultural eutrophication of the lake and the pollution of the waterways connected with the lake are getting worse. This jeopardizes the remaining economically valuable species in the lake. Measures are required not only to control eutrophication and pollution, and to reduce the intensity of fishing, but also to address the wider biodiversity issues. 相似文献
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Abstract – An 11-year time series of hydroacoustic fish density estimates and fisheries statistics of vendace ( Coregonus albula (L.)) from four zones of a lake differing in trawling intensity was analyzed in order to test the hypothesis that intensive trawling has detrimental effects on pelagic fish stocks, especially vendace recruitment. The standardized fish density estimate in trawled zones showed no decrease in comparison to the non-trawled zone. No signs of recruitment failure associable with trawling intensity were found. The growth of vendace at the end of the study period was slower than that at the beginning, indicating a higher density, most clearly so in the zone with highest trawling intensity. No significant correlations were detected between 3-year mean trawling intensity and yield per unit effort of over-1-year-old vendace or fish density in any zone. Thus, no evidence to support the hypothesis was found. This was suggested to be due to density-dependent compensatory processes in recruitment and/or natural mortality effectively counteracting the population change induced by exploitation. Note 相似文献