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对虾养殖实验围隔中的固氮作用及其氮输入 总被引:2,自引:0,他引:2
1997年6~10月,以乙炔还原法进行了不同放养模式下对虾养殖实验中生物固氮作用的测定。结果表明,各围隔中,对虾单养(Y-4)和对虾+海湾扇贝(Y-5)的固氮作用较高,均值分别为2.62μgN/(L·hr)和2.65μgN/(L·hr);对虾+罗非鱼+缢蛏(T-5)的最低,为1.53μgN/(L·hr),对虾+缢蛏(Y-6)和对虾+罗非鱼(Y-7)的分别为2.30μgN/(L·hr)和1.89μgN/(L·hr)。各围隔中固氮速率较高与水体有效氮含量较低及有效氮磷比值不高有关。水层固氮蓝藻主要为蓝球藻(Chrococus)和念珠藻(Nostoc)。估算各围隔实验期间固氮作用输入分别为Y-4∶17.72g;Y-5∶19.63g;Y-6∶9.05g;Y-7∶10.59g;T-5∶7.99g。 相似文献
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病免与不同剂型维生素C对中国对虾生长影响与防病治病试验 总被引:2,自引:0,他引:2
为探索促进中国对虾生长防病治病新途径,进行了多种剂型VC和病免的使用效果试验,结果:不同剂型VC喂养对虾均优于对照组,其中以VC硫酸酯钾效果最好,病免在虾病大暴发情况下有明显的抑制病害作用,并能提高对虾成活率和增重率。 相似文献
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L-肉碱对日本鳗鲡生长性能的影响 总被引:12,自引:0,他引:12
在日本鳗鲡的饲料中添加肉碱(含有50%的L-肉碱),对鳗体的增重有正面影响。与不添加肉碱的对照组相比,饲料中添加200×10-6和400×10-6的肉碱后,日本鳗鲡的绝对增重分别增加68%和28%;同时,饲料系数分别降低8%和10%;饲料中加入200×10-6的肉碱,鳗鲡的生长性能较加入400×10-6的更好。 相似文献
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中国对虾对Pb、Cr、Zn及其混合物的回避反应 总被引:3,自引:0,他引:3
利用“Y”形回避槽,进行了中国对虾( Penaeus chinensis) 对Pb 、Cr、Zn 及其混 合物的回避反应实验。计算得出中国对虾对Pb 、Cr、Zn 的50 % 回避率浓度分别为11 .4、33.2 、和238.1mg/L。对虾对Pb - Cr 及Pb - Zn 混合液的回避反应呈相加作用,但当混合液浓度为0.5 毒性单位Pb加0 .5 毒性单位Zn 时,回避反应呈协同作用。 相似文献
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用四种试验饵料,其中分别含有1%高纯度的ω-3及ω-6不饱和脂肪酸(亚油酸C18∶2ω6、亚麻酸C18∶3ω3、花生四烯酸C20∶4ω6、二十二碳六烯酸C22∶6ω,DHA)以及一种对照饵料含有5%棕榈酸C16∶0和油酸C18∶1ω9混合物对中国对虾(PenaeusorientalisKishinouye)幼虾进行了为期32天的投喂试验,从成活率、蜕皮次数及增重等实验结果可见二十二碳六烯酸(DHA)对中国对虾幼虾具有最高的营养价值。同时,对海捕和人工养殖的中国对虾的脂肪酸组成进行了比较,两者都含有大量的ω-3系列的高度不饱和脂肪酸;但是与海捕虾相比较,人工养殖对虾的DHA含量较低,而亚油酸含量较高。上列结果表明在对虾饵料中补充富含DHA的脂肪源将有效地促进对虾增产。 相似文献
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对虾池不同综合养殖系统效率和效益的比较研究 总被引:7,自引:0,他引:7
利用50个5.0×5.0×1.8m陆基围隔研究了中国对虾与台湾红罗非鱼、海湾扇贝和缢蛏投饵或施肥混养及鲈鱼与中国对虾和台湾红罗非鱼混养最佳结构的生态效率、生产效果和经济效益。结果表明,几种综合养殖系统最佳结构下各种养殖对象对N的绝对利用率由高至低依次为:鲈鱼-对虾-罗非鱼(30.91%)>对虾-海湾扇贝(21.09%)>对虾-罗非鱼施肥混养(20.12%)>对虾-罗非鱼投饵混养(17.81%)>对虾-缢蛏(16.93%)>单养对虾(11.52%);对P的绝对利用率由高至低依次为:对虾-缢蛏(16.08%)>鲈鱼-对虾-罗非鱼(12.83%)>对虾-罗非鱼投饵混养(12.63%)>单养对虾(10.88%)>对虾-海湾扇贝(6.01%)>对虾-罗非鱼施肥混养(4.04%);其产出投入比由高至低依次为:对虾-罗非鱼投饵混养(1.99)>对虾-罗非鱼施肥混养(1.98)>对虾-海湾扇贝(1.53)>单养对虾(1.38)>鲈鱼-对虾-罗非鱼(1.30)>对虾-缢蛏(1.23)。 相似文献
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在水温(18±0.5)℃下,利用生物化学方法测定施氏鲟Acipenserinae schrenkii胚胎发育过程中微量元素的含量,分析胚胎发育进程与微量元素含量的关系,为稚、幼鱼及亲鱼培育的营养需求量和饲料配制提供参考。结果显示:胚胎发育过程中,Fe、Mn、Cu、Zn含量的变化规律与代谢高峰期各不同。Fe含量呈先降低-升高的变化趋势,孵出期最高(18.12mg/kg);Mn含量先降低后升高,受精卵期含量最高(1.04mg/kg);Cu含量的高峰期分别为卵黄栓期、心搏期、孵化早期和孵出期,含量分别为1.66mg/kg、1.95mg/kg、1.83mg/kg和1.93mg/kg;卵裂期Zn含量最高(10.86mg/kg);视泡期微量元素的含量最低。 相似文献
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本文介绍了氨基酸微量元素螯合物的概念、特点以及作用机理,在此基础上探讨了其在反刍动物上的应用效果和使用时的注意事项。 相似文献
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星虫微量元素含量的测定 总被引:10,自引:0,他引:10
用原子吸收光谱法全面系统地对星虫肉中微量元素含量进行分析测定、评价星虫肉中的微量元素的含量。结果表明,样品中营养元素Mg、Ca、Fe、Zn、Se等含量丰富,而有害微量元素,如As、Pb、Cd等含量低。为星虫的经济价值、营养价值以及药用功能的进一研究和开发利用提供了重要依据。 相似文献
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人工模拟生态养殖子二代大鲵肌肉营养成分分析 总被引:6,自引:0,他引:6
利用生化手段, 对1龄人工模拟生态养殖子二代大鲵的肌肉营养成分进行了分析, 旨在评价大鲵的营养价值, 并为其配合饲料的研制提供基础资料和理论依据。结果表明, 大鲵肌肉(鲜样)中粗蛋白含量16. 93%, 粗脂肪含量2. 70%, 水分含量79. 00%, 粗灰分含量1. 14%。肌肉中含有18种氨基酸, 其中8种人体必需氨基酸总量为7. 34% , 占氨基酸总量的40. 46%; 4种鲜味氨基酸总量为7. 11%, 占氨基酸总量的39. 19%。微量元素比值合理。表明人工模拟生态养殖子二代大鲵有较高的营养价值。 相似文献
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根据2012年9月~10月于南海采集的鸢乌贼(Sthenoteuthis oualaniensis)样本,利用激光剥蚀电感等离子质谱法(laser ablation inductively coupled plasma mass spectrometry,LA-ICP-MS)分析鸢乌贼耳石微量元素组成及分布。结果显示,南海鸢乌贼耳石含量前10位的元素依次为钙(Ca)、锶(Sr)、钠(Na)、磷(P)、钾(K)、镁(Mg)、锌(Zn)、铝(Al)、铜(Cu)和镍(Ni)。P方差分析发现,鸢乌贼耳石微量元素Ca(P=0.017)、Sr(P=0.016)、Na(P=0.042)种群差异显著(P0.05);中型群Ca(P=0.026)、Sr(P=0.021)、Na(P=0.025)性别差异显著(P0.05),微型群性别差异不显著(P0.05);中型群Cu(P=0.002)、Ni(P=0.001)日龄差异显著(P0.05),微型群P(P=0.000)、Mg(P=0.002)、Zn(P=0.023)、Al(P=0.000)、Cu(P=0.003)日龄差异显著(P0.05)。南海鸢乌贼Sr含量随纬度的降低而减少,且0日龄高于10日龄。 相似文献
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Paul Chittaro Jens Hegg Abby Fuhrman Devin Robichaux Rothboury Doung Brian Beckman Chris Fisher Jeff Vervoort Brian Kennedy 《Ecology of Freshwater Fish》2023,32(1):107-119
Effective species management often requires understanding patterns of movement and habitat use. A common approach in identifying where individuals reside relies upon chemical tracers from the environment that are incorporated into an individual's tissues. For fish, isotopes in their otoliths, specifically the portion of their otolith formed during their larval stage, have been used to identify the natal origin. Complicating this work, however, is the fact that during this life stage, there is a shift in the source of isotopes deposited onto the growing otolith from maternally to environmentally derived. The objective of this study was to identify the portion of the otolith representing this transition to environmentally derived isotopes so as to accurately investigate questions of natal origin for a threatened population of fall Chinook salmon (Oncorhynchus tshawytscha). We exposed developing larvae to four treatments that differed in terms of their water strontium isotope ratio (87Sr/86Sr) and used change-point analysis of otolith 87Sr/86Sr and strontium to calcium ratio (Sr/Ca) to identify the otolith radius corresponding to the transition to environmentally derived isotopes. Our results indicated this transition occurred, on average, at 132 μm (87Sr/86Sr; ±50 μm standard deviation) and 127 μm (Sr/Ca; ±29 μm) from the otolith core, which corresponded to the developmental time between hatching and exogenous feeding. A substantial proportion of our otoliths (i.e., 61%) did not show convergence between otolith and water 87Sr/86Sr by the end of the 113-day experiment, which was likely due to the dietary contribution of marine-based feed. Therefore, we were unable to recommend an otolith radius to target for the purposes of reconstructing natal origin apart from being beyond approximately 130 μm. 相似文献
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在基础饲料中添加不同梯度的蛋氨酸钴(Co Met),制成钴含量分别为0.30 mg/kg、1.75 mg/kg、3.42 mg/kg、6.73 mg/kg、12.56 mg/kg、25.50 mg/kg的6组实验饲料(记作D1、D2、D3、D4、D5、D6组),饲喂初始体重(60.02±0.42)g的珍珠龙胆石斑鱼(Epinephelus lanceolatu♂×E.fuscoguttatus♀)幼鱼8周,研究蛋氨酸钴对其生长、矿物元素沉积和肝脏酶活力的影响。结果表明,随饲料中蛋氨酸钴含量的增加,实验鱼增重率(WGR)和特定生长率(SGR)均先升后降,D3组显著高于其他组(P0.05);饲料系数(FCR)先降后升,D3、D4组显著低于其他组(P0.05)。蛋氨酸钴对肌肉水分和灰分含量均无显著影响(P0.05);粗蛋白含量呈降低的趋势,D5、D6组显著低于D1~D4组(P0.05),但二者之间无显著差异(P0.05);粗脂肪含量先降后升,D4组显著低于其他组(P0.05),D6组显著高于其他组(P0.05)。肝脏、肠道、脊椎骨及肌肉钴含量均随饲料中蛋氨酸钴的增加而显著增加(P0.05);全鱼钴沉积率呈先升高后平稳的趋势,D1组显著低于其他组(P0.05)。肝脏铁、铜和锌含量随饲料中蛋氨酸钴的增加呈先升后降的趋势;肝脏锰含量显著降低(P0.05)。随饲料中蛋氨酸钴的增加,肝脏谷胱甘肽过氧化物酶(GSH-PX)活力先升后降,D5组显著高于其他组(P0.05);D5、D6组肝脏丙二醛(MDA)含量显著低于其他组(P0.05);肝脏精氨酸酶(DArg)活力随饲料中蛋氨酸钴的增加显著升高(P0.05);D4~D6组肝脏羧肽酶A(CPA)活力显著高于D1~D3组(P0.05),但三组之间无显著差异(P0.05)。本实验条件下,以SGR为评价指标,经折线回归分析,珍珠龙胆石斑鱼幼鱼对钴的最适需求量为3.25 mg/kg,即53.28 mg(Co Met)/kg(饲料)。 相似文献
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The effectiveness of the external marker yttrium oxide (Y2O3) and sampling period for determining the apparent digestibility (AD) of minerals and trace elements within Atlantic salmon feeds were compared. Yttrium oxide was compared at inclusions of 0.01, 0.1, 1 and 10 g kg?1 wet weight of the feeds. Samples were analysed for a range of mineral and trace elements via inductively coupled plasma optical emission spectroscopy after wet decomposition with concentrated nitric acid. Feed marked with 1 g kg?1 provided the greatest recovery, and provided analytical values within an optimal range, and therefore, the effect of faecal sampling period on AD of mineral and trace element was then compared using the feed marked with 1 g kg?1 Y2O3. Faeces were collected over three different time periods within a 24 h period: 4 × 6 h, 2 × 12 h and 1 × 24 h. Magnesium, manganese, phosphorus, iron and chromium displayed significant differences in AD relating to sampling period. An inclusion level of 1 g kg?1 Y2O3 and faecal sampling over at least an 18 h period after feeding proved to be the most effective method of determining AD of mineral and trace element in Atlantic salmon feed. 相似文献
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Determination of trace elements in otoliths of chum salmon Oncorhynchus keta by laser ablation-ICP-mass spectrometry 总被引:1,自引:0,他引:1
Trace element levels in the otoliths of chum salmon Oncorhynchus keta were examined by means of laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS). A close linear relationship
in the Sr/Ca ratios between X-ray analysis with an electron microprobe (EPMA) and LA-ICPMS analysis was found, suggesting
that the latter technique could be used to distinguish the marine and freshwater life phases. Mg, Zn, Ba and Sr concentrations
of the otoliths differed between the freshwater and seawater growth zones. Mg and Zn concentrations in the freshwater growth
zone were significantly higher than those in the seawater growth zone, while Sr and Ba concentration s in the former were
significantly lower than in the latter. The relationship between Sr concentration and Mg, Zn, and Ba concentrations at each
ablation showed significant correlations. These results suggest that trace element compositions may reflect differences between
freshwater and seawater environmental conditions. 相似文献