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1.
渔光一体池塘光伏区和非光伏区中华绒螯蟹二龄蟹的养殖生长比较 总被引：1，自引：0，他引：1
《淡水渔业》2021,51(3)
为了解渔光一体模式下中华绒螯蟹(Eriocheir sinensis)池塘养殖生长规律,在渔光一体池塘内,分别在光伏覆盖区域和非光伏覆盖区域开展中华绒螯蟹养殖实验,比较光伏区和非光伏区中华绒螯蟹二龄蟹的生长情况。结果显示,6月份之前,非光伏区中华绒螯蟹显示出一定的生长优势,6月份之后光伏区中华绒螯蟹的生长优势突出,生长速度和规格均明显超过非光伏区,且光伏区最终的养成规格、产量(高13.06个百分点)、成活率(高6.2个百分点)等均体现出明显优势。实验结果证实了光伏遮光对河蟹养殖具有显著优势。 相似文献
2.
采用红色可视嵌入性荧光(visible implant elastomer,VIE)标记中华绒螯蟹(Eriocheir Sinensis),观察了荧光标记在中华绒螯蟹中的保持率和对其存活、生长、发育及繁殖的影响。荧光标记幼蟹不同部位在室内饲养并观察8周,结果表明,在中华绒螯蟹幼蟹不同部位的标记保持率均为100%,对照组和各试验组幼蟹的存活率无显著性差异(P0.05)。荧光标记幼蟹螯掌节和腕节间的关节膜后移入室外养殖池养殖,中华绒螯蟹室外养殖的生长和发育速度与对照组也无显著差异(P0.05)。挑选标记后经室外池塘养成的中华绒螯蟹进行小水体繁育实验,抱卵率为83.3%,平均抱卵量30×104egg·ind-1,与未标记中华绒螯蟹小水体繁育实验结果比较,抱卵率、平均抱卵量无显著性差异,荧光标记不影响中华绒螯蟹交配抱卵。本文结果表明,VIE可视荧光标记可作为中华绒螯蟹个体识别标记,应用于育种、资源调查等研究和生产实践。 相似文献
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为测定生长与新陈代谢对不同规格中华绒螯蟹幼蟹和不同组织碳稳定同位素周转速率的影响及分馏系数，本在水族箱（0.2 × 0.2 × 0.3 m）中分别养殖EA组（4.0 g ± 0.5 g）和EB组（15.5 g ± 0.5 g）2组中华绒螯蟹幼蟹，分别于0、7、14、21和28 d时采集幼蟹的肝胰腺、肌肉和鳃组织，探究其碳稳定同位素周转过程，并测定了幼蟹对食物碳、氮稳定同位素的分馏系数。结果显示，EA组幼蟹碳稳定同位素的周转速率大于EB组，周转速率随着幼蟹规格的增大而减小。幼蟹肝胰腺的周转速率最快，其次是肌肉，最后是鳃，其中EA组幼蟹肝胰腺、肌肉和鳃的半衰期分别为20.88、29.37和34.14 d，EB组分别为21.73、35.18和66.01 d。新陈代谢是驱动幼蟹体内碳稳定同位素周转的主要因子，幼蟹肝胰腺、鳃和肌肉中新陈代谢占碳稳定同位素周转的贡献百分比分别为79.82% ~ 94.04%、（67.00% ~ 81.90%和71.61% ~ 90.36%。幼蟹对饵料碳、氮稳定同位素的分馏系数分别为0.98‰ ± 0.19‰和3.01‰ ± 0.02‰。本研究不仅对中华绒螯蟹幼蟹的营养生态学研究提供参考，还为中华绒螯蟹养殖过程中的饵料选择提供了科学依据。 相似文献
4.
中华绒螯蟹也称为河蟹,属于我国比较名贵的淡水蟹,中华绒螯蟹细菌性疾病具有发病比较快和死亡率较高等特点,会造成比较大的经济损失。对池塘养殖中华绒螯蟹出现的常见细菌性疾病的症状及流行特点进行了归纳,同时提出了防治方法。从而有效加强疾病预防和防治。 相似文献
5.
为了探索在上海崇明地区养殖大规格中华绒螯蟹成蟹的技术,在崇明西北部地区选择具有代表性的养殖池塘开展种草生态养殖成蟹试验。试验池塘面积15亩(15亩=1 hm2,下同),放养规格为100只/kg的中华绒螯蟹蟹种500只/亩,试验期间池塘整体水草覆盖率约为70%。试验结果:养殖成蟹871.95kg,亩产58.13 kg,其中雄蟹平均壳长64.23 mm,壳宽72.03 mm,体质量194.07 g,个体200 g以上的比例为40.0%;雌蟹平均壳长60.46 mm,壳宽67.51 mm,体质量140.88 g,个体150 g以上的比例为36.7%。结果表明,采用种草生态养蟹模式,可以在崇明地区养成大规格中华绒螯蟹,该模式是一种可持续发展的水产养殖模式。 相似文献
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螺蛳投放量对中华绒螯蟹规格、产量和成活率的影响 总被引：8，自引：0，他引：8
研究了螺蛳投放量对池塘生态养殖的中华绒螯蟹平均育成规格、产量和成活率的影响.结果表明,中华绒螯蟹产量(Z)与螺蛳投放量(x)的关系为:Z=528.138+0.228x-0.000029x~2(R~2=0.959)(P＜0.05);中华绒螯蟹规格(Y)与螺蛳投放量(x)的关系为:Y=155.368+0.014x-0.0000017x~2(R~2=0.934)(P＜0.05);中华绒螯蟹成活率与螺蛳投放量的关系为:L=52.208+0.018x-0.0000023x~2(R~2=0.957)(P＜0.05).中华绒螯蟹池塘生态养殖中螺蛳最佳投放量为4500 kg/hm~2. 相似文献
9.
欧、美中华绒螯蟹源于中国长江水系中华绒螯蟹的遗传证据 总被引：8，自引：0，他引：8
用包括Z2和Opp17两个10碱基随机引物在内的10个引物,对来自荷兰斯科克莱（Skodely)、美国加州圣何塞（San Jose)的中华绒螯蟹群体与中国长江水系中华绒螯蟹群体进行RAPD遗传比较分析。结果发现：（1）中华绒螯蟹群体特有的Z2引物扩增的700bp标记带（Z2^700bp）,在荷兰与美国2个中华绒螯蟹群体中同时出现,而不出现日本绒螯蟹南流江种群中特有的880bp标记带（Z2^880bp）,表明欧洲、美国中华绒螯蟹与中国中华绒螯蟹为同种Eriocheir sinensis,而非日本绒螯蟹Eriocheir japonicus;（2）Opp17引物扩增的947bp片段在中国长江、荷兰及美国3个中华绒螯蟹群体内的出现频率均达100%。结合Z2引物扩增结果,欧洲与美国中华绒螯蟹群体极可能是从中国长江水系中华绒螯蟹引入繁衍的。 相似文献
10.
为分析辽东湾海水生态养殖池塘仿刺参的食性特征,分别于2016年3月、5月、7月、9月、12月采集池塘中的浮游植物、浮游动物、颗粒有机物、底栖硅藻、表层底泥和仿刺参,并检测所有样品的δ13C和δ15N值。运用IsoSource线性混合模型计算出浮游植物、浮游动物、颗粒有机物、底栖硅藻、表层底泥对仿刺参的饵料贡献率。试验结果显示,底栖硅藻对仿刺参的平均饵料贡献率周年变化为78.5%～85.7%,颗粒有机物、浮游植物、浮游动物和表层底泥对仿刺参的贡献率分别为2.1%～5.1%、2.2%～5.6%、2.3%～7.7%、3.6%～7.9%。底栖硅藻对消化管内含物δ13C值的贡献率为25.8%～74.5%、颗粒有机物、浮游植物、浮游动物和表层底泥对消化管内含物δ13C值的贡献率分别为3.9%～15.3%、4.0%～18.3%、4.2%～19.4%、5.6%～22.2%。试验结果表明,在不投饵、缺乏底栖大型藻类的生态养殖池塘中,底栖硅藻是仿刺参主要的食物来源,仿刺参也摄食表层底泥、沉降后颗粒有机物和浮游动植物。研究结果可为海水池塘仿刺参的生态健康养殖提供基础数据。 相似文献
11.
中国在2007～2008年的国际粮食危机中没有受到冲击，主要原因是中国已经建立了较为健全的粮食安全系统，具有较低的粮食对外贸易依存度。但仍存在着一些制约粮食安全的因素和隐患，中国利用国际粮食市场虽然在经济上具有可行性，但是国际粮源的可供性、政治上的可靠性、国际规则的有效性都难以保障。因此坚持95％的粮食基本自给政策，实施“宽进严出”策略，完善粮食贸易管理措施，实施粮食进口贸易伙伴国的多元化，就成为中国粮食对外贸易政策的基本选择。 相似文献
12.
Aquatic food security: insights into challenges and solutions from an analysis of interactions between fisheries,aquaculture, food safety,human health,fish and human welfare,economy and environment 
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下载免费PDF全文 Simon Jennings Grant D Stentiford Ana M Leocadio Keith R Jeffery Julian D Metcalfe Ioanna Katsiadaki Neil A Auchterlonie Stephen C Mangi John K Pinnegar Tim Ellis Edmund J Peeler Tiziana Luisetti Craig Baker‐Austin Mary Brown Thomas L Catchpole Fiona J Clyne Stephen R Dye Nathan J Edmonds Kieran Hyder Janette Lee David N Lees Owen C Morgan Carl M O'Brien Birgit Oidtmann Paulette E Posen Ana Ribeiro Santos Nick G H Taylor Andrew D Turner Bryony L Townhill David W Verner‐Jeffreys 《Fish and Fisheries》2016,17(4):893-938
Fisheries and aquaculture production, imports, exports and equitability of distribution determine the supply of aquatic food to people. Aquatic food security is achieved when a food supply is sufficient, safe, sustainable, shockproof and sound: sufficient, to meet needs and preferences of people; safe, to provide nutritional benefit while posing minimal health risks; sustainable, to provide food now and for future generations; shock‐proof, to provide resilience to shocks in production systems and supply chains; and sound, to meet legal and ethical standards for welfare of animals, people and environment. Here, we present an integrated assessment of these elements of the aquatic food system in the United Kingdom, a system linked to dynamic global networks of producers, processors and markets. Our assessment addresses sufficiency of supply from aquaculture, fisheries and trade; safety of supply given biological, chemical and radiation hazards; social, economic and environmental sustainability of production systems and supply chains; system resilience to social, economic and environmental shocks; welfare of fish, people and environment; and the authenticity of food. Conventionally, these aspects of the food system are not assessed collectively, so information supporting our assessment is widely dispersed. Our assessment reveals trade‐offs and challenges in the food system that are easily overlooked in sectoral analyses of fisheries, aquaculture, health, medicine, human and fish welfare, safety and environment. We highlight potential benefits of an integrated, systematic and ongoing process to assess security of the aquatic food system and to predict impacts of social, economic and environmental change on food supply and demand. 相似文献
13.
Food ingestion,consumption and selectivity of pompano,Trachinotus ovatus (Linnaeus 1758) under different rotifer densities 下载免费PDF全文
下载免费PDF全文 Zhenhua Ma Huayang Guo Dianchang Zhang Chaoqun Hu Shigui Jiang 《Aquaculture Research》2015,46(11):2593-2603
The growth, survival, food selection and consumption of pompano larvae under different rotifer densities as well as their colour preference during the rotifer feeding stage were examined in this study. Growth and survival of fish larvae were not significantly affected when rotifer density was between 10 and 20 mL?1. Fish larvae grew slower at 1 and 40 rotifers mL?1 than at 10 and 20 rotifers mL?1, and higher fish survival was achieved when fish larvae were exposed to 10 and 20 rotifers mL?1. The rotifer density of 1 mL?1 not only reduced food ingestion during the early stage, but also delayed diet switch from rotifer to copepod nauplii. On 5 days post hatching (DPH), larval pompano ingested more rotifers in dark‐coloured tanks and ingested more rotifers when prey colour was green. Based on the results obtained in the present study, the culture of larval pompano larvae is recommended using dark wall tanks with a feeding density of 10–20 rotifers mL?1 during the initial feeding stage. This study proposes a management protocol to use appropriate type and quantity of live food to feed pompano larvae in a hatchery rearing condition, which could be applicable to the culture of fish larvae in other marine fish species. 相似文献
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对发展中国家微观层面的粮食获取能力及其影响因素的分析后认为,就发展中国家整体而言,由人们的自行生产能力、市场交易能力以及获取粮食援助的能力三方面构成的微观层面的粮食获取能力还较弱,粮食获取能力较弱的根本原因在于发展中国家的生产力落后和人均收入水平低。 相似文献
15.
Frozen mysids as an alternative to live Artemia in culturing seahorses Hippocampus abdominalis 总被引：1，自引：1，他引：1
This investigation examined the effects on growth and survival of seahorses Hippocampus abdominalis Leeson 1827 fed a 25% body weight (wet weight) daily ration of live Artemia sp. enriched with Algamac‐3050, frozen mysids Amblyops kempi or a combination of live enriched Artemia and frozen mysids. After 3 months there was no difference in seahorse length, wet weight, condition factor (CF), or food conversion ratios (FCR) between the treatments. Mean daily specific growth rate (SGR) was higher for the Artemia‐only treatment than for the mysid‐only treatment (P<0.05). FCRs ranged from 6.14 g to 8.72 g dry weight of food required to give a 1‐g dry weight increase in seahorses. There was no difference in survival between treatments. Fatty acid analysis revealed that mysids had a higher percentage composition of EPA, 20 : 5n‐3, and DHA, 22 : 6n‐3, but a lower composition of AA, 20 : 4n‐6, than enriched Artemia. Percentage n‐3 highly unsaturated fatty acids (HUFAs) in mysid levels were approximately twice that of Artemia. Proximate analysis revealed mysids to be higher than the enriched Artemia in protein and fats, and lower in water content. This experiment demonstrates that, although no growth advantage was derived from the use of frozen mysids, they can be used successfully as an alternative food to live enriched Artemia for H. abdominalis. The use of frozen mysids is highly recommended in commercial seahorse culture if the seahorses are to be sold into the live aquarium trade, as this may increase their chances of survival after sale. 相似文献
16.
为了解克氏原螯虾(Procambarus clarkii)对饲料感知的最大空间距离,在稻田养殖环境条件下,利用特定设计的试验设施,研究其对配合饲料的感知能力,以期为合理确定养殖水体投饵点数量和空间布局、增加饲料利用率提供科学依据。结果显示,克氏原螯虾对配合饲料感知的最大间隔距离估算为12 m;在食物间隔距离3 m和6 m捕获的雌虾与雄虾数量无显著性差异(χ2>1.19,df=1,P>0.270),表明雌性与雄性对配合饲料的感知能力没有显著差异。食物感知-搜索时间与食物间隔距离呈正相关,在食物间隔距离为3 m、6 m、9 m、12 m时,食物感知-搜索的最短时间分别为(1.8±0.5) min、(5.0±1.1) min、(11.4±1.7) min、(25.2±2.4) min,最长时间分别为(3.4±0.9) h、(7.3±0.6) h、(9.0±0.8) h、(10.0±1.3) h。当食物间隔距离为3 m和12 m时,受到配合饲料刺激后分别有(68.3±1.6)%和(36.3±1.9)%的克氏原螯虾能在3 h内到达食物源。研究表明,克氏原螯虾对配... 相似文献
17.
Feeding behavior and food consumption of Japanese whelk, <Emphasis Type="Italic">Buccinum isaotakii</Emphasis> (Neogastropoda: Buccinidae) 总被引：1，自引：0，他引：1
Abilities of detection and preference of food by a Japanese whelk, Buccinum isaotakii, were investigated under laboratory conditions. Consumption per food item and the corresponding assimilation efficiency were
also de termined. Whelks were more sensitive to fresh foods than boiled foods, detecting them in a short period of time varying
between 3.8 (±0.8) and 23.1 (±3.1) minutes. B. isaotakii preferred fish, polychate and bivalves and the time spent on these foods was more than 10 min as compared with those of shrimp
(2.0 min) and squid (1.0 min). The highest daily consumption rate was observed on sardine, followed by scallop, polychaete
and oyster. The relationship between shell length and consumption of different food items was positive. The coefficients of
determination were relatively high for sardine, scallop, polychaete and oyster (r
2, between 0.46 and 0.51) but not for clam, mussel shrimp and squid (r
2, between 0.003 and 0.176), suggesting that the former could be predators of consumption for B. isaotakii. Observed were relatively high assimilation efficiencies on sardine, scallop, polychaete, and oyster, ranging from 30 to
70%. The present results are the intial information pertaining to the feeding biology of this whelk, thus, in-depth studies
like an energy budget are recommended to deepen the understanding about seed production and resource management. 相似文献
18.
Fisheries or aquaculture? Unravelling key determinants of livelihoods in the Brazilian semi‐arid region 下载免费PDF全文
下载免费PDF全文 Priscila F M Lopes Adriana R Carvalho Sebastián Villasante Gustavo Gonzaga Henry‐Silva 《Aquaculture Research》2018,49(1):232-242
In impoverished semi‐arid regions in the world, reservoirs serve multiple purposes, including food provision through fisheries and aquaculture. Yet, the socio‐economic benefits of promoting both activities remain unclear. We independently assessed the socio‐economic benefits generated from fisheries and aquaculture, in two reservoirs in the Brazilian semi‐arid region (June 2013 to June 2014). These reservoirs produced 27.75 ton of farmed tilapia over a year (USD Purchasing Power Parities [PPP] 88,778.73) and provided at least 16.5 ton of fish through fisheries (USD PPP 37,557.81), based on data from four farmer associations. Our input–output model revealed that the local economy depends on both activities, which, therefore, contribute similarly to providing goods and services to different branches. Aquaculture generated much higher revenues (seven times) than fisheries, but also much higher losses (the most successful farm yielded an average income of USD PPP 592.41 monthly). Still, there were no statistical differences in income among the compared associations. Fisheries provided very but guaranteed income (USD PPP 311.02 ± 82.94) and employed over three times as many people and contributed much more (>3 times) to food security than aquaculture. Encouraging aquaculture through specific policies while overlooking fisheries is not advisable because poor fishers would not be able to deal with unpredictable outcomes and it would put their food security at risk. However, if initial external support is provided to fishers in order to buffer large losses, aquaculture could represent a way out of poverty by generating an opportunity for larger gains, as long as potential negative ecological impacts of aquaculture are accounted for. 相似文献
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根据东海区(26°00'~35°00'N、120°00'~126°30'E)大面调查渔获物的凤鲚(Coilia mystus)样本,对东、黄海凤鲚的食物组成、食性类型及其季节变化进行了定量分析。研究结果表明:(1)凤鲚饵料生物组成共计有10个类群,40种可鉴别饵料(包括未鉴定到种的种类),6种不可辨认类型饵料。依据相对重要性指数指标计算结果分析,桡足类(Copepoda)为最重要的饵料类群,IRI达到1 869,%IRI占56%,糠虾类(Mysidacea)、磷虾类(Euphausiacea)为次重要类群。(2)凤鲚摄食的浮游动物饵料出现频率达93.66%,底栖动物和游泳动物出现频率分别为0.66%、5.68%,属于浮游动物食性。(3)凤鲚的食物组成、摄食强度、食物生态位宽度均存在季节变化,春、夏、秋、冬四季摄食的饵料种类依次为35种、29种、10种和9种,春季主要摄食桡足类、鱼类和糠虾类,夏季主要摄食糠虾类和桡足类,秋季主要摄食桡足类和磷虾类,而冬季则主要摄食磷虾类和桡足类,各季中优势的单一类群%IRI均超过85%。凤鲚摄食等级较低,摄食等级3级以下四季都在70%以上,空胃率较高,秋季空胃率高达59.7%,平均胃饱满系数春季最高,冬季最低。春季相对其它季节摄食等级较高、空胃率最低、平均胃饱满系数最高,摄食强度明显高于其它季节。春、夏季节的食物多样性指数高于秋、冬季节。 相似文献
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为了解摄食行为对中华绒螯蟹(Eriocheir sinensis)的个体生长发育以及群体生活的影响,选取12只附肢健全的雄蟹,使用高清摄像头连续6 d记录其在1 h内的摄食行为。结果显示:每天摄食的河蟹比例约50%,第2天的摄食量显著高于另外5 d,第1天摄食反应时间显著高于另外5 d;河蟹摄食连续天数以连续摄食2 d的河蟹数量最多,各连续天数间蟹的摄食量无明显差异,连续摄食6 d的河蟹对饵料反应时间显著高于连续摄食3、4和5 d。河蟹摄食期间使用右螯、左螯和双螯的频率分别为55%、41%和4%。右螯比左螯长的河蟹比例为91.67%。螯长与摄食量无明显相关性,但螯长与体长存在正相关性(R^2=0.968 3,P<0.01)。结论:每天摄食的河蟹比例约占一半,平均摄食量约占体重的1.6%;摄食反应时间第1天最高,连续摄食可造成蟹对饵料的反应时间升高。雄性河蟹右螯较长,是摄食期间最常使用的螯肢。 相似文献