Dietary magnesium requirement and physiological responses of marine shrimp Litopenaeus vannamei reared in low salinity water   总被引：1，自引：0，他引：1  

K.-M. CHENG  C.-Q. HU  Y.-N. LIU  S.-X. ZHENG  & X.-J. QI 《Aquaculture Nutrition》2005,11(5):385-393

An 8‐week feeding experiment was conducted to determine the dietary magnesium (Mg) requirement and physiological responses of Litopenaeus vannamei in low salinity water of 2 g L^?1. Casein–gelatin‐based diets supplemented with seven levels of Mg (0, 0.4, 0.8, 1.6, 3.2, 6.4 and 8.0 g kg^?1) were fed to juvenile shrimp. Prior to the experiment, the postlarvae were gradually acclimated to the low salinity media and fed with a basal diet (0.5 g Mg kg^?1) for 2 weeks. After 8 weeks of feeding, survival ranged from 80.11% to 85.65% with no significant difference among the treatments. Hepatopancreas Mg²⁺‐ATPase and Na⁺/K⁺‐ATPase activities and muscle content of lipid and protein were not significantly affected by graded levels of Mg. The weight gain and mineral (calcium, potassium, sodium and total phosphorus) content of different tissues were significantly affected by dietary Mg levels, while there were no significant differences in ash and zinc content in tissues. The Mg content in tissues except hepatopancreas was maintained relatively constant regardless of dietary treatments. The dietary Mg requirement for optimal growth was 2.60–3.46 g Mg kg^?1 by using the polynomial regression analysis based on growth.  相似文献   

Characterization of intake and effluent waters from intensive and semi-intensive shrimp farms in Texas   总被引：2，自引：0，他引：2  

Tzachi M Samocha  I M Lopez  E R Jones  S Jackson  & A L Lawrence 《Aquaculture Research》2004,35(4):321-339

Two commercial shrimp farms in south Texas were evaluated for influent and effluent water quality from June to October 1994. The intensive farm, Taiwan Shrimp Village Association (TSV) had an average annual yield of 4630 kg ha^?1 while the semi‐intensive farm, Harlingen Shrimp Farm (HSF), had a yield of 1777 kg ha^?1. The study had three objectives: (1) to compare influent and effluent water from the intensive and semi‐intensive shrimp farms, (2) to show which effluent water‐quality indicators exceeded allowable limits, (3) to indicate inherent problems in farms operated with water exchange and summarize how findings from this study led to changes in farms' management that limited potential negative impact on receiving streams. Water samples were collected and analysed twice a week for the TSV farm and once a week for the HSF farm. Samples were analysed for dissolved oxygen (DO), salinity, pH, ammonia‐nitrogen (NH₃‐N), nitrite‐nitrogen (NO₂‐N), nitrate‐nitrogen (NO₃‐N), total phosphorus (TP), total reactive phosphorus (TRP), five‐day carbonaceous biochemical oxygen demand (cBOD₅), total suspended solids (TSS) and settleable solids (SettSols). Most of the effluent constituents showed fluctuations throughout the sampling period often related to harvest activity. Effluent pH at TSV was lower than influent values but within the regulatory requirements set by Texas Commission of Environmental Quality (TCEQ), formerly known as Texas Natural Resource Conservation Commission (TNRCC). HSF effluent pH values were higher than its influent, but still within TCEQ limits. Effluent DO mean levels were generally below the regulatory daily mean requirement, with values at TSV often below those for influent. Effluent nutrient concentrations and net loads were generally higher at the intensive shrimp farm, with NH₃‐N mean concentrations above the daily mean set by the TCEQ on several occasions. Effluent TSS concentrations were higher than influent for both farms, with daily mean values above the TCEQ limit. The two farms presented similar TSS concentrations despite their different stocking densities. However, TSS total net load and net load per hectare were higher at the intensive farm. The semi‐intensive farm presented higher cBOD₅ concentrations and net loads despite its lower stocking density, with daily mean values above the TCEQ limit. The cBOD₅ net load at TSV presented negative values indicating higher load at the influent than at the effluent. Analyses showed no evidence of self‐pollution between influent and effluent at the two farms. The high feed conversion ratio (FCR) values (2.3 and 2.7 for the intensive and the semi‐intensive farm respectively) suggest that better feed management is needed to reduce nutrient and solid net loads release from the two farms. The data obtained from this study resulted in several modifications in design and management of the two farms that reduced the potential negative impact on receiving streams. A brief summary of the improvement in selected effluent water‐quality indicators at the intensive shrimp farm is provided.  相似文献   

应用RT-PCR方法从进境南美白对虾亲虾中检出桃拉综合征病毒(Taura syndrome virus)   总被引：5，自引：0，他引：5  

陈信忠  龚艳清  孔繁德  王景明  周斌华  郑征  黄元成 《中国动物检疫》2003,20(12):21-22

应用PCR和RT—PCR技术，对一批进境的南美白对虾亲虾进行了多种病毒性病原的检疫。结果检出桃拉综合征病毒。临床观察也表明，该批亲虾体表散布大量黑色病灶，为TSV感染引起的TS典型病变。  相似文献   

Effect of culture system on the nutrition and growth performance of Pacific white shrimp Litopenaeus vannamei (Boone) fed different diets   总被引：2，自引：0，他引：2  

A.G.J. TACON  J.J. CODY  L.D. CONQUEST  S. DIVAKARAN  I.P. FORSTER  & O.E. DECAMP 《Aquaculture Nutrition》2002,8(2):121-137

Two 8-week feeding trials were conducted with juvenile Pacific white shrimp, Litopenaeus vannamei (Boone) to compare the growth and performance of animals fed a series of experimental and commercial pelleted shrimp and fish feeds and dietary feeding regimes within an indoor running-water culture system and an outdoor zero-water-exchange culture system. The best overall shrimp growth performance was observed for animals fed the experimental shrimp diet and all-day feeding regime under outdoor zero-water-exchange culture conditions. Final body weight and average weekly growth rate under these conditions were 2.8 and 3.4 times greater, respectively, than animals of similar size fed with the same diet under indoor running-water culture conditions. Although direct comparison between indoor and outdoor culture systems is difficult because of the lower indoor water temperatures, and consequently lower mean daily feed intake of animals, it is believed that the higher growth and feed performance of animals reared under outdoor `green-water' culture conditions was primarily due to their ability to obtain additional nutrients from food organisms endogenously produced within the zero-water-exchange culture system. The most promising features of zero-water-exchange culture systems are that they offer increased biosecurity, reduced feed costs and water use for the farmer, and by doing so provide a potential avenue of moving the shrimp culture industry along a path of greater sustainability and environmental compatibility.  相似文献   

凡纳滨对虾微卫星DNA的筛选及其特性的研究   总被引：1，自引：0，他引：1  

贾智英  全迎春  梁利群  孙效文 《上海海洋大学学报》2007,(1):11-15

采用小片段克隆法构建凡纳滨对虾的部分基因文库，用放射性同位素[y-^12P]ATP标记的（CA）15（AT）12（AG）12、（AAT）8、（AAG）8做探针筛选阳性克隆。共获得微卫星序列152个，其中二核苷酸为核心的微卫星序列：（AG）a〉（AC）a〉（AT）a，三核苷酸为核心的微卫星序列：（AAT）a〉（CAT）a〉（AAG）a应用引物设计软件primer3．0设计引物105对。选择合成10对理论上易出现影子带的引物，筛选后用31个凡纳滨对虾个体对这些引物进行了评估，结果10对引物中有8对引物能扩增出谱带，其中1对扩增产物出现影子带，1对扩增产物为单态．有6对扩增产物出现多态。  相似文献   

密度对凡纳滨对虾存活、生长和能量收支的影响     

王兴强  曹梅  马甡  董双林  阎斌伦 《勤云标准版测试》2005,(8)

研究了密度(12.04、24.08、48.16、144.49、240.81、337.13、433.46、529.78、626.11尾/m2)对凡纳滨对虾(平均初始湿重0.026±0.006g)存活、生长和能量收支的影响。实验周期45d。结果表明:I.12.04、24.08和48.16尾/m2密度水平对虾的存活率显著高于626.11尾/m2密度水平,但与其它处理差异不显著;II.12.04和24.08尾/m2密度水平对虾的特定生长率显著高于其它处理,特定生长率(SGRd)与密度(D)的回归方程为:SGRd=-0.3911Ln(D) 10.068(R2=0.8745)。  相似文献   

在不同盐度下氯氰菊酯对凡纳滨对虾的急性毒性效应研究     

邱勇  严峰  曾嶒  熊泽泉 《安徽农业科学》2012,40(32):15704-15705

[目的]为不同盐度下氯氰菊酯的使用和调控提供科学依据。[方法]采用静水生物法,研究了不同盐度下氯氰菊酯对凡纳滨对虾的急性毒性效应。[结果]在盐度20和5下氯氰菊酯对凡纳滨对虾的24、48、72、96 h半致死浓度(LC50)分别为0.767、0.440、0.383、0.038 2μg/L和0.437、0.313、0.203、0.170μg/L。在中、低盐度下氯氰菊酯对凡纳滨对虾的安全浓度(SC)分别为0.038 2和0.017 0μg/L。[结论]极低浓度的氯氰菊酯农药残留就可能会威胁凡纳滨对虾的养殖安全,应尽可能减少在虾塘及附近使用氯氰菊酯。  相似文献   

Excess dietary cholesterol may have an adverse effect on growth performance of early post-larval Litopenaeus vannamei     

J Niu  PF Chen  LX Tian  YJ Liu  HZ Lin  HJ Yang  GY Liang 《畜牧与生物技术杂志(英文版)》2012,3(1):19-5

One experiment was conducted to determine the nutritive value of cholesterol for post-larval shrimp, Litopenaeus vannamei. Four isoenergetic and isonitrogenous diets supplemented with four levels of cholesterol (D1, D2, D3 and D4 with 0, 0.5%, 1% and 2% cholesterol, respectively) were fed to triplicate groups of L. vannamei shrimp (mean initial wet weight 0.8 mg) for 27 days. After the trial, shrimp fed the D1 diet had the best growth performance (final body weights: FBW; weight gain: WG; specific growth rate: SGR), while there was no significant difference between diet treatments with respect to survival. The whole body crude protein level in the shrimp decreased with the increase in dietary cholesterol levels, while the whole body crude lipid level in shrimps in the D4 diet treatment was significantly higher (P < 0.05) than in other diet treatments. Dietary analysis indicated that the D1 diet contained 0.92% cholesterol prior to supplementation, which may have satisfied the dietary cholesterol requirement of post-larval L. vannamei; excess dietary cholesterol may thus lead to adverse effects on the growth performance of post-larval shrimp.  相似文献   

丁酸钠植物精油复合制剂对南美白对虾生长性能、致病性弧菌和非特异性免疫的影响     

钱希逸  李慧  徐亚飞  杨彩梅 《水产养殖》2022,(1):14-20

研究丁酸钠植物精油复合制剂对南美白对虾(Litopenaeus vannamei)生长性能、肠道微生物及非特异性免疫的影响.试验分为2组,对照组饲喂基础日粮,试验组饲喂基础日粮+2.5 kg/t 丁酸钠植物精油复合制剂.结果显示,相比对照组,试验组南美白对虾增长率提高11.73％(P＜0.01),质量增加率提高13.5...  相似文献   

用酶联免疫法测定虾蟹中残留的氯霉素   总被引：1，自引：0，他引：1  

黄冬梅  蔡友琼  毕士川  沈晓盛 《大连水产学院学报》2005,20(4):349-351

采用酶联免疫法测定了南美白对虾Penaeus vannamei和中华绒螯蟹Eriocheir sinensis中残留的氯霉素。比较了用不同方法处理样品对检测结果的影响,通过对检测范围、精密度、回收率等项目的测定,验证了该方法的可靠性。结果表明：氯霉素标准液为50～4050ng／L时,具有良好的线性关系;板问变异系数小于16．4％,样品测定的变异系数为9．4％～13．8％;用乙腈水溶液方法提取的回收率（84％～116％）比用乙酸乙酯提取的回收率（62％～92％）高。  相似文献