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Journal of Environmental Sciences 2002年第4期14卷 508-517页

作者： Mfon T.UDO Department of fisheries and aquaculture Faculty of AgricultureUniversity of Uyo

Aspects of the trophic attributes of the mudskipper, Periophthalmus barbarus occurring in the mangrove swamps of Imo River Estuary, Nigeria, were investigated during a 12 month period (April, 1992\_March, 1993). Feeding intensity increased with size, it was higher in the dry season(November\_April) than in the wet season(May\_October), monthly changes in the indices of feeding intensity were significantly correlated. Major food objects comprised detritus and benthic algae; crustaceans, insects, macrophyte matter and sand grains were minor food objects while fish, molluscs, Chilopoda, nematodes and fungi were unconsciously devoured objects. Diet varied seasonally; algae and sesarmid crabs were generally more in the dry season than during the rains whereas FPOM and fish increased in the wet over dry season. The mudskipper display a high degree of euryphagy and can be considered as a generalist and an omnivore. The lower trophic status of P. barbarus qualifies it as a good aquaculture candidate. Food richness was higher in big sized class(BSC) than small sized class(SSC). Size based and seasonal variations were not apparent in food richness. Diet breadth was higher in the BSC than the SSC, there was dry season increase in diet breadth.

关键词： Periophthalmus barbarus indices of feeding intensity diet composition mangrove swamp Imo River Estuary Nigeria

Experimental Study of An aquaculture Net Cage in Waves and Current

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China Ocean Engineering 2015年第3期29卷 325-340页

作者： David KRISTIANSEN Pal LADER Фsten JENSEN David FREDRIKSSON SINTEF fisheries and aquaculture united States Naval Academy

Model experiments of a floating fish cage subjected to waves and current have been performed. The objective was to study the dynamic behaviour of the fish cage model in waves and current. The fish cage model was composed of a model net, a flexible floating collar of the circular plastic type and a weight system. It was found that there are many wave periods in which cancellation of the wave-induced forces on the model occur. These cancellation wave periods are within the range of dimensioning wave periods commonly used for testing of fish farm structures and hence are important to be aware of. Large deformations of the net under realistic wave and current conditions were observed, where contact between the net and other parts of the structure were identified. This may cause damages to the net due to abrasion.

关键词： aquaculture structure hydrodynamic loads hydroelasticity

A corpus-based approach to understanding market access in fisheries and aquaculture international business research:A systematic literature review

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aquaculture and fisheries 2019年第6期4卷 219-230页

作者： Cheryl Marie Cordeiro Nofima The Norwegian Institute of FoodFisheries and Aquaculture ResearchMuninbakken 9BreivikaTromsø9291Norway

Although fisheries and aquaculture studies might seem marginal to international business(IB)studies in general,fisheries and aquaculture IB(FAIB)management is currently facing increasing pressure to meet global demand and consumption for fish in the next coming *** part address to this challenge,the purpose of this systematic review of literature(SLR)study is to investigate the use of the term‘market access’in its context of use in the generic literature and business sector discourse,in comparison to the more specific literature and discourse in fisheries,aquaculture and *** SLR aims to uncover the knowledge/interest gaps between the academic subject discourses and business sector *** driven in methodology and using a triangulation method of three different text analysis softwares including AntConc,VOSviewer and Web of Science(WoS)analytics,the SLR results indicate a gap in conceptual knowledge and business practices in how market access is conceived,studied and managed in the pharmaceutical and healthcare marketing industry in comparison to fisheries and ***'s complexity is directly acknowledged in the 2030 Agenda for Sustainable Development and Zero *** while the product orientation of different business sectors might differ,this SLR study works with the assumption that both business sectors are international in orientation,and complex in their operations from product to *** that extent,research scholars and practitioners in FAIB will need to broaden their efforts in understanding the multiplicity of forces that influences fisheries and aquaculture and its international orientation towards both emerging as well as mature *** SLR suggests a conceptual model in understanding the challenges,the potential barriers as well as avenues for solutions to developing market access for FAIB.

关键词： Market access fisheries and aquaculture International business Systematic literature review Concordance analysis Bibliometric analysis Research methods

Behaviour of rainbow trout(Oncorhynchus mykiss) under defensible and indefensible patterns of food delivery

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Chinese Journal of Oceanology and Limnology 2010年第4期28卷 749-755页

作者： M.SAEED HEYDARNEJAD G.J.PURSER aquaculture Sector Biology Dept.Faculty of ScienceShahrekord Uni. School of aquaculture Tasmanian Aquaculture and Fisheries InstituteUniversity of Tasmania

The goal of this study was to investigate the behaviour of rainbow trout(n=30),Oncorhynchus mykiss,in small raceways when either self-feeders(T2) or hand-feeding(t2) were *** method of food delivery in T2 was defensible while that of t2 was *** in both raceways were subjected to restricted feeding(RF) for 25 *** was available in the morning(09:00-10:00) in the downstream area and in the afternoon(16:00-17:00) in the upstream area of the *** results showed that the behaviour of rainbow trout was significantly different under interference competition(T2) for food compared with that under scramble competition(t2).RF in T2 fish limited food availability to meal times when feeding rewards were available while t2 fish only responded to the location of food *** aggressive fish in T2 were dominant,and t2 fish at high densities showed intense social interactions under the indefensible pattern of food distribution;these interactions did not dampen to a minimum level to suppress the development of dominance ***,the stocking density did not break down the dominance hierarchies between the T2 *** suggests that decreased efficiency in the search for food or inefficient foraging,induced by interference competition at high densities,affected the behaviour of rainbow trout.

关键词： rainbow trout defensible and indefensible pattern of food delivery dominant

Drag on Hydroid-Fouled Nets – An Experimental Approach

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China Ocean Engineering 2015年第3期29卷 369-389页

作者： Pl LADER David W. FREDRIKSSON Jana GUENTHER Zsolt VOLENT Nina BLOCHER David KRISTIANSEN Lars GANSEL Jud DECEW SINTEF fisheries and aquaculture united States Naval Academy University of New Hampshire

The present study investigated the drag increase on aquaculture nets due to biofouling of the colonial hydroid Ectopleura larynx. It had two main parts： firstly the growth characteristics of E. larynx were investigated by use of field tests at a Norwegian aquaculture site; secondly the hydrodynamic drag on the fouled twines was studied in a towing tank by using fabricated models of net twines with artificial hydroid fouling. In the field tests, the growth of the hydroids was first measured after three weeks of immersion and then again after six weeks. During this interval, the density of hydroids and the thickness of the hydroid stem were almost constant（1.4 hydroids/mm and 0.29 mm, respectively）, while the average length of the hydroids increased from 6.4 to 11.2 mm. The hydroid length followed a Rayleigh distribution, while the thickness was normal（Gaussian） distributed. Replicas of twines with three different levels of hydroid growth were made（1.5 hydroids/mm twine, hydroid length 9 mm, 16 mm and 20 mm）, and the drag on these twines was measured at different towing velocities（0.1 to 1.4 m/s） and with different twine configurations. For the twine with the shortest hydroids（9 mm）, the drag was from 1.5 times（Re=4000） to 2.2 times（Re=1000） the drag on a clean twine. For the longest hydroids（21 mm）, the drag was 2 times and 3.8 times, respectively.

关键词： hydroid biofouling aquaculture net hydrodynamic drag

Generation of Eco-Friendly and Disease-Resistant Channel Catfish(Ictalurus punctatus)Harboring the Alligator Cathelicidin Gene via CRISPR/Cas9 Engineering

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Engineering 2024年第8期39卷 273-286页

作者： Jinhai Wang Baofeng Su De Xing Timothy J.Bruce Shangjia Li Logan Bern Mei Shang Andrew Johnson Rhoda Mae C.Simora Michael Coogan Darshika U.Hettiarachchi Wenwen Wang Tasnuba Hasin Jacob Al-Armanazi Cuiyu Lu Rex A.Dunham School of fisheries Aquacultureand Aquatic SciencesAuburn UniversityAuburnAL 36849USA

As a precise and versatile tool for genome manipulation,the clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)platform holds promise for modifying fish traits of *** the aim of reducing transgene introgression and controlling reproduction,upscaled disease resistance and reproductive intervention in catfish species have been studied to lower the potential environmental risks of the introgression of escapees as transgenic *** advantage of the CRISPR/Cas9-mediated system,we succeeded in integrating the cathelicidin gene(As-Cath)from an alligator(Alligator sinensis)into the target luteinizing hormone(lh)locus of channel catfish(Ictalurus punctatus)using two delivery systems assisted by double-stranded DNA(dsDNA)and single-stranded oligodeoxynucleotides(ssODNs),*** this study,high knock in(KI)efficiency(22.38%,64/286)but low ontarget events was achieved using the ssODN strategy,whereas adopting a dsDNA as the donor template led to an efficient on-target KI(10.80%,23/213).The on-target KI of As-Cath was instrumental in establishing the lh knockout(LH^(–)_As-Cath^(+))catfish line,which displayed heightened disease resistance and reduced fecundity compared with the wild-type(WT)sibling ***,administration of human chorionic gonadotropin(HCG)and luteinizing hormone-releasing hormone analogue(LHRHa)can restore the reproduction of the transgenic fish ***,we replaced the lh gene with an alligator cathelicidin transgene and then administered hormone therapy to move towards complete reproductive control of diseaseresistant transgenic catfish in an environmentally responsible *** strategy not only effectively improves consumer-valued traits but also guards against unwanted introgression,providing a breakthrough in aquaculture genetics to confine fish reproduction and prevent the establishment of transgenic or domestic genotypes in the natural environment.

关键词： Genome editing ssODN dsDNA Antimicrobial peptide Reproductive confinement aquaculture

Intersexual plasticity in aspects of the biology of the mudskipper Periophthalmus barbarus (Gobhdae) in the mangrove swamps of IMO Estuary, Nigeria

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Journal of Environmental Sciences 2002年第1期14卷 95-101页

作者： Mfon T. Udo (Department of fisheries and aquaculture University of Uyo, PMB 1017, Uyo Akwa Ibom State, Nigeria.) Department of fisheries and aquaculture University of Uyo PMB 1017 Uyo Akwa Ibom State Nigeria

Between April 1992 and March 1993, intersexual plasticity in aspects of the biology of the mudskipper, Periophthalmus barbarus was studied. Sex was differentiated on the basis of the genital papillae, it was broader in females than males. Sexually active females were slightly heavier than similarly sized males. Sex ratio was strongly female biased. Length weight relationship of the sexes was isometric. There was no significant difference in the feeding intensity of both sexes; uniformity was also apparent in diet breadth. There was no named sex based difference in hepatosometic index but condition index was higher in males than females. The uniformity in intersexual plasticity of *** is consequent upon homogeneity of the mangrove ecosystem, which can only be altered anthropogenically.

关键词： intersexual plasticity Periophthalmus barbarus mangrove swamp length weight relationship feeding intensity

Acute toxicity of organochlorine insecticide endosulfan to the giant freshwater prawn Macrobrochium rosenbergii

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Chinese Journal of Oceanology and Limnology 2014年第1期32卷 111-119页

作者：戴习林熊昭娣谢剑丁福江 College of fisheries and Life Science Department of AquacultureShanghai Ocean University Shanghai Shencao Special fisheries Development Company

Endosulfan, an organochlorine pesticide, is highly toxic and effective at controlling pests in agriculture, horticulture, and public health programs. In this study, static bioassays were used to evaluate the toxicity of endosulfan to freshwater prawns( Macrobrachium rosenbergii) of various lengths(1.5±0.03,4±0.08, and 7±0.06 cm). Additionally, the activities of peroxidase(POD), acid phosphatase(ACP),alkaline phosphatase, acetylcholinesterase(AChE), and Na + /K +-ATPase were analyzed to refl ect the effects of endosulfan exposure. The 96 h LC 50 of endosulfan for prawns 1.5, 4, and 7 cm long were 1.86, 4.53,and 6.09μg/L, respectively, improved tolerance to endosulfan with growth. The POD activities of test organisms exposed to low concentrations of endosulfan were inhibited, indicating the presence of oxygen damaged tissue. Moreover, a notable decrease in AChE activity was observed due to overstimulation of neurotransmission, which might result in abnormal behavior. The effect caused by endosulfan on phosphatase production in the hepatopancreas of prawns 1.5, 4, and 7 cm long was different because the ability of nonspecifi c immune regulation increased with growth. The 96 h LC 50 values obtained in this study could be used in the formulation of water-quality criteria in China. Moreover, the changes in enzymes activities of M. rosenbergii under stress of endosulfan could be applied in the establishment of early warning indicators for bio-safety.

关键词： hepatopancreas acetylcholinesterase (ACHE) peroxidase (POD) alkaline phosphatase (AKP) acid phosphatase (ACP) Na+/K+-ATPase

Morphometric relationships and reproductive maturation of the mudskipper, Periophthalmus barbarus from subsistence catches in the mangrove swamps of IMO estuary, Nigeria

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Journal of Environmental Sciences 2002年第2期14卷 221-226页

作者： MFON T. UDO (Department of fisheries and aquaculture, Faculty of Agriculture, University of Uyo, PMB 1017, Akwa Ibom State, Nigeria. Department of fisheries and aquaculture Faculty of Agriculture University of Uyo PMB 1017 Akwa Ibom State Nigeria

From April 1992 and March 1993, morphometric characteristics and reproductive maturation were studied in Periophthalmus barbarus from subsistence catches in the mangrove swamps of Imo estuary. Morphometric equations for males and females at different stages of ovarian maturation are presented. Generally males were significantly heavier in weight than females, but the latter were heavier than the former of the same body length. Females with developing and mature ovaries were generally heavier than immature females of the same length. Analyses of the gonadosomatic index and percentage of mature males and females indicate all year\|round breeding such that: February\|May was spawning, June\|October postspawning and November to January recovery period. Fecundity varied between 900 and 23933 eggs per spawn and increased with fish size.

关键词： periophthalmus barbarus morphometric relationships reproductive maturation mangrove swamps Imo estuary Nigeria

Adhesion mechanisms of Vibrio fluvialis to skin mucus of Epinephelus awoara

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Chinese Journal of Oceanology and Limnology 2010年第2期28卷 260-266页

作者：鄢庆枇赵敏慧王晓露邹文政陈昌生 Key Laboratory of Science and Technology for aquaculture and Food Safety Fisheries College of Jimei University

Vibriofluvialis incubated in trypticase soy broth （TSB） showed stronger adhesion to the skin mucus of Epinephelus awoara than V. fluvialis grown on trypticase soy agar （TSA）, and this bacterial adhesion was assessed in terms of saturation kinetics. Treating bacteria with antibody against O-antigens resulted in significantly reduced bacterial adhesion. In the early growth stage, the adhering bacteria numbers increased with incubation time, peaked at 24 h, and then dropped sharply. Prior heat treatment of the mucus at various temperatures resulted in different effects on bacterial adhesion. No remarkable effect on bacterial adhesion was detected after treating mucus with protease K and trypsin, whereas periodic acid treatment significantly enhanced bacterial adhesion. Extracts of K fluvialis surface structures at high concentrations significantly inhibited bacterial adhesion, while relatively low concentrations enhanced adhesion. V. fluvialis had strong affinity for a high molecular weight mucus component. These results indicate that *** adhered strongly to E. awoara mucus by specific adhesion and that this adhesion was influenced by many factors, including bacterial conditions, mucus, and the environment.

关键词： Vibrio fluvialis Epinephelus awoara skin mucus adhesion