海洋生物技术在水产养殖上的应用

海洋生物技术又称海洋生物工程,是以生命科学的知识来开发海洋的一门新兴学科,是直接或间接利用海洋生物或其成分,来完成某些商业目的的技术。近年来,海洋生物技术在水产养殖上的应用,已取得了一些成果,主要包括:基因转移技术,染色体操作,鱼类性别的控制,鱼病的早期诊断,预防和治疗,贝类的变态和附着,经济海藻的原生体质分离和海带单位体克隆的建立,现分述如下:     

光合细菌及其在水产养殖上的应用

<正> 有关光合细菌的研究,最早是1838年Ehrenberg发表关于红色细菌(purple bacteria)的论述。在此基础上,Moren,Cohe等于1887年建立Winogradsky体系,到1931年美国微生物学家Van Niel完成了近代光合细菌的基础研究。后来,人们在研究光合细菌基础理论的同时越来越注重其应用。尤其是日本小林正泰等人自1960年以来对此进行了广泛的研究,现在光合细菌在高浓度有机污水处理、农畜、水产等方面的应用,已取得显著成效。近年来,我国有少数研究者对光合细菌在水产养殖上的应用作了尝试,但目前尚处在室内研究和试验性生产应用阶段。笔者     

纤维素酶及其在水产养殖上的应用

本文从纤维素酶的来源、分类及作用机理出发,论述了纤维素酶在水产养殖上的应用情况及应用中应注意的一些问题,并对纤维素酶在未来的发展作一个展望.     

微胶囊技术在水产养殖上的应用

微胶囊技术是一项近50年才发展起来的新型技术。由于微胶囊物质有着许多独特的性能，已引起水产研究者极大的兴趣，已经得到广泛的应用。近十几年来，微胶囊技术在水产领域中的发展日益迅速，并体现出极高的应用价值和经济价值，展现出良好的发展前景，它对解决水产业中的技术难题、开拓新领域、改造传统产业具有十分重要的作用。     

原位杂交技术及其在水产养殖中的应用

原位杂交技术是近年来快速发展起来的一门新技术。本文介绍了原位杂交技术的基本原理和几种常用的原位杂交技术,并概述了原位杂交技术在水产养殖中的应用现状,包括该技术在基因定位、性别鉴定和病毒检测等领域的应用。此外,还对该技术的应用前景进行了展望。     

抗生素在水产养殖上的应用

1　抗生素的定义及发展历史抗生素是指由细菌、放线菌、真菌等微生物经培养而得到的某些产物或是用化学半合成法制造的相同或类似的物质 ,抗生素在低浓度下对特异性微生物 (包括细菌、立克农氏体、病毒、支原体、衣原体等 )有抑制生长或杀灭作用 ,抗生素原称为抗菌素 ,但由于它的作用超出单纯的抗菌范围 ,所以称为抗生素。抗生素的发展已有 5 0多年的历史 ,由于它具有卓越的疗效和广泛的用途 ,因而发展很快。1 943年以后 ,青霉素首先在美国形成大批量工业化生产 ,与此同时 ,一些饲养业者把抗生素的发酵残渣加在饲料中喂猪 ,并发现用这种饲料…     

生态养殖技术在水产养殖中的应用分析

近年来,我国水资源污染问题在不断加重,社会各界对水资源保护工作愈加重视。水产养殖是我国建设过程中必不可少的经济产业之一,在水产养殖的过程中,如果没有合理开发和利用水资源,会造成水域环境污染,不仅会对生态环境造成恶劣影响,还会降低水产品质量,所以应该采用生态养殖技术,在保障环境的前提下发展水产养殖业,本文就此进行了相关的阐述和分析。     

中国鱼类远缘杂交研究及其在水产养殖上的应用

在分析和归纳大量相关文献的基础上，对中国鱼类远缘杂交研究的概况及其有关问题进行全面的介绍和评述：（1）鱼类远缘杂交的等级，包括目间、科间、亚科间、属间和种间杂交；（2）鱼类远缘杂交的相容性，涉及鱼类远缘杂交的可交配性、鱼类远缘杂种的可育性以及鱼类远缘杂交不相容的原因分析等；（3）鱼类远缘杂交在水产养殖上的各方面应用，如杂种优势利用，鱼类性别控制以及诱导多倍体、雌核发育和雄核发育等。本文旨在为对今后进一步开展鱼类远缘杂交研究提供理论参考。     

浅谈生态养殖技术在水产养殖中的应用

当前生态发展理念的日益盛行,为水产养殖业的发展拓宽了空间。在水产养殖的过程中通过应用生态养殖技术,加大生态养殖技术的推广力度,从而推动水产养殖的生态化发展。本文通过阐述水产生态养殖技术要点,并根据实际情况提出生态养殖技术在水产养殖中的应用策略,旨在增强水产养殖的经济效益。     

Water disinfection by ozonation has advantages over UV irradiation in a brackish water recirculation aquaculture system for Pacific white shrimp (Litopenaeus vannamei)

By keeping tropical shrimp, like Litopenaeus vannamei, in recirculating aquaculture systems (RAS), valuable food for human consumption can be produced sustainable. L. vannamei tolerates low salinities, and therefore, the systems can operate under brackish water conditions. The stabilization of the microbial community in RAS might be difficult under high organic loads, and therefore, water treatment measures like UV irradiation or ozone application are commonly used for bacterial reduction. To investigate the impact of these measures, the effects of UV irradiation and ozone application were studied in small-scale brackish water RAS with a salinity of 15‰ stocked with L. vannamei. UV reactors with 7 and 9 W were used, and by ozonizers with a power of 5–50 mg/hr, the redox potential in the water was adjusted to 350 mV. Ozone had a stabilizing effect on the microbial composition in the water and on biofilms of tank surfaces and shrimp carapaces, prevented an increase of nitrite and accelerated the degradation of nitrate in the water. UV irradiation led to changes in the microbial composition and was less effective in optimizing the chemical water quality. Thus, the use of ozone could be recommended for water treatment in brackish water RAS for shrimp.     

酵母细胞壁及其在水产健康养殖中的应用

酵母细胞壁是一种环保型绿色饲料添加剂,在水产健康养殖中应用十分广泛。文章论述了酵母细胞壁的主要组成成分、作用机理、功能特点及其在水产健康养殖中的应用情况,并对其应用前景作了分析。     

荧光实时定量PCR技术及其在水产养殖研究中的应用

荧光实时定量PCR技术是近年来快速发展起来的一门新技术,它是核酸探针技术、荧光共振能量传递技术(Fluorescence Resonance Energy Transfer,FRET)和PCR技术的有机结合。与常规PCR相比,它具有特异性更强、有效解决PCR污染问题、自动化程度高、能较准确定量等特点。本文综述了荧光实时定量PCR技术的基本原理及几种广泛应用的荧光化学方法,并概述了荧光实时定量PCR技术在水产养殖研究领域的应用现状,并对荧光实时定量PCR技术的应用前景进行了展望。     

微生态制剂及其在水产养殖中的应用研究现状

论述了微生态制剂的种类、作用机理及其作为水质改良及饲料添加剂在水产养殖领域的应用现状。对微生态制剂在使用中的影响因子、存在问题以及发展趋势进行了初步分析。     

Isolation of the non-fastidious microalga with astaxanthin-accumulating property and its potential for application to aquaculture

Astaxanthin has recently attracted considerable attention for its biological properties such as the antioxidant activity as well as a coloring agent used for farmed fish. However, its biological production, mainly by a green microalgae Haematococcus pluvialis, is costly because of its fastidious growth characters. Therefore, for future applications of biological astaxanthin production in aquaculture, non-fastidious microalgal strains were isolated from environmental samples, examined for their astaxanthin-accumulating activity, and characterized phylogenetically. While β-carotene was found in all tested isolates, one isolate, GK12, from activated sludge of a sewage treatment plant accumulated 2.5 ± 0.36 mg/g dry cell of free astaxanthin de novo under photoautotrophic culture condition, which was comparable to photoautotrophic cultures of other known astaxanthin-accumulating microorganisms. Mixotrophic culture conditions increased GK12 biomass, but astaxanthin content was decreased, suggesting that the simple photoautotrophic cultivation is more efficient way for GK12 to produce astaxanthin than mixotrophic cultivation. A phylogenetic study of SSU rDNA strongly suggested that GK12 is a novel species in the genus Monoraphidium, Chlorophyta. Besides making efforts to increase astaxanthin-productivity of known astaxanthin accumulators, it is also beneficial to study GK12 from the view point of applications to aquaculture.     

病原检测基因芯片应用及在水产病害检测的前景

基因芯片技术是近年来迅速发展起来的一项新技术,已成为国内外研究的热点。作为生物芯片技术发展中最完备的一个分支,基因芯片以其高通量、高灵敏性、高特异性的特点,在细菌、病毒、真菌等病原检测和鉴定方面发挥着越来越重要的作用。本文介绍了基因芯片的原理和作为检测手段的优越性,并综述了基因芯片技术在细菌和病毒检测方面的应用,分析了现有水产动物病原检测技术,提出了在现有水产动物病原生物信息学的基础上,研发水产养殖动物病害诊断基因芯片的策略。     

Foam fractionation and ozonation in freshwater recirculation aquaculture systems

Foam fractionation is often considered an ineffective way of removing organic matter from freshwater due to the low surface tension of the water. There is, however, a lack of studies testing foam fractionation efficiency in replicated freshwater recirculating aquaculture systems (RAS). Foam fractionation can be applied with or without ozone. Ozone is a strong oxidiser previously shown to improve water quality and protein skimmer efficiency. To test the efficiency of foam fractionation and ozonation (20 g O₃ kg^-1 feed) separately and in combination in freshwater RAS, a two-by-two factorial trial was conducted with each main factor at two levels (applied or not applied). Each treatment combination was carried out in triplicates using 12 replicated pilot scale RAS stocked with juvenile rainbow trout (Oncorhynchus mykiss) and operated at a feed loading of 1.66 kg feed m^-3 make-up water. The trial lasted 8 weeks and samples were obtained once a week. Ozone applied by itself significantly reduced the number of particles (83%), bacterial activity (48%) and particulate BOD₅ (5-days biochemical oxygen demand; 54%), and increased ultra violet transmittance (UVT; 43%) compared to the untreated control group. Foam fractionation by itself lead to significant reductions in particle numbers and volume (58% and 62%, respectively), turbidity (62%), bacterial activity (54%) and total BOD₅ (51%). A combination of both treatments resulted in a significant additional improvement of important water quality variables, including a 75% reduction in total BOD₅, 79% reduction in turbidity, 89% reduction in particle numbers and 90% reduction in bacterial activity compared to the control. The removal efficiencies were within the same range as those observed in previous studies conducted with foam fractionators in saltwater systems (with or without ozone), corroborating that foam fractionation may become a useful tool for controlling organic matter build-up and bacterial loads in freshwater RAS.     

Water quality upstream and downstream of a commercial oyster aquaculture facility in Chesapeake Bay,USA

Oyster aquaculture is an expanding industry in the Chesapeake Bay. Oysters remove nitrogen (N) and phosphorus (P) from the water column through filtration and conversion of phytoplankton into shell and tissue, but also continuously excrete these same nutrients back into the water column as inorganic compounds readily available for plant or algal uptake. The objective of this study was to assess multiple water quality parameters upstream and downstream of a commercial oyster aquaculture facility in the mesohaline region of the Chesapeake Bay. Results of the study indicated a 78.4% average increase in total ammonia nitrogen (TAN) concentration and a 19.4% decrease in chlorophyll-a (Chl-a) concentration downstream of the facility. There was no significant change in the concentration of reactive phosphate (RP), nitrate–nitrogen (NO₃⁻–N), or nitrite–nitrogen (NO₂⁻–N) as water passed through the facility. It was determined that velocity of water through the facility had no influence on the change in TAN or Chl-a concentration from upstream to downstream of the facility. Increased reduction in Chl-a concentration from upstream to downstream was related to higher upstream concentrations of Chl-a. There was no correlation between increased rates of Chl-a removal and downstream TAN. Results of this study suggest that oyster aquaculture can significantly increase the amount of available inorganic nitrogen in the water column immediately downstream of a facility, independent of upstream availability of phytoplankton and flow velocity of water through the facility.     

Design and operation of a low-cost and compact autonomous buoy system for use in coastal aquaculture and water quality monitoring

The need to ensure future food security and issues of varying estuarine water quality is driving the expansion of aquaculture into near-shore coastal waters. It is prudent to fully evaluate new or proposed aquaculture sites, prior to any substantial financial investment in infrastructure and staffing. Measurements of water temperature, salinity and dissolved oxygen can be used to gain insight into the physical, chemical and biological water quality conditions within a farm site, towards identifying its suitability for farming, both for the stock species of interest and for assessing the potential risk from harmful or toxic algae. The latter can cause closure of shellfish harvesting. Unfortunately, commercial scientific monitoring systems can be cost prohibitive for small organisations and companies to purchase and operate. Here we describe the design, construction and deployment of a low cost (<£ 5000) monitoring buoy suitable for use within a near-shore aquaculture farm or bathing waters. The mooring includes a suite of sensors designed for supporting and understanding variations in near-shore physical, chemical and biological water quality. The system has been designed so that it can be operated and maintained by non-scientific staff, whilst still providing good quality scientific data. Data collected from two deployments totalling 14 months, one in a coastal bay location, another in an estuary, have illustrated the robust design and provided insight into the suitability of these sites for aquaculture and the potential occurrence of a toxin causing algae (Dinophysis spp.). The instruments maintained good accuracy during the deployments when compared to independent in situ measurements (e.g. RMSE 0.13–0.16 °C, bias 0.03–0.08 °C) enabling stratification and biological features to be identified, along with confirming that the waters were suitable for mussel (Mytilus spp.) and lobster (Homarus gammarus) aquaculture, whilst sites showed conditions agreeable for Dinophysis spp.