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文章综述了鱼类游泳能力的研究概况、鱼类游泳速度的分类和鱼类游泳能力的测定方法,分析比较了各种方法的优劣,以期为进一步优化鱼类游泳能力的评价指标、完善测试鱼类游泳能力的方法与手段提供参考。  相似文献
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晁帅  王萍  娄宇栋  竺琰  桂福坤 《水产学报》2017,41(3):392-400
本文以深水网箱养殖美国红鱼为研究对象,通过研究其游泳时的主要能量物质和代谢产物的变化规律,构建美国红鱼的游泳体能分配模型,最后结合特定的潮流规律,建立养殖海区最大潮流选择的理论方法。研究结果表明,美国红鱼游泳过程中,血糖浓度会显著提高,肌糖原有少量减少,肝糖原会显著降低,鱼类游泳接近疲劳时,肝糖原浓度亦接近耗尽;美国红鱼以较高速度游泳过程中,血乳酸和肌乳酸浓度会有较明显的增加,表明美国红鱼游泳过程伴随着无氧呼吸和有氧呼吸两种能量物质代谢过程。本文提出以肝糖原浓度作为判定鱼类持续游泳能力的重要指标,并建立了基于肝糖原储能消耗的美国红鱼游泳体能分配模型。最后基于美国红鱼体能分配模型,结合养殖海区潮流规律,提出了美国红鱼养殖海区最大潮流流速选择的计算方法。本文提出的鱼类游泳体能分配模型构建方法以及鱼类养殖海区潮流选择论证方法,可为相关研究提供新的途径,为深水网箱、浅海围网等海洋养殖模式的海区潮流选址提供科学的参考依据。  相似文献
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在鱼类游泳能力测定装置中,采用流速递增法,测定了(10、15、20、25℃)条件下鲢幼鱼两次疲劳运动过程中临界游泳速度和耗氧率的变化,研究重复疲劳运动对鲢幼鱼游泳能力和活动代谢率的影响。结果表明,在10℃-25℃温度范围内,鲢幼鱼临界游泳速度随温度升高而呈线性增加(Ucrit,1=3.52 0.14T,R2=0.98,P<0.05;Ucrit,2=3.33 0.09T,R2=0.97,P<0.05)。运动最大耗氧量(MMR)和标准代谢率(SMR)均随温度升高而增加,且第一次测试耗氧率显著高于第二次测试耗氧率。运动后过量耗氧率(EPOC)随着温度升高而增加,与温度相关性显著(P=0.024);第二次测试疲劳后恢复耗氧率较第一次低,疲劳运动对EPOC影响不显著(P=0.36),结果表明适宜温度范围内温度对游泳能力和活动代谢起促进作用,疲劳运动对游泳能力和活动代谢不利,有一定抑制作用。以鲢幼鱼为研究对象,研究了温度和疲劳运动胁迫下代谢行为,为制定有效的鱼道提供数据参考。  相似文献
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Fish differentially provision resources to eggs and larvae to optimise survival during the critical early life‐history period. Resource allocation is limited by a trade‐off between egg size and fecundity, and the optimal strategy varies with habitat type. This study examines the consequences of egg size differences for the early life‐histories of four closely related galaxiid species which occur in contrasting habitat types on the South Island, New Zealand. Headwater species had substantially larger water‐hardened eggs, longer incubation times, and newly hatched larvae were on average up to 41% longer than lower catchment species. Significant interspecific differences in gape diameter, eye diameter and myomere depth were also observed. Swimming ability was positively associated with larval length at hatch. Interspecific differences in length and swimming ability were generally maintained throughout the larval period, despite larvae being reared under relatively benign conditions where many other studies suggest initial differences should disappear. These results demonstrate the consequences of differential maternal provisioning to the egg for larval traits. The larger larvae of headwater species are likely to be more resistant to starvation and have improved foraging ability compared to lower catchment species; traits which are likely to confer them survival advantages in the low productivity, food‐scarce environments they occupy. The smaller larvae of lower catchment species are likely to be a consequence of females investing in fecundity in these relatively resource‐rich streams.  相似文献
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Abstract – Understanding the larval ecology of individual fish species is fundamental in ensuring their long‐term conservation. The endangered eastern freshwater cod, Maccullochella ikei, is endemic to the Clarence and Richmond River systems of north‐eastern New South Wales, Australia. Little is known about the behaviour of larval M. ikei in the wild, particularly before and after the swim‐up stage, and following dispersal from the nest site. The aims of this study were to quantify the swimming ability, depth selection, light preference and substrate selection of hatchling to day‐30 M. ikei under controlled laboratory conditions, and to describe its growth and development over the same period. Maccullochella ikei larvae grew constantly but not consistently during the experiment. Exogenous feeding commenced around day 12, prior to the full exhaustion of the yolk. Maximal swimming ability improved daily, but maximum swimming speed declined significantly between days 12 and 13 and remained low. Maccullochella ikei larvae were initially photonegative but were positively phototactic by day 10. Depth selection was for the benthos until day 8, beyond which time larvae dispersed to all depths when released. Substrate selection was for sand in younger larvae but changed to upstream substrates as the experiment progressed. The results of the current study suggest that the period between day 10 and day 20 is critical in the early ontogeny of M. ikei, when it switched phototrophic behaviour, transitioned from endogenous to exogenous feeding and experienced a decline in swimming ability.  相似文献
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Abstract –  The downstream migration of juvenile salmonids has previously been considered predominantly passive. It has been argued that passive displacement during periods of darkness is, partially at least, a result of an inability to maintain a fixed position in the absence of visual cues. In this study, behaviour of juvenile Pacific salmonids was assessed under conditions of light and dark as they passed through an artificial channel and encountered a submerged weir. Results indicated that when light, fish formed schools and actively explored the channel. Conversely, when dark (infrared illumination only) they did not form schools, but maintained randomly distributed positions holding station against the flow. As a consequence, more fish approached and either passed, or rejected, the weir when light. The majority of fish that passed the weir did so within the first minute of each trial. Fish predominantly passed through the channel facing downstream and changed orientation prior to passing tail first over the weir crest in the presence and absence of visual cues. The orientation switch was less common when dark. This study shows, at a fine-resolution scale, that downstream movement of juvenile salmonids can be inhibited as fish exhibit alternative behaviours in the absence of visual cues. Downstream movement was not predominantly passive. Fish passage design should not be based on the assumption that downstream migration is passive.  相似文献
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