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1.
日本沼虾表皮蛋白-5基因全长cDNA克隆及表达分析   总被引:1,自引:0,他引:1  
为探究甲壳动物表皮蛋白多样性及其功能,根据表皮转录组资料,利用RACE技术扩增得到日本沼虾表皮蛋白-5基因的cDNA全长序列,分析其生物信息学、不同蜕皮时期的表达特征以及KK-42对其表达特征的影响。日本沼虾表皮蛋白-5基因的cDNA全长796bp,开放阅读框477bp,编码158个氨基酸,含RR基序,预测蛋白等电点为4.22,分子量为16.46ku;氨基酸序列比对发现日本沼虾表皮蛋白-5与克氏原螯虾Casp-2相似性最高,为76%,与其他甲壳动物表皮蛋白相似性为41%~53%。实时荧光定量PCR结果显示,日本沼虾表皮蛋白-5基因在3个时期——蜕皮间期、蜕皮前早期和蜕皮前晚期均有表达,其中在脱皮前晚期的相对表达量最高,为蜕皮间期的1400倍,与之有极显著差异(P0.01)。KK-42处理显著上调日本沼虾表皮蛋白-5基因在蜕皮前早期的表达,在处理后3、6h和48h表达量分别是对照组的6.3、4.8和11.4倍。KK-42诱导日本沼虾表皮蛋白-5基因的表达,使峰值前移,这可能是KK-42缩短日本沼虾幼虾蜕皮周期的机制之一。  相似文献   

2.
ABSTRACT

The freshwater prawn, Macrobrachium rosenbergii, commonly called ‘scampi,’ is the most important culturable freshwater species of prawn with a fairly high growth rate, wide range of temperature (15-35°C) and salinity tolerance. The nutrients required by this species for growth and associated physiological functions are similar to those required by other crustaceans. Current data suggest that a digestible protein level of above 30 is required for maximum growth and protein efficiency. Ingredients such as mussel meat meal, squid meal, and shrimp meal serve as potential sources of protein in formulated diets. The complete quantitative requirements for all the essential amino acids for this prawn species have not yet been worked out. With respect to non-protein energy supply in the form of carbohydrate, studies indicated that scampi is capable of utilizing various carbohydrate sources efficiently. Dietary carbohydrate in the form of complex polysaccharides appears to be more effective as an energy source. Like other crustaceans, scampi also has limited ability to synthesize sterol from acetate and mevalonic acid. Quantitative estimates of the essential fatty acid requirements have been made in post-larval scampi. Data on vitamin and mineral requirements are scarce. Recent developments in diet formulation, practical feeding practices and the aquaculture potential in India have been indicated with emphasis on sustainable production.  相似文献   

3.
池塘青虾高产养殖技术   总被引:1,自引:0,他引:1  
青虾,学名日本沼虾,肉质细嫩,味道鲜美,是近年来出现的新的养殖品种。因其养殖设施简单、投资少、效益高、市场容量大等特点,近年来池塘青虾养殖面积在杭嘉湖地区得到大规模的发展。目前全省养殖面积已达8万多亩,养殖技术日趋完善,养殖产量和养成规格不断提高,所取得的经济效益也十分明显。一般亩产青虾75—100kg,亩利润1500—2500元,高的亩产量可达150kg以上,亩利润高达4000多元。现将在池塘青虾养殖过程中所采取的主要技术措施总结如下。1虾塘条件1.1面积 1—4亩较适宜,太小易缺氧,太大管理…  相似文献   

4.
不同温度下2种沼虾磷酸酶活性变化的研究   总被引:1,自引:0,他引:1  
苏翔  汪桂玲  李家乐 《水产科学》2011,30(3):168-170
用比色法测量4℃和-70℃下离体的罗氏沼虾和日本沼虾肝胰腺中的碱性磷酸酶、酸性磷酸酶酶活性在一周内的变化。试验结果表明,4℃条件下保存的日本沼虾与罗氏沼虾的离体组织中碱性磷酸酶和酸性磷酸酶酶活性有效测定下时间为3 d,-70℃下有效测定时间为2 d,对后续酶活性试验没有大的影响。  相似文献   

5.
长江、高邮湖、太湖日本沼虾遗传多样性的RAPD分析   总被引:3,自引:0,他引:3  
采用随机扩增多态性DNA (RAPD)技术对取自长江、高邮湖、太湖3个野生群体的日本沼虾共51个个体的遗传多样性进行分析.10个随机引物共检测出54个位点(200-2500bp),长江、高邮湖、太湖各群体的多态位点比例分别为72.22%、53.70%、62.96%,基因多样性指数分别为0.2878、0.2380、0.2635.群体遗传多样性的Shannon信息指数分析表明,日本沼虾3个野生群体种质资源状况良好,遗传多样性水平较高.  相似文献   

6.
复方中草药对青虾免疫功能的影响   总被引:3,自引:0,他引:3  
将大黄、黄芩、党参、板蓝根等十余味中草药粉碎过筛后制成复方添加剂按1%、2%、3%的比例添加于基础饲料中制成颗粒药饵投喂青虾,测定青虾相关免疫指标的变化。结果表明,青虾血细胞吞噬百分比和吞噬指数、血清溶菌酶活力均显著提高。经嗜水气单胞菌攻毒后,各试验组的免疫保护率也明显提高。在各试验组中以2%的添加量的效果最好。试验证明,该添加剂可显著地提高青虾的免疫功能,能有效地预防嗜水气单胞菌的感染。  相似文献   

7.
采用组织切片及类固醇激素含量测定等方法,研究青虾Macrobrachium nipponense幼虾发育第1~31d的精巢、卵巢及促雄腺发育的起始时间、发育过程及成熟时间。结果表明:青虾幼虾发育到第10d(PL10)时促雄腺呈索状结构开始发育,随后经历增殖期(PL10)、合成期(PL13)和分泌期(PL19)3个发育阶段发育成熟,形成完整的促雄腺。青虾精巢和卵巢均在幼虾发育第13d(PL13)开始发育,精巢形成不规则排列的精原细胞,而卵巢生殖上皮开始分化为椭圆或多边形的卵原细胞。精巢经精原细胞期(PL13)、精母细胞期(PL16)、精细胞期(PL19)和精子期(PL22)4个发育阶段成熟,此时成熟的精巢生精小管内充满成熟的精子。卵巢经卵原细胞期(PL13)、初级卵母细胞期(PL16)、次级卵母细胞期(PL16)和卵子期(PL19)4个时期发育成熟,此时卵巢充满成熟卵子。从PL1到PL22,睾酮分泌量逐渐增加,维持在稳定水平至PL25后逐渐下降;从PL1到PL19,17β-雌二醇的分泌量逐渐增加,维持在稳定水平至PL25后逐渐下降。本研究显示:促雄腺与精巢发育过程均持续10d,但促雄腺早于精巢3d开始发育和成熟,这可为性别和生殖相关基因的筛选及性别调控机制的研究提供参考。  相似文献   

8.
Effects of harvesting methods (cull and batch) on population structure, growth, and yield of freshwater prawn, Macrobrachiurn rosenbergii, cultured at two densities (5/m2 and 10/m2) were evaluated. Females (67.4%) were more abundant than males (32.6%), but there was no effect of harvesting methods and stocking rates on sex ratio (P > 0.05). Mean survival rates ranged from 78.3 to 92.6%, being highest at a stocking density of 10/m2 and cull-harvested (P < 0.05), but were not different (P > 0.05) among three other treatments. After 196 days of culture, mean weights ranged from 25.3 to 29.9 g and were not significantly different from each other (P > 0.05). Mean weight of males was not hi her than that of f females (P > 0.05), except in one treatment (5/m2 , batch harvest) where males were heavier (P < 0.05). Maximum specific growth rate (SGR) was recorded for prawns cultured at a density of 5/m2 and cull-harvested (0.66%/day), followed by prawns at 10/m2 and cull-harvested (0.58%/day). Minimum SGR was found for prawns cultured at 10/m2 density and balch-harvested (0.43%/day). Maximum yield (2366 kg/ha and 2099 kg/ha) was recorded at the higher density (P < 0.05). Harvesting method had no effect on yield at any density (P > 0.05).  相似文献   

9.
Abstract.— Quantitative changes in the protein, lipid and carbohydrate were studied in the early larval stages of developing freshwater prawn Macrobrachium rosenbergii reared under fed and starved conditions to understand the relative importance of these nutrients in energy metabolism of the growing larvae. Larvae obtained from several females were stocked into three 250-L tanks at a density of 30 larvae/L. The feeding regime consisted of newly hatched Artemia nauplii. Protein was always the major organic constituent followed by lipids and then carbohydrates of both fed and starved larvae. Protein levels of both fed and starved larvae increased during development, suggesting an important role in morphogenesis. The decline of lipid during the larval growth that was more rapid for starved larvae, suggests a probable utilization of lipid as the major metabolic source of energy. Carbohydrates formed less than 5 and 2.4% of the larval dry weight of fed and starved larvae, respectively, suggesting their limited role in larval metabolism.  相似文献   

10.
利用微卫星DNA标记研究3种近亲交配形态型雄性罗氏沼虾遗传多样性,所用虾样均采自国家级(南宁)罗氏沼虾良种场,共150尾成年近亲交配的雄虾,其中蓝色长臂型、橙色长臂型、小个体型各50尾。研究结果表明,3组样品的生长发育差异显著,蓝色长臂型、橙色长臂型、小个体型各组中微卫星位点的总等位基因分别为24、28和22,3组样品所有位点的平均观察杂合度为0.474~0.556。其平均群体内近交系数为-0.0189,说明杂合子过剩,对比分析和群体间分化系数表明,3组雄虾遗传差异明显,最大遗传间距位于蓝色长臂型和小个体型,最小的遗传间距位于蓝色长臂型和橙色长臂型。研究结果将为罗氏沼虾优质父本选育和调控雄性遗传发育提供基础性遗传信息。  相似文献   

11.
选取450只平均抱卵量为960粒/尾健康活力强的抱卵虾作为亲本进行育苗试验,并对日本沼虾蚤状幼体分期进行系统观察。结果在孵化期间共获得蚤状幼体408 240尾,孵化率为94.5%,育苗后期共获得仔虾242 086尾,蚤状幼体发育到仔虾的成活率为59.3%,蚤状幼体可分为Ⅴ期。本试验结果为今后日本沼虾人工育苗技术推广提供参考。  相似文献   

12.
Abstract.— Amino acid profiles of freshwater prawn Macrobrachium rosenbergii were determined during early larval stages (I-IX) to provide some baseline biochemical information of the growing larvae. The larvae obtained from several females were stocked into three 250-L tanks at a density of 30 larvae/L. The feeding regime consisted of newly hatched Artemia nauplii and egg custard containing 5% cod liver oil. For each developmental stage, larval samples from each experimental tank were pooled, freeze dried and after acid hydrolysis, the quantification of amino acids was done by a reverse phase high performance liquid chromatography ( N = 2). The highest represented of the total amino acids were for glutamic acid and phenylalanine (with cystine) with ranges from 13.4–16.6 and 9.7–11.5%, respectively, whereas tryptophan (1.4–1.6%). methionine (1.4–2.7%) and histidine (2.9–4.2%) were relatively lower. The levels of the following essential amino acids did not significantly change during larval development: arginine, leucine, phenylalanine (plus cystine), threonine, tryptophan and valine. Despite statistically significant changes that were observed in levels of some amino acids, amino acid composition appeared to be relatively unchanged during the larval growth. The results may suggest that the amino acid requirements of the freshwater prawn is relatively constant during larval life and can be satistied by a suitable protein source that resembles the larval amino acid profile.  相似文献   

13.
Three genetic strains (Texas [cultured], Hawaii [cultured], and Myanmar [wild]) of freshwater prawn, Macrobrachium rosenbergii, were characterized and compared under two pond grow‐out management technologies using a 3 × 2 factorial design. Juvenile prawns (45 d nursed juveniles) from each strain were stocked at individual average weights of 0.4 ± 0.3 g (Texas), 0.3 ± 0.2 g (Hawaii), and 0.3 ± 0.2 g (Myanmar). The low input management technology prawns were stocked at 24,700 /ha with no added substrate. The high input management technology prawns were stocked at 74,100 /ha with the addition of artificial substrate. Each of the six treatment combinations were replicated in three, 0.04 ha earthen ponds (total of 18 ponds). Prawns were fed a sinking pellet (32% protein) once daily at a standardized rate. After 112 d, prawns were harvested, bulk weighed, and counted. Survival of Texas strain (95%) was significantly higher (P ≤ 0.05) than Myanmar strain (77–80%) under both management technologies with survival of Hawaii strain (86–91%) intermediate and not significantly different (P > 0.05) from other strains. Under both management technologies, average weight, total production, and marketable percentage (>20 g) was significantly better (P ≤ 0.05) in Texas and Hawaii strains in comparison to the Myanmar strain. These data appear to indicate that the cultured strains evaluated in this study demonstrate positive impacts of domestication and do not indicate inbreeding depression.  相似文献   

14.
吴江市地处太湖东侧水网地带 ,有众多的淡水水域 ,水产养殖业历来发达。为了提高传统养殖渔业的经济效益 ,从 1 992年起着重推行罗氏沼虾池塘养殖规模经营。由于池塘养虾投资少、见效快、收益大、生产稳定 ,近十年来 ,各乡、镇的养殖面积逐年扩大 ,生产技术也渐趋成熟。现将罗氏沼虾的池塘养成主要技术措施介绍如下 :一、池塘条件1 .水源  引用天然江河、湖泊等水源的水均可 ,但使用前必须了解 :水源是否被工业废水污染过 ;在罗氏沼虾生长高峰期 ,水的供应量是否有保证。2 .水温  罗氏沼虾原产热带、亚热带 ,对低温的适应能力差。其适宜…  相似文献   

15.
This paper deals with production systems, cost structure, and profitability of freshwater prawn, Macrobrachium rosenbergii, farming in a new area of Mymensingh district in the north‐central part of Bangladesh. In the study area, prawn farming practice is still extensive, and only a few farmers (20%) cultivate semiintensively. The costs and returns of extensive and semiintensive farming systems are compared. All farmers in different farming systems made a profit, with seed and feed dominating variable costs. Considerable variation in production costs and profitability was observed. Based on the Cobb–Douglas production function model, return to scale indicates that there is scope to increase production and income from prawn farms in extensive and semiintensive systems by applying more inputs (i.e., seed, feed, and fertilizer).  相似文献   

16.
2个青虾群体生长的比较研究   总被引:1,自引:0,他引:1  
王建华 《水产科学》2005,24(3):19-20
以太湖野生青虾和长兴养殖青虾为亲体繁殖的虾苗(分别记作了野生群和养殖群)进行生长对比试验,经90d饲养,野生群体长为46 70cm,养殖群为37 60cm;体重日绝对增重率野生群为4 638%,养殖群为3 839%;成活率野生群为(98 6±2 4)%,养殖群为(94 9±1 6)%;抱卵率野生群为(41 3±2 3)%,养殖群为(62 8±2 8)%。野生青虾繁殖的虾苗在体长、体重、成活率和性成熟等生长性能均优于养殖青虾繁殖的虾苗。  相似文献   

17.
ABSTRACT

Effects of three diets: (1) complete diet; (2) supplemental diet (vitamin and mineral supplements not added); and (3) the supplemental diet with an adjunct organic fertilization regimen (using distiller's dried grains with solubles [DDGS]) on benthic macroinvertebrate populations and water quality in experimental ponds used to culture freshwater prawns, Macrobrachium rosenbergii were investigated. Benthic samples were taken from deep (1.5 m) and shallow (1.0 m) areas of each of nine 0.02-ha ponds every three weeks, using a 0.09-m2 Ekman dredge. The abundance of gastro-pods, oligochaetes, total non-insects, chironomids, total dipterans, total insects, and total macroinvertebrates was significantly higher (P <0.05) in ponds receiving the complete diet, possibly due to lower predatory pressure by prawns or direct benefits of micronutri-ents. Total macroinvertebrate abundance was significantly decreased (P <0.05) in ponds receiving supplemental diet (with and without organic fertilization), possibly due to increased predation by prawns to supplement the nutrition not provided by the lower quality diet. Organic fertilization significantly increased (P <0.05) the abundance of oligochaetes and total macroinvertebrates. These data suggest that M. rosenbergii can adjust to reduced feed quality by increasing consumption of benthic fauna.  相似文献   

18.
有机硒对汞致日本沼虾毒性的拮抗作用   总被引:2,自引:0,他引:2  
研究了饲料中添加0.45 μg/g的富硒酵母对日本沼虾生长及对Hg2+毒性的拮抗作用,探明SOD作为Hg胁迫指标的可行性.选择体长2.6~3.0 cm、体质量0.30~0.40 g的日本沼虾,暂养于 60 cm×30 cm×45 cm的水族缸中,投喂含豆油、面粉、豆粉、玉米面、维生素预混物、无机盐预混物的配合饲料.结果表明,有机硒组的体长和体质量增长率均大于无硒对照组;有机硒组和无硒对照组中日本沼虾的SOD活力均随HgCl2质量浓度呈现峰值变化;说明饲料中添加适量有机硒可促进机体生长,提高机体SOD的活力,在一定程度上拮抗HgCl2所致的毒性.  相似文献   

19.
ABSTRACT

In temperate regions, post-larvae freshwater prawn, Macrobrachium rosenbergii, are grown to more advanced sizes in tanks prior to pond stocking. This intermediate stage of culture is referred to as the nursery period. Little research has been conducted on different management practices on juvenile prawn growth and survival during this 30-60 day period. Survival during the nursery stage has been highly variable and may be related to the cannibalistic behavior of juvenile freshwater prawn when cultured at high densities in the nursery. The objective of this study was to evaluate the effect of stocking density, relative to the provision of artificial substrate (number of prawns/m2 of substrate), on growth, survival, and economic variables for freshwater prawn juveniles during nursery production. Post-larvae (0.01%0.00 g, n = 300) were stocked into nine 1900 L tanks, each provided with 20.5 m2 of artificial substrate in the form of horizontal layers of black plastic mesh (10 mm) spaced 5 cm apart. Tanks were randomly assigned one of three prawn densities (215, 430, or 860 post-larvae/m2 of substrate), which equated to 2.3,4.6 and 9.2 prawn/L, respectively. Juvenile prawn were fed a commercial trout diet (42% protein) at a percentage of body weight according to a feed rate table. Water quality was maintained using a flow rate of 8 L/min in each tank from a reservoir pond. Temperature was maintained at approximately 28°C using heat pumps. After 56 days there was no significant difference (P >0.05) in average weight of juvenile prawn stocked at the three densities (0 = 0.58%0.12 g, n = 9). Survival was significantly lower (P <0.05) for prawn stocked at 860 m2 (62%) than in those stocked at 430/m2 (78%) and 215/m2 (94%), which were not statistically different (P >0.05). Even with reduced survival, the highest stocking density produced the greatest number of nursed juveniles based on both tank volume (5.5/l) and surface area (530/m2), at the lowest average cost.  相似文献   

20.
Chemical compositions and thermal properties of cultured freshwater prawn meat (FPM) were studied. FPM contained 83.2% protein (dry basis), 62.7% of which was myofibrillar protein. Pepsin-soluble collagen (PSC) and insoluble collagen (ISC) contents were 0.63 and 0.32%, respectively. Both collagens were similar to type V collagen from porcine placenta. Glutamic acid/glutamine, arginine, aspartic acid/?asparagine, and lysine were abundant amino acids in FPM. Glycine, proline, hydroxyproline, and aspartic acid/?asparagine were predominant in both collagens. FPM exhibited thermal transition temperatures (Tmax) of 48.3 and 64.7°C, whereas Tmax of PSC and ISC were 43.0 and 46.0°C, respectively. Textural changes in FPM during post-mortem storage on ice are plausibly dependent upon its compositional and thermal properties.  相似文献   

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