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1.
Although the survival rate of juvenile Pacific bluefin tuna Thunnus orientalis (PBT) during 30 days after stocking in sea net cages has been as low as approximately 50%, the reason for this high mortality is not clear. The dead fish were collected and counted during 30 days after stocking in a sea net cage, and the growth performance, stomach contents, and bone injury were investigated. Nearly half (47.9%) had died within the first 4 days. The total length and body weight of the dead fish were significantly smaller than those of the live fish, and the weight of the dead fish did not increase during the first 7 days. Approximately one-third of the dead fish (21.9–42.9% per day) had ingested inorganic matter such as wood or Styrofoam waste during the first 7 days, and 25.0–45.0% of the dead fish sampled per day showed poor growth. The daily ingestion rate of inorganic matter decreased dramatically from the eighth day, when the daily mortality rate decreased. The percentage of dead fish with bone injuries due to collision or contact was low (less than 15%). These results suggest that one of the causes of high mortality during several days after stocking in a sea cage was accidental ingestion of inorganic matter by juvenile PBT. Improvement in feeding method can increase the survival rate of juveniles in sea net cages. 相似文献
2.
于2009年4月至2010年11月在平均水深18m、流速0.7m/s的福建省罗源湾岗屿海区,采用2口(c/)12.8m、入水深10m的深水网箱放养 110.3g/尾规格鱼种进行大黄鱼养殖试验.经19个月养殖,平均规格达到597.5g/尾,养成成活率约43.7％.试验结果表明:相对小网箱养殖,大黄鱼深水网箱养殖成品鱼体色... 相似文献
3.
Pacific abalone (Haliotis discus hannai Ino) aquaculture is a thriving industry in China. This study describes a novel submerged cage culture system for abalone rearing in Fujian, South China. The cage consisted of five vertical slots that were oriented perpendicular to the flow of water. The slots were separated by six vertically connected plastic plates for abalone attachment and shelter at the bottom of the cage. Experiment 1 was designed to determine the appropriate stocking density at the start of the abalone sea‐based production cycle. Eight‐month‐old hatchery reared and size‐graded juveniles were transferred to the sea‐based culture system. For different stocking densities, shell length of juveniles obtained in this novel culture system on 2, 3.5 and 5 months, respectively, was compared with shell lengths obtained in a traditionally multi‐tier basket culture system. In Experiment 2, daily growth rates (DGRs) in shell length and biomass in terms of wet weight of 2‐year‐old abalones reared in cage and tiered basket culture systems were compared over a 6‐month period. Results of Experiment 1 showed that growth of abalone in the cage culture system is density‐dependent; the mean final shell length of juveniles obtained was 6.7–15.9% higher than in tiered baskets system even at the same initial stocking density. In Experiment 2, DGRs in shell length of 53.83–78.38 μm day?1 obtained in cage system were significantly higher than that in tiered baskets (P < 0.01). And in terms of wet weight biomass, it was 1.48–3.01 times higher in the cage system compared with the traditional system. Abalone survival was more than 87.5% in both culture systems in both experiments. Advantages of the newly established cage culture system included better growth performance of the animals reared and potential improvement of rearing conditions, such as improved water flow velocity and dissolved oxygen. 相似文献
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5.
The Calafia mother‐of‐pearl oyster, Pinctada mazatlanica (Hanley), and the Rainbow nacre shell, Pteria sterna (Gould), represent an important resource for México because of their potential in pearl production. The present work deals with the effect of different sequences of nursery culture‐late culture on growth and survival of P. mazatlanica, from September 1993 to October 1994. The collected spat presented two main size groups: small (mean shell height of 7 mm), and large (13 mm). They were arranged into four experimental batches for each size group at a constant stocking density of 40–45 juvenile pearl oysters per Nestier cage. Three batches remained in nursery culture for 2, 4 and 6 months respectively, after which they were transferred to late culture in rail cages. A control group remained in nursery culture for 12 months. Growth was evaluated monthly and compared through anova and HSD Tukey tests. In addition to the shell height, width, depth (mm) and weight (g), data of shell volume (height × width × depth, in mm3) was also introduced to estimate and compare growth among the experimental groups. Mortality was estimated by counting the dead specimens every month and obtaining the percentage from a 100% initial survival at the start of the experiment. The juveniles showed different responses to the change from nursery culture to late culture; the level of each response varied significantly among the experimental groups at the end of the study. It seemed that a 6‐month period for nursery culture was propitious for P. mazatlanica. 相似文献
6.
Growth and mortality of the king scallop, Pecten maximus, werecompared when grown in cages and by ear hanging in suspended culturein Fuengirola, Malaga, in southern Spain. Seed (juveniles) used in theexperiment was collected in September 1997 that had settled on collectorsin April-June, of that year. Culture in suspended cages began in January1998 when the seed measured 42.7 (3.3) mm shell height and ended inFebruary 1999. Significantly faster growth was found at a minimum culturedensity (16 scallops/cage) than at two other densities (24 and 36scallops/cage). Depth (1, 5 and 10 m from the bottom) influenced growth,poorest growth occurred closest to the bottom. Under optimum growingconditions, 16 scallops/cage suspended 10 m from the bottom, scallops grewto 10 cm shell length (legal size) by February 1999.In ear hanging culture, ropes were moored in April (51.3 (4.5) mm),June (58.2 (4.5) mm) and November 1998 (64.3 (4.9) mm).Initially, rapid shell growth was observed in all three cultures.Subsequently, the shells became covered with barnacles, Balanus sp.,that possibly caused total mortality of the April culture and led to highmortalities in the two other cultures. 相似文献
7.
笼具形状对选育合浦珠母贝幼贝生长的影响 总被引：1，自引：0，他引：1
2011年8月,以海南三亚亲贝(♀)×广东徐闻亲贝(♂)构建的第一代选育合浦珠母贝(Pinctadafucata)群体为材料,研究长方形、圆柱形和半球形笼具形状在不同水深对合浦珠母贝幼贝(平均壳长1.4 cm)生长的影响。结果表明,长方形笼具在4 m水深时,幼贝的壳高和体重增长率最大,分别为24.55%和6.44%,显著高于其它水层(P<0.01);半球形笼具在3 m水深时,幼贝壳高和体重增长速度最大,分别为22.55%和5.40%,与其它水深的差异极显著(P<0.01);圆柱形笼具在6 m水深时,壳高和体重增长最快,增长率分别为22.46%和5.37%,显著高于3、5、7 m水深组(P<0.01),而与其余深度组差异不显著。此外,圆柱形笼具的高对合浦珠母贝的生长也有影响,在3 m水层20 cm高的圆柱形笼具中贝壳高和体重增长速度最大(增长率分别为24.70%和6.20%),与5、10、15 cm高度组差异显著(P<0.05);而长方形笼具虽然10 cm高的笼具较好,但与其它各实验组差异并不显著(P>0.05)。综合来看,合浦珠母贝在3～4 m水层用半径11.5 cm、高20 cm的圆柱形笼具或20 cm(长)×12 cm(宽)×10 cm(高)的长方形笼具养殖效果较好。但在制作成本方面,圆柱形笼具的成本低于长方形笼具。 相似文献
8.
Weijie Zhang Xiaohui Chen Huijie Jiang Zhong Wang Baofeng Wang Yaoyao Zhan Shoubing Qi Yaqing Chang 《Journal of the World Aquaculture Society》2019,50(5):969-982
To investigate the effects of family, stocking density, and their interaction on mortality, growth rate, and size dispersal in the sea urchin Strongylocentrotus intermedius, 1,440 juveniles from six full‐sib families were exposed to three stocking densities, that is, low stocking density (LD), middle stocking density (MD), and high stocking density (HD), and reared for 10 months in sea‐based suspended cages. The results demonstrated significant family effects on cumulative mortality rate (CMR); specific growth rate for test diameter (SGR for TD); specific growth rate for body weight (SGR for BW); coefficient of variation for body weight at the 10th month (CV for BW10); and significant stocking density effects on SGR for TD, SGR for BW, and CV for BW10. Statistically significant family by stocking density interaction was only found in SGR for TD. A certain degree of family‐ranking inversions occurred in SGR for TD. The present study provides evidence for the existence of family by stocking density interaction on the growth rate of test diameter in the family selection for S. intermedius. More attention should be paid to this interaction effect to select correct parents in S. intermedius. 相似文献
9.
Woo-Seok Gwak 《Aquaculture Research》2003,34(15):1387-1390
Black sea bass Centropristis striata (L.) juveniles were reared in aquaria containing either shelter or no shelter to investigate the effects of shelter on growth and survival. The specific growth rates of juveniles were significantly higher in the sheltered aquaria. With shelter present, the average mortality of juveniles caused by agonistic behaviour was 44% compared with no mortality in the unsheltered aquaria. The results provide evidence that shelter is advantageous for growth, but not survival of black sea bass juveniles under culture conditions. 相似文献
10.
Daniel D. Benetti Jaime A. Matera Owen M. Stevens Jorge F. Alarcon Michael W. Feeley Federico J. Rotman Yoichi Minemoto Gill Banner-Stevens Janice Fanke Scott Zimmerman Loyal Eldridge 《Journal of the World Aquaculture Society》2002,33(3):349-357
Abstract.— The aquaculture performance of mutton snapper Lutjanus analis raised in floating net cages was assessed by measuring their growth, survival, and feed conversion rates during a growout trial conducted in a 3.2‐ha saltwater lake in the Florida Keys, Florida, USA. Approximately 10,500 hatchery‐reared finger‐lings were stocked in two circular, high‐density polyethylene (HDPE) net cages of 7‐m diameter × 7‐m deep (300 m2) and 10‐m diameter × 7‐m deep (600 m3) dimensions. Cages were stocked at 25 fish/m3 (3.2 kg/m3) and 5 fish/m3 (0.72 kg/m3), respectively. Fish grew from a mean of 16.5 g to 302.8 g (25.6 cm TL) in 246 days in the former cage and from a mean of 42.3 g to 245.6 g (23.8 cm TL) in 178 d in the latter cage. Growth rates in weight were best expressed by the following exponential equations: cage 1 (high stocking density): W = 20.716 e0.0112x (r2= 0.83); cage 2 (low stocking density): W = 38.848 e0.0118x (r2= 0.81). Length‐weight data indicate that hatcheryraised, cage‐cultured mutton snapper are heavier per unit length than their wild counterparts. There was no significant difference (P < 0.05) between the slopes of the two lines, indicating that fish in the two cages grew at the same rate. The length‐weight relationships for mutton snapper stocked in cages 1 and 2 are expressed, respectively, by the equations W = 0.000009 L 3.11 (r2= 0.99) and W = 0.000005 L 3.22 (r2= 0.97). Overall feed conversion rate for both cages combined was 1.4. Approximately 10% of the fish sampled exhibited some degree of deformity, particularly scoliosis. Overall survival rate was 70%. Results suggest that L. analis has potential for aquaculture development in net cage systems. 相似文献
11.
Heidi Moe Tim Dempster Leif Magne Sunde Ulf Winther & Arne Fredheim 《Aquaculture Research》2007,38(1):91-99
Escapes of cod (Gadus morhua) from sea cages represent an economic problem for farmers and a potential environmental problem. We estimate that 0–6% of cod held in sea‐cage farms in Norway were reported to have escaped each year from 2000 to 2005, which is a high proportion compared with salmon. We interviewed employees at 19 coastal sea‐cage cod farms in Norway to investigate both how and why cultured cod escape and to document cage handling and management strategies that were effective in minimizing escapes. Based on the interviews, we describe five working hypotheses that may explain why a greater proportion of cod than salmon escape: (1) cod are more willing to escape than salmon; (2) cod bite the net cage and create wear and tear; (3) net cages have insufficient technical standards for cod culture; (4) cod are placed in sea cages at considerably smaller sizes than salmon; and (5) cod are more popular feed for predators. Preliminary testing of the hypothesis that cod bite netting and create holes was done by placing pre‐damaged net panels with cut twines and control panels inside sea cages. Holes in the pre‐damaged net panels increased in size over a period of 3 months. The type of damage indicated that biting of netting twines was the likely cause. 相似文献
12.
不同规格和投苗密度对仿刺参池塘网箱保苗效果的影响 总被引：2，自引：0，他引：2
仿刺参室外池塘网箱保苗是近年来兴起的一种半生态式的保苗方式。于2014年7—11月在仿刺参室外池塘网箱保苗期间,通过现场试验比较研究了不同投苗规格[大规格(0.093±0.004)g/头,小规格(0.024±0.001)g/头]和密度(低密度125g/m3、中密度250g/m3、高密度375g/m3)两因素对仿刺参苗生长、成活率和产量的影响。结果表明,对于同一规格的仿刺参苗,低密度组体质量与特定生长率高于中、高密度组;相同密度条件下,大规格苗种成活率显著高于小规格(P0.05),小规格低密度组仿刺参苗的成活率显著高于高密度组(P0.05),大规格低密度组仿刺参苗的成活率显著高于中、高密度组(P0.05)。不同密度组收获仿刺参苗的总产量无显著差异(P0.05),但低密度组收获仿刺参苗的净产量高于中、高密度组。通过两因素方差分析可知,规格的主效应及二者的交互作用对仿刺参苗成活率有显著的影响(P0.05),密度的主效应对仿刺参苗成活率有极显著的影响(P0.001);两因素的主效应及其交互作用对仿刺参苗总产量均无显著的影响(P0.05)。规格主效应及二者的交互作用对仿刺参苗净产量的影响不显著(P0.05),密度主效应对仿刺参苗净产量有显著的影响(P0.05)。因此,仿刺参室外网箱保苗过程中投放大规格、低密度苗种能够保证较高的成活率和净产量,而且可以节省苗种资源和饵料投喂量,降低单位面积生产成本和管理成本,提高产出投入比和经济效益。 相似文献
13.
以褐牙鲆(Paralichthys olivaceus)和大菱鲆(Scophthalmus maximus)为养殖对象,设计了2种新型的鲆鲽类网箱,即新型塑胶环保型单、双层网箱。通过褐牙鲆和大菱鲆网箱养殖实验来验证2种新型的网箱在实际生产中的可行性。结果显示,褐牙鲆传统木箱养殖组的商品鱼成活率为92.73%,单位面积产量为16.42 kg/m~2;塑胶单层网箱养殖组的成活率为96.37%,单位面积产量为17.42 kg/m~2。2个组的成活率、单位面积产量均存在显著差异(P0.05),单位面积产量同比增产6.10%。小规格大菱鲆传统网箱商品鱼成活率为92.50%,单位面积产量为8.09 kg/m~2;塑胶单层网箱组的商品鱼成活率为92.50%,单位面积产量为8.02 kg/m~2;塑胶双层网箱组的商品鱼成活率为92.00%,单位面积产量为10.53 kg/m~2,与传统网箱、单层塑胶网箱存在显著差异(P0.05),且同比增产分别为30.00%、31.00%。大规格大菱鲆单、双层塑胶环保型网箱养殖的成活率达到95.00%以上,单位面积产量均为14.52–16.32 kg/m~2;大规格大菱鲆双层网箱实验组平均尾重与单层网箱示范组差异显著(P0.05),单位养殖面积产量同比单层网箱示范组增产11.00%。研究表明,新型塑胶环保网箱养殖褐牙鲆效果良好。新型网箱相对于传统木制网箱除了具有节能环保、节约资源、操作便利的特点外,双层网箱养殖可提高有效利用面积,增加养殖效益。 相似文献
14.
The feasibility of co‐culturing the sea cucumber Holothuria leucospilota Brandt in a subtropical fish farm was investigated in a field study. Sea cucumbers were cultured in the fish farm in cages suspended at 4 m deep (suspended culture) and directly on the seafloor (bottom culture). The survival and growth of the sea cucumbers were monitored twice during the 3‐month, summer experimental period (May 26–August 14, 2010). Results showed that the suspension‐cultured sea cucumbers exhibited excellent survival rate (100%) during the whole study period. There also occurred no mortality in the bottom‐cultured sea cucumbers during the first culture period (May 26–July 13); but all these died from anoxia caused by water column stratification during the second culture period (July 14–August 14). The specific growth rate of the bottom‐cultured sea cucumbers (1.05 ± 0.21 % day?1) was nearly double that of the suspended culture animals (0.57 ± 0.21 % day?1) during the first culture period, and the growth rates of the suspended culture sea cucumbers in the second culture periods (0.46 ± 0.24 % day?1) was only a little lower than that of the first period. The sea cucumbers H. leucospilota could ingest and assimilate sediment with high organic matter content with an average assimilation efficiency of 14.9 ± 3.9%. This study indicated that fish farm detritus can be effectively used as a food source for the sea cucumber and that it can be turned into a valuable secondary crop in the form of the sea cucumber biomass. 相似文献
15.
Eduard M Rodriguez Fe D Parado-Estepa & Emilia T Quinitio 《Aquaculture Research》2007,38(14):1588-1592
To address the preference of mud crab farmers for larger size Scylla serrata juveniles (5.0–10 g body weight or BW; 3.0–5.0 cm internal carapace width or ICW), a study was conducted to compare the growth and survival of crab juveniles (2.0–5.0 g BW; 1.0–3.0 cm ICW) produced a month after stocking of megalopae in net cages when reared further in net cages installed in earthen ponds or when stocked directly in earthen ponds. In a 3 × 2 factorial experiment, three stocking densities (1, 3 and 5 ind m−2), two types of rearing units (net cages or earthen pond) were used. Megalopae were grown to juvenile stage for 30 days in net cages set inside a 4000 m2 brackishwater pond and fed brown mussel (Modiolus metcalfei). Crab juveniles were then transferred to either net cages (mesh size of 1.0 mm) or earthen ponds at three stocking densities. After 1 month, no interaction between stocking density and rearing unit was detected so data were pooled for each stocking density and rearing unit. There were no significant differences in the growth or survival rate of crab juveniles across stocking density treatments. Regardless of stocking density, survival in net cages was higher (77.11±6.62%) than in ponds (40.41±3.59%). Growth, however, was significantly higher for crab juveniles reared in earthen ponds. The range of mean BW of 10.5–16.0 g and an ICW of 3.78–4.33 cm obtained are within the size range preferred by mud crab operators for stocking grow‐out ponds. 相似文献
16.
2016年3月6日—5月3日,在福建省漳浦县霞美镇浮头湾外海域进行三种不同结构鲍匍匐基养殖对比试验。三种鲍匍匐基分别为扣箱式(有效匍匐面积1.072 8 m2)、双层斜板式(有效匍匐面积1.993 5 m2)和传统养殖盆(有效匍匐面积0.413 3 m2),试验对象为皱纹盘鲍杂交鲍(Haliotis discus hanai)。试验结果如下:1)扣箱式鲍壳长日增长为0.131mm,日增重为0.129 g,存活率为98.44%,饲料转化率为3.38%;2)双层斜板式鲍壳长日增长为0.098 mm,日增重为0.096 g,存活率为99.38%,饲料转化率为4.29%;3)传统养殖盆式鲍壳长日增长为0.115 mm,日增重为0.103 g,存活率为98.00%,饲料转化率为5.37%。试验设施未受到湾外海况影响破坏。结果表明扣箱式鲍匍匐基整体性能较好,基于该匍匐基的鲍养殖网箱在经济型吊杆辅助作业下具有养殖效率高、抗风浪流性好、劳动强度低、所需劳动力少等优点,适合应用于湾外养殖。 相似文献
17.
Growth,Survivorship, Air‐bubble Disease,and Attachment of Feeble Juvenile Seahorses,Hippocampus kuda (Bleeker, 1852) 
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下载免费PDF全文 Yanhong Zhang Geng Qin Junda Lin Qiang Lin 《Journal of the World Aquaculture Society》2015,46(3):292-300
Seahorse aquaculture has been a focus for meeting the demand of traditional medicine and aquarium. Feeble (poor quality) juveniles are commonly found in the commercial seahorse culture. In this study, we compared the growth and survival performances of the feeble and healthy common seahorses Hippocampus kuda. The results show that the feeble juveniles had high growth and survival at the temperature of 27–29 C and salinity of 26–28‰ with frequent feeding (≥three times a day) during first 5 wk. Through a 12‐wk investigation, we found that the air‐bubble disease could significantly affect the specific growth rate and survival of the feeble juveniles. There was a positive and significant correlation between the substrate‐attachment rate and survival rate in the feeble juveniles, and substrate‐attachment rate may be used to assess the quality of the feeble populations in the seahorse H. kuda. 相似文献
18.
Itzel A. Snchez‐Tapia Matthew Slater Miguel A. Olvera‐Novoa 《Journal of the World Aquaculture Society》2019,50(4):763-773
Isostichopus badionotus is a new commercially important sea cucumber in the Caribbean that has rapidly shown signs of overexploitation. There is no information on the growth and survival rates for wild or hatchery‐produced early juveniles. Hatchery production and determination of juvenile growth rates are essential for future aquaculture efforts for this species. In this study, daily growth rate (GR), specific growth rate (SGR), weight gain (WG), survival rate (SR), and weight–length relation (WLR) were evaluated using small (0.01 g) and large (0.25 g) hatchery‐produced early juveniles under laboratory conditions. Growth was rapid compared to other cultured sea cucumber species; maximal values of SGR and WG were obtained for small juveniles (4.58%/day and 2,191%, respectively), while maximal GR and SR were obtained for large juveniles (0.29 mm/day and 99.17%, respectively). A wide range of sizes was evident at the end of each trial. The WLR of small and large juveniles fit with a negative allometric growth trend. This study highlights the potential production of I. badionotus as early juvenile stages withstand hatchery handling well and exhibit a high SR, reaching commonly released mean sizes (>0.7 g and 25 mm) after almost 3 months (120 days postfertilization). 相似文献
19.
Scale matters: performance of European sea bass,Dicentrarchus labrax,L. (1758), reared in cages of different volumes 下载免费PDF全文
下载免费PDF全文 Athanasios Samaras Michael Pavlidis Konstadia Lika Antonia Theodoridi Nikos Papandroulakis 《Aquaculture Research》2017,48(3):990-1005
The effects of rearing volume on on‐growing European sea bass performance and stress parameters were investigated for the first time in a pilot aquaculture farm. Fish were held under the same initial stocking densities in triplicate net‐pen cages of different sizes (1.4, 45 and 252 m3) for a period of 8 months. Results showed significant differences among the experimental groups in most parameters tested, with better performance in the two larger rearing volumes. In particular, growth rate showed a linear association with rearing volume, being 0.68 g day?1 for the large cage group, 0.56 g day?1 and 0.32 g day?1 for the medium and the small groups respectively. The feed conversion ratio and per cent survival (%) were also better in the large cage group. Fish reared in the small and medium‐sized cages showed higher plasma cortisol concentrations than those reared in large cages, which showed low basal cortisol concentrations. Additionally, after an acute chasing stress challenge, fish in the large and small groups, but not the medium group, showed increased cortisol concentrations. Differences also occurred in the ratio of the expression of cortisol receptors, namely the mineralocorticoid (mr) and glucocorticoid receptors (gr). In specific, the ratio of mr to grmRNA expression in the liver was higher in fish reared in the small cages. These findings verify that experimental scale significantly affects experimental results and is a critical factor for the interpretation of results. 相似文献
20.
虾夷马粪海胆的海区渡夏、室内中间培育及工厂化养成↑（*） 总被引：3，自引：0，他引：3
１９９３年７月～１９９７年５月,在夏季采用网袋、网箱开展虾夷马粪海胆Ｆ２代稚海胆的海区渡夏,壳径日平均生长量比室内提高３３．６％～６１．６％;采用网箱平面培育方法进行Ｆ２代稚海胆室内中间育成和Ｆ３代稚海胆室内中间育成中试,壳径的日平均生长量随时间呈下降趋势,为０．５３×１０－２～１．４６×１０－２ｃｍ／ｄ,体重日平均生长量呈上升趋势,介于２．３２×１０－２～１０．７２×１０－２ｇ／ｄ之间,培养中密度过大会降低海胆的成活率并导致疾病发生;采用立体水槽开展陆地工厂化养成,经１３个月,海胆壳径由１．１６ｃｍ增至５．９８ｃｍ,体重由０．４７ｇ增至６１．０ｇ,性腺指数达１８．０％。 相似文献