Open Journal of Fisheries Research
ISSN / EISSN : 2373-1443 / 2373-1451
Published by: Hans Publishers (10.12677)
Total articles ≅ 158
Latest articles in this journal
Open Journal of Fisheries Research, Volume 09, pp 13-19; https://doi.org/10.12677/ojfr.2022.91002
A rearing trial of juvenile Murray cod was conducted in Dongying coastal saline land. The initial average body weight was 0.30 ± 0.05 g. After 167 days of cultivation, the average body weight was increased to 51.2 ± 10.5 g with surviving rate of 71.7% and feed coefficient (FCR) of 0.82. It was preliminarily determined that juvenile Murray cod could adapt to the local groundwater environment and show good growth performance. This species was speculated to be one of the potential fish species for local large-scale farming in the future.
Open Journal of Fisheries Research, Volume 09, pp 1-12; https://doi.org/10.12677/ojfr.2022.91001
β-defensin is a small cationic antimicrobial peptide rich in cysteine, which plays an important role in innate immunity of the living organism. In this study, the β-defensin genes of Huangsha soft- shelled turtle (Hs-BDs) family were identified based on transcriptome database of Huangsha soft- shelled turtle and PCR validation, and the physicochemical properties of protein, protein structure and evolutionary relationship were also analyzed. The results showed that a total of 18 members of Hs-BDs family with complete coding regions were identified. The number of amino acid residues of these Hs-BDs proteins ranged from 59 to 94, the molecular weight ranged from 6759.13 to 10,731.32 Da, and the isoelectric point ranged from 8.82 to 10.45. The 18 members of Hs-BDs family were divided into four subgroups (Class I~IV) according to the phylogenetic tree analysis. Some Hs-BDs were randomly selected for protein structure analysis and the results showed that the secondary structures of Hs-BDs preprotein are mainly composed of α-helix, β-sheet and random coil. Six conserved cysteine residues were linked to form three intramolecular disulfide bonds in the form of Cys1-Cys5, Cys2-Cys4 and Cys3-Cys6, respectively. The results of this study can provide basic data for further research on the detailed functions of β-defensin gene family and the development of antimicrobial peptides.
Open Journal of Fisheries Research, Volume 09, pp 26-35; https://doi.org/10.12677/ojfr.2022.91004
The effects of temperature and pH on the activities of protease, amylase and cellulase in intestine and hepatopancreas of blood parrot were studied. The results showed that the digestive enzyme activity of blood parrot increased first and then decreased with the increase of temperature and pH. The optimum temperature of protease was 55˚C, 45˚C, amylase was 35˚C, 25˚C, cellulase was 45˚C. The optimal pH of protease was 8.0, 10.0, amylase was 7.0, and cellulase was 5.0. Under the optimum temperature, the order of the activity of blood parrot protease was intestine > hepatopancreas, the order of the activity of amylase was hepatopancreas > intestine; under the optimum pH, the order of the activity of blood parrot protease was hepatopancreas > intestine, the order of the activity of amylase was intestine > hepatopancreas.
Open Journal of Fisheries Research, Volume 09, pp 20-25; https://doi.org/10.12677/ojfr.2022.91003
Seahorse is a kind of precious marine medicinal teleosts with special father’s rearing pattern and gonadal structure. Analyzing the histological structure of seahorse gonads is significant of improvement in efficiency of artificial breeding. Compared with paraffin section, frozen section has a fast and simple operation, while the quality of which is susceptible to multiple factors. The fixative is a key factor for Hematoxylin-Eosin (HE) staining. In our study, we chose 8 kinds of fixatives for the frozen section of seahorse ovary and compared the quality of HE stain, results showed that glacial acetic acid fixation was an ideal fixative for frozen sections of seahorse ovary stained with HE, which displayed a clear tissue structure with distinct nuclear boundary, high nucleo-plasmic contrast and bright-coloured yolk granules.
Open Journal of Fisheries Research, Volume 08, pp 165-174; https://doi.org/10.12677/ojfr.2021.84020
The genetic structure of Coilia nasus was studied based on the sequences analysis of mitochondrial D-loop in 75 individuals from Liao River (n = 20), Dayang River (n = 27) and Yalu River (n = 28), Liaoning province. In 1130~1171 bp of D-loop sequences, there were 94 polymorphic sites and 60 haplotypes. The haplotype and nucleotide diversities were 0.992 ± 0.004 and 0.010 ± 0.000, respectively. AMOVA revealed 98.27% of the total variation was resulted from intra-population differentiation, there was little genetic differentiation among populations. Both NJ tree and MJ network of 60 haplotypes indicated there was no geographic structure among populations. Three populations of C. nasus should be considered as a genetic management unit. The findings may be very useful to protect this species stock.
Open Journal of Fisheries Research, Volume 08, pp 45-52; https://doi.org/10.12677/ojfr.2021.82005
本文通过在实验室条件下模拟方斑东风螺(Babylonia areolata)养殖池离底铺沙模式，对比了不同进水和排水方式对养殖池水更换效果的影响。结果表明，在上进下排类型中，不同进水方式对沙层下方水体的更换效果没有显著差异(P > 0.05)，不同排水方式对沙层下方水体的更换效果影响有显著差异，其中，中间单孔排水效果最好(P In this paper, the effects of different water inflow and outflow designs on water changing efficiency of Babylonia areolata farming pond were compared by simulating the sand-on-bottom-shelve model of Babylonia areolata farming pond under laboratory conditions. The results showed that there were no significant differences in water changing efficiency between different water inflow methods (P > 0.05), but there were significant differences between different outflow methods, and the middle single hole outflow design was most efficient in changing the water body under the sand layer (P < 0.05). The results also showed that the water changing speed of side wall outflow with reverse water seepage in-flow model is significantly faster than that of the middle single hole outflow model with single side water inflow (P < 0.05), but the water changing speed of the whole water body is slower than that of the middle single hole outflow with unilateral inflow model (P < 0.05). The middle single hole outflow with single side inflow model can effectively rinse the accumulated organic matters such as excreta, residual bait, ammonia nitrogen and hydrogen sulfide in the sand layer, and keep the sand layer clean.
Open Journal of Fisheries Research, Volume 08, pp 76-83; https://doi.org/10.12677/ojfr.2021.82009
在“绿水青山就是金山银山”绿色发展理念的践行下，中国的水产养殖业已经进入了崭新的发展时期，绿色高效的养殖技术层出不穷。而新时代下绿色高效养殖技术的关键在于循环水处理技术。循环水处理大致分为物理处理、化学处理、生物处理。虽然每种处理方法各有千秋，但是在整个循环水处理体系起着相辅相成的作用，各式新型的养殖模式也逐步得到发展。新时代下的水产养殖应做到“顺天时，量地利”，顺应新时代的绿色发展，因地制宜、取长避短，应用合理的养殖模式，寻求经济效益与绿色发展的最佳契合点，才能真正做到“用力少，成功多”。 China’s aquaculture industry has entered a new period of development under the practice of “Lucid waters and lush mountains are invaluable assets”, and green and efficient aquaculture technologies have emerged in an endless stream. The key of green and efficient aquaculture technology in the new era lies in circulating water treatment technology. Recirculating water treatment is roughly divided into physical treatment, chemical treatment and biological treatment. Although each treatment method has its own advantages and disadvantages, it plays a complementary role in the whole circulating water treatment system, and various new breeding modes have been gradually developed. Aquaculture should achieve “favorable weather, favorable geographical conditions” with adapting to the green development of the new era, adapting to local conditions, taking advantage of strengths and avoiding weaknesses. We can truly achieve “less effort and more success” by applying reasonable breeding mode and seeking the best coincidence point between economic benefit and green development.
Open Journal of Fisheries Research, Volume 08, pp 34-43; https://doi.org/10.12677/ojfr.2021.81004
为了说明有色金属矿区周边水体的食物安全问题，以地方特色食物——螺蛳为研究对象，通过采集当地有色金属矿区周边不同水体的螺蛳样品，并采集污染程度较轻或无污染水体中的螺蛳样品作对照，分别用原子吸收光谱法和原子荧光光谱法，测定其不同部位的重金属Cu、Cr、Zn和As的含量，并参照我国食品污染物限量标准，说明其食用部位是否存在食用安全风险。结果表明：1) 在检测的螺蛳样品重金属元素中，Zn的含量最高，Cu的含量次之，其不同部位重金属含量的平均大小排序为Zn > Cu > As > Cr；2) 不同重金属在螺蛳体内的累积量有差异，其中，Zn、Cu、As均为内脏团 > 足肌 > 外壳，而Cr则为外壳 >内脏团 > 足肌；3) 厂矿、城镇、人口密集村落、大型公共活动场所、旅游区和开发区、高强度劳动作业区，其周围区域水体螺蛳样品的重金属含量相对比较高；4) 采集的部分螺蛳样品，其食用部分的重金属含量超标，其中，铬的最大超标倍数为11.44，无机砷的最大超标倍数为3.10，前者超标情况比后者更严重。因此，长期食用有色金属矿区周边水体重金属含量超标的螺蛳及其制品，存在一定的安全风险。 In order to illustrate the food safety issues in the waters surrounding the non-ferrous metal mining area, the local special food, Bellamya quadrata was taken as the research object. By collecting B. quadrata samples from different water bodies around the local non-ferrous metal mining areas, and collecting the B. quadrata samples from the water with less pollution or non-polluted water as a control. The content of heavy metals Cu, Cr, Zn, and As in different parts of the B. quadrata was determined by atomic absorption spectrometry and atomic fluorescence spectrometry respectively, and with reference to the national food contaminants limit standards, it is indicated whether there are food safety risks in their edible parts. The results show that: 1) among the heavy metal elements in the B. quadrata samples, the content of Zn is the highest, followed by the content of Cu, and the order of the average content of heavy metals in different parts is Zn > Cu > As > Cr; 2) the accumulation amount of heavy metals in B. quadrata spiral is different, among them, Zn, Cu and As are visceral mass > foot muscle > shell, while Cr is shell > visceral muscle > foot muscle; 3) the heavy metal content of B. quadrata samples in the surrounding areas of factories and mines, towns, densely populated villages, large public activity places, tourism areas and development zones, and high intensity labor operation areas is relatively high; 4) the content of heavy metals in the edible parts of the collected B. quadrata samples exceeds the standard. The maximum limit multiple of chromium is 11.44, and the maximum limit multiple of inorganic arsenic is 3.10. The former is more serious than the latter. Therefore, long-term consumption of B. quadrata and their products with excessive weight metal content in the water surrounding non-ferrous metal mining areas poses a certain safety risk.
Open Journal of Fisheries Research, Volume 08, pp 84-94; https://doi.org/10.12677/ojfr.2021.82010
本实验利用室内模拟法，探究了种植绿狐尾藻(H组)、抛洒底改型微生态制剂(D组)和施用生石灰(S组)对罗非鱼养殖池塘水质和底质营养物含量变化的影响。结果发现：H组对底质中总氮、总磷的去除率最高，分别为32.91%、28.05%。实验期间H组水中的NH+4-N、NH-2-N和TN浓度整体小于其它实验组；S组的NH-2-N和TP浓度显著大于对照组(P +4-N和TN浓度前中期显著大于对照组(P In this experiment, the effects of Myriophyllum elatinoides Gaudich (Group H), modified microecological agent (Group D) and quicklime (Group S) on nutrient content in water and sediment of tilapia culture pond were studied by indoor simulation. The results showed that: Group H had the highest removal rate of total nitrogen and total phosphorus in the sediment, which were 32.91% and 28.05%, respectively. During the experiment, the concentrations of NH+4-N、NH-2-N and TN in the water of group H were generally lower than those of other experimental groups. The concentrations of NH-2-N and TP in group S were significantly higher than those in the control group (P +4-N and TN in the early and middle stages were significantly higher than those in the control group (P < 0.05). The nutrient concentration of group D was between group H and group S. The results of the study show that the three methods of improving sediment can reduce the total nitrogen and phosphorus content in the aquaculture pond. Among them, the H group planted with Myriophyllum elatinoides Gaudich had the best effect on removing nitrogen and phosphorus from the sediment, and had almost no effect on the concentration of nutrients in the water, and the comprehensive restoration effect was the best.
Open Journal of Fisheries Research, Volume 08, pp 127-135; https://doi.org/10.12677/ojfr.2021.83015
拖网是现代渔业主要作业方式之一，其中单船拖网是拖网渔业中最常见的作业方式。网板是单船拖网系统的重要属具，主要为拖网作业提供水平扩张力。本文通过水槽模型试验和数值模拟研究圆形曲面网板的水动力性能。通过数据处理，获得该网板的升阻力系数、升阻比以及压力中心系数等水动力参数，并根据数值模拟结果分析网板周围的流场流态。结果显示，该网板既有较大的升力系数，又有较高的升阻比，且该网板的曲面外形及导流板结构可有效延缓流的分离，从而增大网板的临界冲角；数值模拟结果与模型试验结果比较近似，对网板最大升力系数及最大升阻比的模拟误差均低于10%，且数值模拟可以有效预测网板的临界冲角。本文建议在条件允许的情况下，利用水槽试验与数值模拟方法开展网板水动力学性能研究。 Trawling is one of the main methods of modern fisheries, of which the single trawling is the common operation types. Otter board is the vital components of a single trawler system; it can provide the desired horizontal opening of a trawl net. In the present study, the hydrodynamic of a circular cambered otter board was studied using flume tank experiment and numerical simulation. The lift/drag coefficient, lift-to-drag ratio and center-of-pressure coefficient were obtained during the data processing, and the flow distribution around the otter board was analyzed according to the numerical results. It showed that the otter board had a good hydrodynamic performance for its high lift coefficient and lift-to-drag ratio, and the camber/deflector structure can delay the flow separation. Numerical simulation results showed a good agreement with experiment ones and could predict the critical angle of attack. Simulation errors the maximum lift coefficient and lift-to-drag ratio were under 10%. Given the otter boards are operated in water, it was suggested to apply both flume tank experiment and numerical simulation to study the hydrodynamic performance of otter board.