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1.
鱼类消化酶活性的影响因素 总被引：4，自引：0，他引：4
鱼类消化酶活性受多种因素的影响,着重讨论了鱼类食性、不同生长发育阶段、饵料和环境温度因素对其蛋白酶、淀粉酶和脂肪酶活性的影响;深入了解影响鱼类消化酶活性的因素,对人工饵料的优化和水产养殖业的健康发展都有重要的指导意义。 相似文献
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水产养殖的实质是一种以"物"换"物"的过程,也就是通过水产养殖,把饵料或肥料转化为水产品的过程.水产养殖单位面积产量的高低和经济效益的好坏,在很大程度上取决于使用的饵料是否合理和投饵的技术是否科学.对于水产养殖来说,正确合理地选用饵料,科学合理地投喂,是促进养殖动物快速生长,提高饵料转化率,降低饵料成本,提高经济效益的关键.饵料投喂是水产养殖中的一大关键环节,只有正确把握饲养鱼类的投饵数量,科学投喂,才能提高饵料的利用率,保证养鱼增产增收增效.目前对于鱼类的研究多集中于鱼类养殖技术、营养和饵料开发方面,对于科学的饵料投喂的报道较为少见.而这方面的研究结果对于我们开展水产养殖业、提高效益、节省成本以及在环境保护方面是很重要的.因此,科学把握水产养殖中饵料投喂显得尤为重要.投饵技术包括投饵量的确定、投饵时间、投饵次数、投饵方法和投饵原则.下面就投饵技术几个方面以及饵料投喂存在的问题进行阐述,期望能使读者对科学投饵有一个清晰的认识,并且对于解决饵料投喂存在的问题提供借鉴. 相似文献
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<正>随着水产养殖业朝着集约化、规范化、系统化的方向迈进,传统的养殖模式和方法——需要会看水体的颜色及实时变化,需要在鱼类的不同生长阶段投喂不同的饵料,需要每天都做到定时、定点、定质、定量地投喂饵料,需要在鱼类的整个生长周期都加强日常管理和每日的巡塘、跑塘工作,定期人工换水,定期检测化验水样,已经越来越不适应高密度精养甚至是设施渔业对水产养殖业提出的新的、更严苛的要求。与此同时,中国的劳动力成本也在逐年提高,经济社会的快速发展也要求人们能够拿出更多的时间去 相似文献
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由于鱼肉的营养价值较高,口感很好,能够满足人们日常生活所需要的营养补充,因而人们对于各种鱼类的需求量很大,这在一定程度上刺激了水产养殖规模的扩大,促进我国水产养殖业的发展。为此,水产养殖业只有不断提升鱼类质量,保证鱼类的品质才能满足人们的日常生活需求。基于此,水产养殖行业不仅要重视鱼类的品种,还要高度重视鱼类的健康问题,以更高的品质带动水产养殖业的持续健康发展。 相似文献
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水产动物苗种是水产养殖业的物质基础。随着海水鱼类养殖规模的迅速扩大,对其苗种的需求量急剧增加,海区鱼苗的自然资源已不能满足生产的需要。我国海水鱼类人工繁殖研究是从20世纪50年代末开始的,经过40多年的开发和研究,到目前为止,约有40多种海水鱼类获得人工繁殖成功,并达到批量生产水平。在所有这些鱼苗的人工培育中,对鱼苗饵料投喂技术的掌控,是一个关系到鱼苗生产成败的技术关键。因此,本文就工厂化育苗过程中,饵料投喂技术谈几点体会,供广大苗种生产者参考。一、饵料种类目前,在海水鱼种苗生产中所采用的饵料分生物饵料和非生物饵料… 相似文献
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饥饿对鱼类生理生化的影响 总被引：6，自引：0，他引：6
饥饿对鱼类有多方面的影响。着重讨论了饥饿状态下鱼类能量的利用以及饥饿状态下消化器官组织结构、消化酶活力、血液组分的变化。深入研究饥饿状态下鱼类生理生化变化,一方面有助于了解鱼类适应饥饿胁迫的生态对策,另一方面对渔业资源管理以及水产养殖生产等也有重要的指导意义。 相似文献
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目前，我国海洋总体质量不容乐观，特别是近岸海域和生态恶化状况仍未得到有效控制。近海和内陆水域主要经济鱼类的产卵场和索饵育肥场，由于污染使生态遭受破坏造成饵料生物减少、水生生物的亲体繁殖力和幼体存活力急剧下降，致使大量水生生物得不到有效补充，水产养殖业也存在着病害和苗种质量下降等突出问题。由于养殖业环境的变化，渔饲料等造成的水域污染也影响我国的水产品质量安全。 相似文献
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本实验以初始体质量为(4.88±0.90)g、体长为(4.85±0.32)cm的红小丑鱼(Amphiprion frenatus)为养殖对象,研究饲料中添加0(对照组)、2‰、4‰、6‰、8‰的虾青素对红小丑鱼消化酶活性的影响。本试验每组3个重复,每个重复6尾鱼,饱食投喂2次/d(投喂时间为08∶30和14∶30),试验周期为20 d。结果表明:添加虾青素组的红小丑鱼胃肠消化酶活性均高于未添加虾青素组,当虾青素添加量为4‰时,红小丑鱼前肠蛋白酶、脂肪酶、淀粉酶以及后肠淀粉酶活性达到最高(P0.05);当添加量为6‰时,其胃脂肪酶和淀粉酶活性最高(P0.05);当添加量为8‰时,其胃和后肠的蛋白酶以及后肠脂肪酶的活性达到最高(P0.05)。因此,在饲料中添加4‰~8‰的虾青素能够较有效地提高红小丑鱼消化器官的消化酶活性。 相似文献
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Modulation of nutrient digestibility and digestive enzyme activities in aquatic animals: The functional feed additives scenario 
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下载免费PDF全文 Considering the costs of feed costs (nearly 60% of production cost), nutrition, feeding and feed utilization are among the most important factors in commercial aquaculture. During the last decade, administration of functional feed additives has been practiced for enhancing nutrient digestibility and digestive enzyme activities of cultured fish and shellfish. Traditionally, antibiotics were used for boosting growth performance and nutrient digestibility in commercial aquaculture. However, emergence of resistance pathogens and possible risk to human health resulted in limitation or prohibition of prophylactic administration of antibiotics. Recently, there was increasing attentions towards dietary administration of functional feed additives that include probiotics, prebiotics and synbiotics for elevation of digestive enzyme activity and nutrient digestibility. The results of those studies revealed contradictory effects of different pro‐, pre‐ or synbiotics on various fish species. It seems that the effects are species specific and related to modulation of the intestinal microbiota. In view of this issue, the present review provides a comprehensive sight on the effects of different pro‐, pre‐ and synbiotics on digestive enzyme activity and nutrient digestibility in different species with special focus on the mode of action. In addition, the present review highlighted the gaps of existing knowledge as well as suggesting the subjects which needs additional studies. 相似文献
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R. Martínez-Lagos D. Tovar-Ramírez V. Gracia-López J. P. Lazo 《Fish physiology and biochemistry》2014,40(3):773-785
The leopard grouper is an endemic species of the Mexican Pacific with an important commercial fishery and good aquaculture potential. In order to assess the digestive capacity of this species during the larval period and aid in the formulation of adequate weaning diets, this study aimed to characterize the ontogeny of digestive enzymes during development of the digestive system. Digestive enzymes trypsin, chymotrypsin, acid protease, leucine–alanine peptidase, alkaline phosphatase, aminopeptidase N, lipase, amylase and maltase were quantified in larvae fed live prey and weaned onto a formulated microdiet at 31 days after hatching (DAH) and compared with fasting larvae. Enzyme activity for trypsin, lipase and amylase were detected before the opening of the mouth and the onset of exogenous feeding, indicating a precocious development of the digestive system that has been described in many fish species. The intracellular enzyme activity of leucine–alanine peptidase was high during the first days of development, with a tendency to decrease as larvae developed, reaching undetectable levels at the end of the experimental period. In contrast, activities of enzymes located in the intestinal brush border (i.e., aminopeptidase and alkaline phosphatase) were low at the start of exogenous feeding but progressively increased with larval development, indicating the gradual maturation of the digestive system. Based on our results, we conclude that leopard grouper larvae possess a functional digestive system at hatching and before the onset of exogenous feeding. The significant increase in the activity of trypsin, lipase, amylase and acid protease between 30 and 40 DAH suggests that larvae of this species can be successfully weaned onto microdiets during this period. 相似文献
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生物絮团技术对异育银鲫生长性能和抗性的影响 总被引：2，自引：1，他引：1
为研究生物絮团技术(Biofloc Technology,BFT)在沿海滩涂鱼类养殖中的应用效果,本实验以滩涂主要养殖种类——异育银鲫(Carassius auratus gibelio)为研究对象,按照BFT养殖模式(BFT组,不换水,只补存蒸发掉或取样部分的水分)和一般养殖模式(对照组,每日换水1次,每次换水1/4~1/3)分别饲养,测定各处理组异育银鲫的生长指标、消化酶活性和免疫相关酶活性,应用实时荧光定量PCR法定量分析热休克蛋白HSP70的相对表达,人工感染试验对比分析BFT养殖模式组和一般养殖模式组异育银鲫生长性能和抗性的变化。结果显示:(1)BFT组异育银鲫增重率、特定生长率和存活率均高于对照组(P0.01),肥满度、脏体比和肝体比与对照组间无显著差异(P0.05);(2)BFT组异育银鲫肠道中淀粉酶、脂肪酶和胃蛋白酶活性显著高于对照组(P0.05),分别提高了53.10%、28.10%和17.99%;(3)BFT组异育银鲫体表黏液中超氧化物歧化酶活性、血清中总抗氧化能力和溶菌酶活性高于对照组(P0.01);(4)BFT组脾、肾、肝和鳃中热休克蛋白HSP70的表达量分别上调了1.29倍、1.34倍、1.87倍和1.68倍;(5)嗜水气单胞菌(Aeromonas hydrophilia)人工感染试验证实,BFT组异育银鲫抗细菌感染能力显著增强。研究表明,BFT养殖模式适于异育银鲫养殖,可促进鱼体生长,增强其应激能力和抗病力。 相似文献
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中国水产养殖种类组成、不投饵率和营养级 总被引：6，自引：1，他引：5
根据1950–2014年水产养殖种(类)有关统计和调研数据,并在对养殖投饵率、饲料中鱼粉鱼油比例、各类饵料(配合饲料、鲜杂鱼/低值贝类/活鱼、天然饵料等)营养级等基本参数进行估算的基础上,研究分析了中国水产养殖种类组成、生物多样性、不投饵率和营养级的特点及其变化。结果表明:中国水产养殖结构相对稳定,变化较小,其显著特点是种类多样性丰富、优势种显著、营养层次多、营养级低、生态效率高、生物量产出多。其中:(1)养殖种类296个、品种143个,合计为439个。种类组成区域差异明显,淡水养殖鱼类占绝对优势,如2014年草鱼、鲢鱼、鳙鱼、鲤鱼、鲫鱼和罗非鱼排名前6个种类的养殖占淡水养殖产量69.6%,其次为甲壳类、其他类、贝类及藻类,而海水养殖则以贝藻类为主,如2014年牡蛎、蛤、扇贝、海带、贻贝和蛏6个种(类)的养殖占海水养殖产量71.3%,其次为甲壳类、鱼类及其他类;(2)养殖种类多样性特征显著,与世界其他主要水产养殖国家相比,独为一支,具较高的多样性、丰富度和均匀度,发展态势良好;(3)由于养殖方式从天然养殖向投饵养殖转变,不投饵率呈明显下降趋势,从1995年90.5%降至2014年53.8%(淡水35.7%,海水83.0%),但与世界平均水平相比,仍保持较高的水准;(4)与世界相比,营养级低且较稳定。由于配合饲料的广泛使用及其鱼粉鱼油使用量减少,近年营养级略有下降,从2005年较高的2.32降至2014年2.25(淡水2.35,海水2.10)。营养级金字塔由4级构成,以营养级2为主,近年占70%,表明其生态系统有较多的生物量产出。中国水产养殖未来发展需要遵循绿色、可持续和环境友好的发展理念,探讨适宜的、特点各异的新生产模式,发展以养殖容量为基础的生态系统水平的水产养殖管理,建设环境友好型的水产养殖业,为保障国家食物安全、促进生态文明建设作出更大贡献。 相似文献
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Alvarez-González CA Moyano-López FJ Civera-Cerecedo R Carrasco-Chávez V Ortiz-Galindo JL Dumas S 《Fish physiology and biochemistry》2008,34(4):373-384
Spotted sand bass Paralabrax maculatofasciatus is a potential aquaculture species in Northwest Mexico. In the last few years it has been possible to close its life cycle
and to develop larviculture technology at on pilot scale using live food, however survival values are low (11%) and improvements
in growth and survival requires the study of the morpho-physiological development during the initial ontogeny. In this research
digestive activity of several enzymes were evaluated in larvae, from hatching to 30 days after hatching (dah), and in live
prey (rotifers and Artemia), by use of biochemical and electrophoretic techniques. This paper, is the first of two parts, and covers only the biochemical
analysis. All digestive enzyme activities were detected from mouth opening; however the, maximum activities varied among different
digestive enzymes. For alkaline protease and trypsin the maximum activities were detected from 12 to 18 dah. Acid protease
activity was observed from day 12 onwards. The other digestive enzymes appear between days 4 and 18 after hatching, with marked
fluctuations. These activities indicate the beginning of the juvenile stage and the maturation of the digestive system, in
agreement with changes that occur during morpho-physiological development and food changes from rotifers to Artemia. All enzymatic activities were detected in rotifers and Artemia, and their contribution to enhancement the digestion capacity of the larvae appears to be low, but cannot be minimised. We
concluded that the enzymatic equipment of P. maculatofasciatus larvae is similar to that of other marine fish species, that it becomes complete between days 12 and 18 after hatching, and
that it is totally efficient up to 25 dah. 相似文献
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随着人口与经济的发展,水产养殖业在世界范围内迅速兴起,集约型工厂化循环水养殖因其高密度、低污染、高效率等独特的优势,契合水产养殖业绿色发展理念,已成为水产养殖转型升级的重要方向之一。水作为循环水养殖系统中重要的环境因子,其流态能够直接影响鱼类的生长及福利,同样,鱼类存在及运动也会影响到系统流态的构建。本文综合分析了循环水养殖系统中流场条件对不同鱼类生长发育及福利的影响,鱼类及其运动行为对养殖池内水动力条件及性能的影响,以及鱼类对养殖池内流场流态、水体混合等的影响。将研究鱼类运动对流场特性的影响方法主要归纳为实测法和数值研究,通过对比分析2种方法的优点和不足之处,并结合当前循环水养殖产业系统构建中的问题提出针对性方法建议,旨在为系统中水动力条件的设计拓展思路,促进循环水养殖产业流态构建向“鱼”与“水”兼顾的方向发展。 相似文献
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The Ghana ministry of fisheries and the ministry of Agriculture provide free extension services and other technical services to fish farmers in Ghana, e.g. producing fingerlings at government-operated fish hatcheries for sale to farmers. Non-governmental organizations and universities have also provided some technical assistance to fish farmers in efforts towards the development of aquaculture in Ghana. The study identified the various sources of aquaculture information to Ghanaian fish farmers and examined the factors that affected their decision to utilize these alternative sources of information. Using choice modelling techniques, the study found that the probability of farmers seeking information on aquaculture from the Ghana government increases with literacy by about 43% more than with illiteracy and by about 34% with an increase in total size of ponds. The probability that a literate farmer will choose to obtain aquaculture information from a non-governmental organization decreased by about 10% compared with an illiterate farmer. The probability of choosing 'other sources' for aquaculture information increased by about 27% for farmers residing in Ashanti region compared with farmers in the Brong-Ahafo region but the probability of farmers seeking information from 'other sources' decreased with literacy and number of years farming. 相似文献
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Analysis of bacterial community and bacterial nutritional enzyme activity associated with the digestive tract of wild Chilean octopus (Octopus mimus Gould, 1852) 下载免费PDF全文
下载免费PDF全文 Information on the bacterial community associated with octopus is very scarce, unlike fish and other molluscs. This study revealed the bacterial community associated with digestive tract of wild Chilean octopus Octopus mimus using a culture‐dependent method and 16S rDNA clone library. Moreover, we analysed the bacterial nutritional enzyme activity of culturable bacteria. A culture‐dependent method showed that the composition of the culturable bacterial community was substantially different between female and male octopus. The predominant species in female octopus were Vibrionaceae and Streptococcaceae, whereas only Vibrionaceae was dominated in male octopus. Bacterial nutritional enzyme activities of culturable bacteria from male octopus were much higher than female octopus. The 16S rDNA clone library analysis showed that the bacterial community of male octopus exhibited a higher diversity than that of female octopus. The genus Mycoplasma was the predominant bacteria in the digestive tract of all octopus samples. The results obtained in this study raise the possibility that each octopus has different food consumption due to different bacterial community and nutritional enzyme activity, although Mycoplasma sp. is one of the predominant bacteria in the digestive tract. Moreover, our results are useful for the future of microbiological investigation associated with the octopus and for probiotics in the octopus aquaculture. 相似文献