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中国东南沿海青蟹属(Scylla)的种类组成 总被引:15,自引:1,他引:14
为调查青蟹属在中国大陆东南沿海的种类组成及明确优势种的种类,采集了13个地区共413只青蟹。通过形态比较,确认有4个种,它们是:锯缘青蟹(Scylla serrata), 紫螯青蟹(Scylla tranquebarica), 拟穴青蟹(Scylla paramamosain),榄绿青蟹(Scylla olivacea)。这4个种类可以从头胸甲额缘4齿的长度(FMSH/DFMS)、形状,螯足腕节内刺的有无、螯足及步足斑纹来区分。其中拟穴青蟹在中国大陆东南沿海分布最广,数量最多,其他3个种仅在海南和北部湾被发现。在拟穴青蟹中有9.7%的成熟个体和33.3%未成熟个体具有螯足内刺,因此不能仅凭借这个特征来鉴别拟穴青蟹。本文对青蟹属4个种的特征进行了描述并编制分种检索表。图2表4参26 相似文献
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拟穴青蟹(Scylla paramamosain)隶属节肢动物门(Arthropoda)、甲壳纲(Crustacea)、十足目(Decapoda)、短尾亚目(Brachyura)、梭子蟹科(Portunidae)、青蟹属(Scylla),是我国传统珍贵海产品(林琪等,2007)。拟穴青蟹作为一种我国南方沿海主要的海水捕捞和养殖的对象,具有食谱广泛、生长繁殖快、适应性和抗病能力强等特点。全国养殖面积3余万hm2,年产量15.19×104 t (中国渔业统计年鉴,2018)。 相似文献
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白斑综合征病毒(WSSV)在拟穴青蟹体内增殖的研究 总被引:1,自引:0,他引:1
拟穴青蟹(Scylla paramamosain)因肉质鲜美、生长快速而成为我国主要的海水养殖经济蟹类,但是随着养殖规模的不断扩大,病害问题也越发严重。本研究通过流行病学调查和定量PCR跟踪检测的方法,研究了拟穴青蟹对白斑综合征病毒(WSSV)的易感性和WSSV在拟穴青蟹体内的增殖情况。结果表明,拟穴青蟹是WSSV的自然宿主,自然携带率为8.47%。WSSV可通过口服途径感染拟穴青蟹,并在拟穴青蟹体内快速增殖,注射感染5 d后,病毒量达到感染1d时的1.1×109倍,当病毒累积到一定量后即可致死拟穴青蟹。研究表明,拟穴青蟹是WSSV的天然宿主,在虾蟹混养过程中可以通过摄食WSSV感染虾而带毒或发病,并因此成为WSSV传播媒介,从而对虾蟹混养条件下WSSV的防治效果产生重要影响。 相似文献
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This is an initial paper in a series of overviews of biological research and aquaculture development of the mud crab, Scylla serrata, in China. Results of experimental ecological studies on mud crabs are reported here. As a result of these experimental studies, results that are important for mud crab culture were also discovered and these include, methods to condition and manage broodstock, determination of ecological conditions that are suitable for embryonic development, and the influence of temperature, salinity, diet and larval density on development and survival of larvae. Results of this work will be useful in establishing a good method for artificial mass culture of larvae. 相似文献
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Assessment of dietary lecithin and cholesterol requirements of mud crab, Scylla serrata, megalopa using semi-purified microbound diets 总被引:1,自引:0,他引:1
The effects of varying dietary lecithin and cholesterol levels on growth, development and survival of mud crab, Scylla serrata, megalopa were evaluated using six semi‐purified, microbound diets formulated to be iso‐energetic and containing three levels of supplemental lecithin (0, 20 and 40 g kg−1 diet dry weight) and two levels of supplemental cholesterol (0 and 7 g kg−1 diet dry weight). Fifteen megalopa were reared individually in each treatment and the nutritional value of diets was assessed on basis of mean dry weight and mean carapace width of newly settled first crab stage, as well as development time to the first crab stage and overall survival. A significant interaction between supplemental dietary lecithin and supplemental dietary cholesterol was found for final mean dry weight of newly settled crabs, and highest survival (60%) was recorded for megalopa fed diets containing the highest levels of dietary lecithin (39.7–44.1 g kg−1) (diet 5 and 6) regardless of whether diets were supplemented with cholesterol; this rate of survival was identical to that of megalopa fed live Artemia nauplii. The results indicate that supplemental dietary cholesterol may not be essential for mud crab megalopa when fed diets containing sufficient levels of supplemental dietary phospholipids. 相似文献
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通过对越冬和非越冬锯缘青蟹、脊尾白虾、弹涂鱼耐生石灰试验,证明青蟹有很强的耐生石灰能力,脊尾白虾有较强的耐生石灰能力。蟹虾围塘养殖在围塘清淤后对越冬青蟹进行生石灰消毒,养殖过程中定期用生石灰泼洒,并与对照塘做对比试验,以及大面积推广应用,结果表明:使用生石灰能使围塘锯缘青蟹、脊尾白虾发病率显著减少,成活率显著提高,生长明显加快,蜕壳时间相对集中,饵料系数明显降低,产量和效益显著提高。生石灰对围塘蟹虾健康生长有很大作用。 相似文献
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An experiment was conducted to evaluate the effect of different forms of Artemia biomass as a food source on survival, molting and growth rate of mud crab Scylla paramamosain. Instar 1 crablets with a mean weight of 0.0082 ± 0.0007 g were reared both individually and communally and fed with different diets consisting of fresh shrimp meat (control feed), live Artemia biomass, frozen Artemia biomass and a dried Artemia‐based formulated feed for 40 days. The highest survival was obtained for crablets receiving live Artemia (92.5% and 75.8%) followed by the groups fed with frozen biomass (90.0% and 47.5%), the control feed (72.5% and 24.2%) and the dried Artemia‐based diet (60.0% and 21.7%) for individual and communal cultures, respectively. The intermolt period, the total number of moltings and the growth rate, which were determined on individually reared crabs, showed the same pattern as for survival. The results suggest that crab performance decreased in the following order: live Artemia>frozen Artemia > fresh shrimp meat > dried Artemia‐based formulated feed. Live Artemia biomass proved an ideal feed for nursery of Scylla paramamosain crabs. Frozen Artemia biomass may be an alternative in times of shortage. Our findings illustrate the high potential for local utilization of Artemia biomass in Vietnam for reliable production of mud crab juveniles. 相似文献
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Effect of dietary cholesterol levels on growth performance,body composition and gene expression of juvenile mud crab Scylla paramamosain 下载免费PDF全文
Puqiang Zheng Jiteng Wang Tao Han Min Yang Xinyu Li Chunlin Wang 《Aquaculture Research》2018,49(10):3434-3441
A 56‐day feeding trial was conducted to investigate the effect of dietary cholesterol (CHOL) levels on growth performance, body composition and gene expression of juvenile mud crab (Scylla paramamosain). Four isonitrogenous and isoenergetic diets were formulated with 0.4%, 0.8%, 1.2% and 1.6% CHOL supplemented, and the final dietary CHOL concentrations were 0.72%, 1.11%, 1.49% and 1.83% respectively. Each dietary treatment was performed with three replicates (28 crabs per replicate, initial body weight 0.04 g). At the termination of the experiment, although the survival had no statistic difference in all treatments, the mud crabs fed the lowest CHOL diet had the lowest survival rate. The weight gain (WG) of mud crab significantly increased with dietary CHOL level up to 1.11% and then significantly decreased with dietary CHOL level further increased. The total‐cholesterol (T‐CHOL) content in whole body had an increasing trend with the dietary CHOL level increased. Besides, dietary CHOL supplement generally increased the hepatic superoxide dismutase (SOD) activity, and the mud crabs fed diets CHOL1.11 and CHOL1.49 showed significantly higher value than those fed other diets. The hepatic aspartate aminotransferase (AST) activity decreased slightly with dietary CHOL level up to 1.11% and then significantly increased with CHOL level further increased. The mRNA expression of ecdysone receptor (EcR) gene in the eyestalk obviously increased with dietary CHOL level up to 1.11% and then significantly decreased with dietary CHOL further increased. These results suggested that about 1.11% dietary CHOL seem fulfil to maintain good growth performance and healthy condition for juvenile S. paramamosain. 相似文献
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饲料蛋白质水平对拟穴青蟹幼蟹生长性能、体成分和消化酶活性的影响 总被引:2,自引:1,他引:1
用蛋白质水平分别为31.45%,36.37%,41.55%,46.13%,51.72%和56.86%的6种等能饲料,对初始体重为(11.86?0.11)mg的拟穴青蟹(Scylla paramamosain)幼蟹进行为期3周的养殖实验,考察饲料蛋白质水平对拟穴青蟹幼蟹生长性能、体成分以及消化酶活性的影响,以期获得拟穴青蟹幼蟹饲料蛋白质的适宜添加量。结果表明,饲料蛋白质水平对拟穴青蟹幼蟹的成活率影响不显著(P0.05);幼蟹的增重率和特定生长率随饲料蛋白质水平的提高先显著升高(P0.05)后稍有下降,最大值出现在蛋白质水平为51.72%的实验组;随着饲料蛋白质水平的提高,幼蟹粗蛋白质含量显著升高(P0.05)后趋于稳定,粗脂肪含量显著降低(P0.05),灰分含量先显著升高(P0.05)后显著降低(P0.05),水分含量则没有显著变化(P0.05);随着饲料蛋白质水平的提高,幼蟹蛋白酶活性显著升高(P0.05),淀粉酶活性显著降低(P0.05),各组脂肪酶活性也有显著差异(P0.05),但没有明显的变化规律。本研究条件下,饲料蛋白质水平在41.55%~56.86%,拟穴青蟹幼蟹均表现出较好的生长率,增重率和蛋白质水平的回归分析表明,幼蟹饲料蛋白质适宜水平为49.03%。 相似文献
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The effects of varying levels of dietary cholesterol on growth, development time and survival of mud crab, Scylla serrata megalopa were investigated using semi-purified microbound diets (MBD). Five iso-energetic diets containing different level of cholesterol ranging from 0.14% to 1% of dry weight of the diet were tested. Fifteen megalopa were reared individually for each dietary treatment, and development time and survival were recorded on a daily basis. More than 25% of megalopa from all treatments were able to metamorphose into the first crab stage, suggesting that the endogenous level of cholesterol in the basal diet (0.14%) was sufficient to support development of the megalopa stage of this species. Widest mean carapace width (3.53 ± 0.08 mm) and highest mean dry weight (2.11 ± 0.22 mg) were recorded for juveniles that molted from megalopa fed live Artemia, whereas no megalopa in the unfed control treatment metamorphosed into crabs. The average development time from megalopa to the juvenile crab stage varied between the treatments, where megalopa fed live Artemia or MBD containing 0.2%, 0.4% or 0.8% total cholesterol showed the most synchronized molting (between 8.0 and 9.9 days). Longest development time was recorded for the megalopa fed diets containing 0.14% or 1% total cholesterol (both 11 days). Highest survival (74.3%) was recorded for the megalopa fed a diet containing 0.8% cholesterol. The results of this study are valuable in research to develop formulated diets for mud crab larvae as a replacement for live food in hatchery culture. 相似文献
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我国蟹类土池育苗技术研究进展 总被引:1,自引:0,他引:1
蟹类养殖产业已成为我国水产养殖的支柱产业之一。中华绒螯蟹(Eriocheir sinensis,以下简称河蟹)、三疣梭子蟹(Portunus trituberculatus,以下简称梭子蟹)、拟穴青蟹(Scylla paramamosain,以下简称青蟹)是我国主要的养殖蟹类。目前3种蟹类土池育苗技术发展不平衡,河蟹、梭子蟹土池育苗技术较为成熟,已经普及推广并在养殖生产中发挥重要作用;青蟹土池育苗尚未有成功的报道。本文综述了我国河蟹、梭子蟹、青蟹苗种生产技术,尤其是土池育苗技术的研究进展,并对河蟹、梭子蟹土池育苗关键技术进行分析,旨在探讨蟹类土池育苗技术应用于青蟹土池育苗的可行性。 相似文献
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Stepwise function of natural growth for Scylla serrata in East Africa: a valuable tool for assessing growth of mud crabs in aquaculture 下载免费PDF全文
Per‐Olav Moksnes David Oersted Mirera Emma Björkvik Muumin Iddi Hamad Humphrey Matalu Mahudi Daniel Nyqvist Narriman Jiddawi Max Troell 《Aquaculture Research》2015,46(12):2938-2953
Predicting growth is critical in aquaculture, but models of growth are largely missing for mud crab species. Here, we present the first model of natural growth in juvenile and adult mud crabs Scylla serrata from East Africa using a stepwise growth function based on data on intermoult periods and growth at moult from field mark‐recapture, pond and laboratory studies. The results showed a sigmoid growth pattern in carapace width and suggest that S. serrata in East Africa will reach 300 g and sexual maturity ~9.9 months after settlement, and a commercial size of 500 g after 12.4 months. Analyses of the literature identified several issues with the common praxis to compare standard growth measures between aquaculture studies with different initial size or growing periods. Using the new growth function to estimate the proportional difference between modelled and obtained growth as an alternative method, we show that growth rates of S. serrata cultured in cage systems, which are dominant in East Africa, was <40% of the estimated natural growth and growth obtained in pond systems. The analysis also indicated that growth rates of S. serrata in Southeast Asia was over 50% higher compared with similar culture systems in East Africa, and that different species of mud crabs had large differences in growth rates. This study shows that growth in the present mud crab aquaculture systems in East Africa is below their expected potential. Further work is needed to identify the factors behind this observation. 相似文献