不同盐度下3种罗非鱼的Na+-K+-ATPase活性比较

在盐度为0、10、20、30时测定了萨罗罗非鱼(Sarotherodon melanotheron)、尼罗罗非鱼(Oreochromis niloticus)和以色列红罗非鱼(Oreochromis sp.)鳃和肾中Na+-K+-ATPase活性。结果表明:(1)不同盐度对不同组织的Na+-K+-ATPase活性有显著影响,鱼的品种及其他交互作用对Na+-K+-ATPase活性均无显著影响;(2)在实验盐度范围内,无论是鳃和肾,萨罗罗非鱼、尼罗罗非鱼和以色列红罗非鱼的Na+-K+-ATPase活性均随盐度的升高而增高;3种罗非鱼中,萨罗罗非鱼的Na+-K+-ATPase活性随盐度的升高增大最为剧烈,以色列红罗非鱼次之,尼罗罗非鱼最小;低盐度时尼罗罗非鱼的Na+-K+-ATPase活性相对较高,高盐度时萨罗罗非鱼的Na+-K+-ATPase活性相对较高,Na+-K+-ATPase的活性与罗非鱼的耐盐能力有着一定的联系;(3)盐度大于7.19和11.94时,萨罗罗非鱼鳃中的Na+-K+-ATPase活性分别开始高于以色列红罗非鱼和尼罗罗非鱼;盐度大于18.42时,萨罗罗非鱼肾中的Na+-K+-ATPase活性开始高于尼罗罗非鱼;(4)除了在盐度20和30中的尼罗罗非鱼及盐度30的以色列红罗非鱼,是肾中的Na+-K+-ATPase活性高于鳃外,其他均为鳃中的Na+-K+-ATPase活性高于肾,肾中Na+-K+-ATPase活性在不同盐度之间的变化较鳃剧烈;罗非鱼的鳃比肾在渗透压调节上起的作用更大。     

温度对马来西亚红罗非鱼越冬期体色的影响

为了解马来西亚红罗非鱼体色分化变异的遗传分子机制,以期解决其越冬期的体色变异问题,本研究比较了越冬期不同温度处理(16、20、25和30°C)对其表观体色、酪氨酸酶活性以及皮肤色素带和黑色素细胞的影响。实验50 d后发现,16°C组大部分鱼体较实验开始时变黑,整个鱼体呈现青灰色,20°C组多数鱼体腹部也变为青灰色。随着温度的升高,红罗非鱼背部皮肤、腹部皮肤和血清中酪氨酸酶的活性逐渐升高,25°C时达到最高值,而随着温度的继续升高,30°C组鱼的酪氨酸酶活性反而降低。血液中tyr m RNA的表达量随着温度的升高而升高,25和30°C组红罗非鱼肌肉中的tyr m RNA表达量也显著高于16和20°C组。切片显微结构发现,随着温度的升高,红罗非鱼背部皮肤的黑色素细胞数量减少。研究表明,马来西亚红罗非鱼越冬期的体色变异可能是其皮肤黑色素细胞数量和体内酪氨酸酶活性改变的结果,深入研究其调控机制有助于了解鱼类体色遗传机理并进行体色性状的改良。     

海藻降血压肽的作用机制与制备

海藻是我国重要的海洋生物资源,因其含有丰富的活性物质成分而成为开发海洋药物研究的主要方向之一.来源于海藻中的降血压肽,安全无毒、无副作用,对预防和治疗高血压具有良好的效果.本文在介绍海藻中的降血压活性成分和降血压肽的作用机制的基础上,综述了海藻降血压肽的研究进展及其制备过程,并提出其开发应用前景.     

不同方法灭活的痢疾志贺氏杆菌菌苗对罗非鱼免疫原性的影响

用福尔马林、苯酚以及热灭活的痢疾志贺氏杆菌作为免疫原,分别接种尼罗罗非鱼后,通过测定受免鱼的血清凝集抗体效价、溶菌酶活性、补体C3、C4以及血液白细胞的吞噬活性,用痢疾志贺氏杆菌活菌攻毒的方法,探讨3种不同方法制备的免疫原对罗非鱼免疫原性的试验结果,结果表明,3种不同方法的免疫原对罗非鱼均具有较强的免疫原性,受免鱼的血液凝集抗体效价;与对照鱼相比,白细胞的吞噬活性明显上升,受免鱼对痢疾志贺氏杆菌活菌攻毒均产生了较强的免疫保护力.     

罗非鱼池轮养鳜鱼技术

罗非鱼不耐低温,秋末冬初,当水温降至15℃时,就不能继续生长。实际上罗非鱼养殖池只能利用半年(5～10月)。鳜鱼则不同,到了冬季并不完全停食,仍能持续生长,只是摄良减少,生长速度减慢。利用罗非鱼养殖池空闲期养鳜鱼,此阶段苗种便宜,饲料鱼丰富,鳜鱼养至翌年5月份上市,价格相对较高。盐都县义丰镇通过多年的生产实践,探索出利用罗非鱼池轮养鳜鱼的实用技术,有效地提高了池塘产出率,每0.067公顷(1亩)效益比单一养殖罗非鱼或鳜鱼增加3%以上。其具体技术如下。鳜鱼种放养罗非鱼养至8～9月份,大部分已达到上市规格(每尾400克左右),可以捕捞上市…     

牡蛎营养功能制品研究进展

牡蛎作为营养功能制品的原料在国内外得到了广泛的认可和应用。介绍了我国牡蛎资源的分布特征和丰富的营养价值,结合国内外牡蛎综合利用的研究进展,探讨了我国牡蛎营养功能制品的发展趋势,提出了开展牡蛎净化、危害物质脱除、过敏源脱除、活性物质高效分离提纯等共性关键技术研究方向,为我国牡蛎制品乃至整个贝类产业的发展提供了一种全新的思路。     

罗非鱼不同养殖系统对产出效果及异味物质含量的影响

对鱼菜共生系统、底排污系统、底排污+鱼菜共生3种养殖系统的水质变化和罗非鱼产出效果进行了分析,并利用微波蒸馏-吹扫捕集-气相色谱质谱联用技术检测了各系统水体中和罗非鱼肌肉中异味物质的含量变化。经过12周的养殖实验,对终重、生物量、特定生长率、饵料系数、增重率等指标进行测量比较,结果发现,罗非鱼的产出效果从优到差依次为:鱼菜共生组、底排污+鱼菜共生组、底排污组、对照组;底排污+鱼菜共生系统水体中溶解氧在各时期均最高,其亚硝氮、氨氮含量在各时期均最低;底排污或鱼菜共生系统均能有效降低养殖水体中异味物质2-MIB和GSM含量;对照组罗非鱼肌肉中异味物质含量最高,2-MIB和GSM分别达到(0.67±0.02)μg/kg和(0.870±0.018)μg/kg,而底排污+鱼菜共生组罗非鱼肌肉中异味物质含量在各时期最低,2-MIB和GSM分别为(0.31±0.02)μg/kg和(0.53±0.042)μg/kg。结果表明,在罗非鱼精养池塘中,可通过底排污和鱼菜共生结合,降低水体中和罗非鱼体内异味物质的累积,提高其经济价值。     

罗非鱼血液指标同营养关系的研究

罗非鱼是我国工厂化养殖的主要对象,在北方不少地区利用电厂余热及温泉地热养殖罗非鱼己获成功。近年来,随着生产的发展,各种人工配合饵料及其添加剂应运而生,然而它们是否能满足鱼类的营养需要、以及如何评价其营养价值,这都是养殖工作者所关注的问题。国内外许多学者曾对鱼类的血液指标进行过研究,薛艳庄等(1963),林光华(1979),赵明蓟(1979)和日本尾崎元雄等(1982),曾报导鱼类(青鱼、草     

混养罗非鱼对对虾池浮游生物群落结构的影响↑（*）

关于滤食性或杂食性鱼类对水体浮游生物群落结构的影响,国内外已做过很多工作。罗非鱼作为以浮游生物为主的杂食性鱼类不仅能够直接利用水体中的浮游生物等天然饵料,还通过自身的摄食和代谢活动对浮游生物群落结构产生影响［１～４］。Ｄｒｅｎｎｅｒ等［５］研究罗非鱼在Ｋｉｎｎｅｒｅｔ湖中对浮游生物的摄食选择性后指出,罗非鱼对浮游动物和大型浮游植物具有压制作用,同时能促进超微浮游植物的发展。因此养殖池塘中放养一定数量的罗非鱼,不仅能够提高池塘的物质利用效率,还会起到稳定养殖环境的作用。本文结合台湾红罗非鱼（Ｏｒｅ…     

雌性特异蛋白复合物促进鱼类性腺发育及提高孵化率的研究

我们从1980年起开始探索鱼类性腺发育和卵子发育过程中的化学变化,并进行了鱼类血液化学和血液生理学的研究,发现鲫鱼、鳊鱼、罗非鱼、梭鱼的血清蛋白中,雌鱼血清多1条或2条蛋白带,而雄鱼的血清蛋白则未发现此带。同时我们对鱼的性腺发育及卵子成熟过程中物质代谢进行了     

罗非鱼综合加工利用与质量安全控制技术研究进展

经过多年发展,目前中国罗非鱼产业正处于从规模产量型向质量效益型转变的关键时期,对罗非鱼原料进行高值化综合加工利用,同时确保产品的质量安全,是提高中国罗非鱼产业竞争力的必由之路。要实现这一目标必须依靠技术创新来实现产业升级,以保障中国罗非鱼产业可持续稳定发展。文章综述了近年来国内外在罗非鱼综合加工利用与质量安全控制方面的研究进展及发展趋势,旨在为中国罗非鱼产业的健康发展提供参考与借鉴。     

Influence of dietary l-carnitine on growth, biological traits and meat quality in Tilapia

This study was designed to determine whether l -carnitine supplementation is necessary in a tilapia diet containing low-fish meal and a high lipid level, which is beneficial economically and for the environment. The effects of dietary l -carnitine on the growth, body composition, blood traits and post-thaw drip from muscle in hybrid tilapia were investigated. Five isonitrogenous and isocaloric diets were fed to the fish with a mean body weight of 141.7 g for 168 days. The control diet contained fish meal as the major protein source with 7% lipid. Other diets contained 7% or 12% lipid, in which fish meal was largely replaced by plant proteins, and supplemented with l -carnitine or not. Results showed that supplemental dietary l -carnitine did not affect the growth performance, feed efficiency or protein efficiency ratio, while the supplementation significantly reduced the mesenteric fat ratio. Whole body and muscle proximate compositions were unaltered by any dietary treatment. The total plasma lipid, triacylglycerol and cholesterol values of tilapia fed diets with alternative plant proteins were significantly lower than those of the control fish, whereas increasing the dietary lipid content increased the aforementioned blood traits. A decrease in plasma ammonia and an increase in urea were observed in dietary l -carnitine-supplemented fish. Post-thaw drip from muscle was reduced in fish fed supplemental dietary l -carnitine. The observations of this study revealed that neither the growth performance nor the feed utilization of hybrid tilapia was improved by a dietary l -carnitine treatment, but that it did lead to a reduced mesenteric fat ratio, altered nitrogen metabolism and improved meat quality.     

加州鲈肌肉生长抑制素(MSTN)cDNA的克隆和序列分析

肌肉生长抑制素是抑制肌肉生长和发育的生长调控因子。对运用RT-PCR和RACE技术从加州鲈成鱼肌肉总RNA中扩增得到的MSTN cDNA全序列进行了序列分析。结果表明,加州鲈MSTN cDNA全长为1626bp,其开放阅读框为1 134bp,共编码377个氨基酸,前面的22个氨基酸为信号肽,中间有四个氨基酸(RARR)为蛋白水解加工位点;该基因总共有13个半胱氨酸残基,后面9个在蛋白水解加工位点之后的C端生物活性区,与其它脊椎动物比较,它们的位置完全一致,对该基因的结构和功能非常重要。与GenBank中已知的条纹狼鲈、金鲷、斑马鱼、虹鳟、斑点叉尾鮰、人、猪、鸡、鸽MSTN的ORF相比较,核苷酸序列同源性为63%~94.4%,氨基酸同源性为61.4%~96%,特别是在C端生物活性区氨基酸同源性为88.1%~100%,高度的保守性反映了该基因受到了高度的进化限制以及功能的重要性。加州鲈MSTN基因的克隆为研究该基因打靶和鱼类肌肉发育调控机理奠定了基础。     

Performance of genetically improved Nile tilapia compared with red hybrid tilapia fed diets containing two protein levels

A 10‐week feeding trial was conducted to investigate the interaction between tilapia genotype and dietary protein level on the growth, feed utilization efficiency and body composition of Nile tilapia [Oreochromis niloticus L., F₉ generation of genetically improved farmed tilapia (GIFT) strain] and red hybrid tilapia (Oreochromis sp.). Two isoenergetic diets (15.5 kJ g⁻¹ diet) containing 25% or 35% crude protein were formulated and fed to triplicate groups of tilapia (12.8±0.2 g) at a fixed daily ration of 4% of their body weight. The growth performance of the GIFT tilapia fed 25% or 35% dietary protein was significantly higher (P<0.05) compared with red tilapia at either protein level. Increasing the dietary protein level by 10% led to a further 10% increase in the final weight of GIFT tilapia but no further increase was observed in the weight gain of red tilapia. Growth was influenced by the interaction between diet and tilapia genotype. Feed conversion ratios were 14% and 33% better in GIFT tilapia compared with red tilapia fed the 25% or 35% protein diet respectively. Protein efficiency ratio and net protein utilization were influenced by both diet and tilapia genotype, but not the interaction between the two. The apparent digestibility coefficients of dry matter and protein did not differ significantly between the two diets and tilapia genotypes but lipid digestibility was 1.2–4.7% higher for the GIFT tilapia. Tilapia whole‐body protein content was significantly influenced by both diet and tilapia genotype. The higher growth potential, better feed utilization efficiency and higher body protein content of GIFT tilapia compared with red tilapia should have a positive impact on tilapia farming in terms of production costs.     

加工鱼产品种类的电泳鉴定

介绍了几种鱼的白肌在乳酸脱氢酶和蛋白电泳表型上种的特异特征。链，镛，草，青，尼罗罗非鱼白肌乳酸脱氢酶的谱带数不同，活性强度亦不同；蛋白质电泳图谱的迁移率也有差异。这类特征可为加工产品的种类鉴定提供可靠判据。鱼类电泳鉴定技术的标准化及其应用将为规范鱼品加工业，检验鱼产品提供理想的检测手段。     

Effect of Dietary Ginseng Herb (Ginsana® G115) Supplementation on Growth, Feed Utilization, and Hematological Indices of Nile Tilapia, Oreochromis niloticus (L.), Fingerlings

The present study was conducted to evaluate the effect of dietary ginseng herb (Ginsana^® G115) supplementation on growth performance, feed utilization, and hematological indices of Nile tilapia, Oreochromis niloticus (L.), fingerlings. A total of 378 Nile tilapia fingerlings with an average body weight of 24.4 ± 0.2 g were divided in the six experimental treatments (three replicates each). The experiment was conducted for 17 wk. Six isonitrogenous, 27.2% digestible protein and isocaloric, 12.3 MJ/kg digestible energy experimental diets were formulated. The control diet had no Ginsana G115 added. Diets 2–6 each contained Ginsana G115 at levels of 50, 100, 150, 200, and 250 mg/kg, respectively. Growth performance and feed utilization efficiency of Nile tilapia were significantly (P ≤ 0.05) higher in all treatments receiving Ginsana G115‐supplemented diets than the control diet. Red blood cells counts, hematocrit, and hemoglobin significantly (P ≤ 0.05) increased with increasing dietary Ginsana G115 levels compared to those of the control diet. The same trend was observed for total plasma protein and total plasma globulin levels. The results of present study suggested that Nile tilapia fingerlings fed diets containing at least 200 mg/kg Ginsana G115 for 17 wk had enhanced growth performance, diet utilization efficiency, and hematological indices.     

Changes in purine content of tilapia surimi products during processing

ABSTRACT:   Changes in purine-related compounds of tilapia surimi product during processing were investigated. The washing step could result in about 60% decrease of total purine content in tilapia mince during processing. The main released purine substance was inosine monophosphate. The major reducing effect was conducted in the first 10 min during washing. No significant changes were observed after washing for 20 and 30 min. The lowest total purine content of tilapia surimi product was obtained with repeating the washing step twice. Thus, this procedure could reduce the purine content of tilapia mince from a high purine content level to a middle level. The gel strength of tilapia surimi product increased with increasing washing duration within 30 min. However, tilapia surimi product with a middle purine content and acceptable gel strength might be produced by washing twice in 10 min during processing.     

响应面法优化复合咸味剂腌制罗非鱼片的工艺

为开发一种低盐健康新型的使用复合咸味剂腌制罗非鱼片的加工技术,本研究以罗非鱼片为原料,通过单因素实验,考察氯化钠分别与氯化钾、苹果酸钠、白砂糖不同添加量组合对腌制罗非鱼片的感官品质、含盐量、水分含量、蛋白水解指数和质构的影响,采用Box-Behnken响应面法优化复合咸味剂的最佳配比参数。结果显示,氯化钾、苹果酸钠、氯化钠添加量对罗非鱼片品质影响显著,白砂糖添加量对罗非鱼片品质影响不显著;通过Box-Behnken响应面法优化得到复合咸味剂腌制罗非鱼片的最佳工艺条件:氯化钾添加量为2.6%、苹果酸钠添加量为1.3%、氯化钠添加量为9.1%、白砂糖添加量为0.5%。优化后产品的感官评分为89,含盐量为2.81%,表明实验模型可以用于预测实际值。研究表明,与对照组相比,产品的钠含量降低了22.92%,从而为罗非鱼的加工提供了一种低盐低钠快速腌制的加工新技术。     

罗非鱼皮明胶的脱腥方法及理化性质

以罗非鱼鱼皮明胶为原料,通过感官评定比较活性炭吸附法、酵母菌发酵法及乳酸菌发酵法的去腥效果,从中筛选出适宜的脱腥方法;采用正交试验探讨不同的脱腥条件对明胶溶液透明度及腥味感官评分值的影响。同时对经脱腥处理后的明胶进行理化性质分析,并利用同时蒸馏萃取与气相色谱-质谱(GC-MS)联用技术测定其挥发性成分,为工业化制备无腥味罗非鱼皮明胶提供理论依据。结果表明:活性炭吸附法、酵母菌发酵法及乳酸菌发酵法均对明胶溶液具有脱腥作用,它们之间的脱腥效果差异显著(P(0.05),其中以活性炭吸附法脱腥效果最好。正交试验确定的活性炭吸附脱腥的适宜条件为添加1.5%(w/v)活性炭到5%(w/v)明胶溶液中,40℃吸附30min。经脱腥处理后制得的明胶无腥味,粗蛋白含量为91.3%,凝胶强度高达301g,透明度增加,水不溶物减少;GC-MS分析结果显示,明胶溶液脱腥前检出的挥发性成分有33种,其中大部分是酯类物质,其次是醇类、酮类和烯类等物质,明胶溶液脱腥后检出的挥发性成分有26种,种类及相对含量比脱腥前的少,减少的主要是烯类和酮类物质。研究表明,活性炭吸附法能有效去除明胶的腥味,改善其理化性质,可应用于工业化生产无腥味罗非鱼皮...     

Exploring the trophic structure in organically fertilized and feed-driven tilapia culture environments using multivariate analyses

Reports of similar yields in manure and feed‐driven tilapia culture environments raise questions on food utilization in these environments. The possibility that similar production rates are because of utilization of different foods was investigated using exploratory techniques of multivariate analyses. Using factor analysis, trophic pathways through which food becomes available to fish were explored, and using anova models, water quality, sediment quality and tilapia growth and yields were compared. Conceptual graphic models of the main ecological processes occurring in feed‐driven and organically fertilized environments are presented and discussed. In both environments, autotrophic and heterotrophic pathways are important processes that result in the availability of natural foods that are utilized by the fish. Extrapolated fish yield data indicate that with equal nutrient input and stocking density, organically fertilized environments could achieve production rates similar to those in feed‐driven environments. The general assumption that supplemental or complete foods are well utilized by tilapia in outdoor stagnant ponds remains challenged, and further research on tilapia feeding behaviour and food selection in feed‐and organic fertilizer‐driven environments is needed.