Effects of ultrasonic treatment on collagen extraction from skins of the sea bass Lateolabrax japonicus

In this study we investigated the effects of ultrasonic wave treatment on the extraction yield of acid-soluble collagen from sea bass skins. Two extraction methods were compared: a 24 h acid treatment using 0.5 M acetic acid (1:200 sample/acid, w/v) and an extraction using ultrasonic treatment after the addition of a 0.5 M acetic acid solution. The results indicated that the extraction yield of collagen increased with the ultrasonic treatment, with the extraction rate increasing rapidly at higher amplitudes of ultrasonic treatment. The subunit compositions of the collagen extracted by ultrasonic treatment were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, which revealed that the α1(α3), α2, and β chains of collagen were present early in the ultrasonic treatment. An unknown component, believed to be a product of collagen degradation induced by the ultrasonic treatment, was detected only after a longer treatment time. The component extracted by the ultrasonic treatment was determined to be collagen based on the finding that there were no changes in the main components of collagen, specifically, the α1(α3), α2, and β chains, following pepsin treatment.     

Nocardiosis in sea bass, Lateolabrax japonicus, in Taiwan

An epizootic in pond cultured sea bass, Lateolabrax japonicus , was caused by Nocardia sp. in Taiwan, in September and October 1997. The cumulative mortality within 1 month was 17.5% (3500 out of 20 000 fish) and diseased fish were 7 months old with total lengths from 25 to 30 cm. Multiple, yellowish white nodules, 0.1–0.2 cm in diameter, were scattered in the gill, heart, liver, spleen and kidney. Histopathologically, typical granulomatous lesions appeared in those organs. The morphology of isolated bacteria from brain heart infusion (BHI) medium or Lowenstein–Jensen medium (LJM) were bead-like filaments, as shown by Ziehl-Neelsen's (ZN) staining method. The gross lesion and histopathological changes found in experimentally infected fish were similar to those in naturally infected fish. Based on the growth characteristics, morphological and biochemical properties of the bacterium, and histopathological changes, the isolated bacteria were identified as Nocardia seriolae . This is the first report of N. seriolae -infected sea bass in aquaculture.     

渤海鲈鱼人工繁殖技术

鲈鱼又叫花鲈 ,中国鲈 ,为我国重要名贵经济鱼类。苗种来源以自然海区为主 ,尤其是渤海产天然苗种生长快 ,对盐度适应性强 ,倍受各地养殖户的青睐。但由于对苗种的过度捕捞 ,使渤海鲈鱼资源急剧衰退 ,因此 ,人工繁殖鲈鱼苗种对保护鲈鱼资源 ,促进人工养殖的健康发展是非常重要的。我们连续两年对渤海鲈鱼进行了生产性人工繁殖都取得了可喜成果。 2 0 0 1年培育后期仔鱼1 1 0万尾 ,2 0 0 2年培育了 3～ 5cm幼鱼 2 0余万尾 ,现将渤海鲈鱼人工繁殖的有关技术总结如下 :1　亲鱼来源　采捕于渤海湾南部和西部海区 ,雌雄都在 4龄以上 ,体重雌性 6…     

鲈鱼人工繁殖育苗试验

<正> 近几年,鲈鱼资源明显减少,单靠从海里捞取天然鲈鱼苗种已不能满足养殖生产需要。因此,我们开展了对鲈鱼的人工繁殖和孵化育苗试验,并获得苗种25.3万尾。 1 试验材料及方法 1.1 亲鱼的来源及选择 所用亲鱼是2000年11月15—22日陆续从渤海海区专门捕捞的,从中挑选没有产过卵、体质健壮、无病、体表无伤、体重3kg(4龄)以上的雌性鲈鱼5尾、雄鱼8尾投放在船上早已准备好的帆布篓中,采用换水法和尼龙袋补充纯氧,以保持水中溶解氧。将亲鱼运至滦南县会达水产养殖公司工厂化海水育苗池暂养,供繁殖用。亲鱼入池前用5×     

培育花鲈苗种投饵率分析

近年来随着花鲈自然资源的日趋减少与消费需求的日益增加,花鲈的人工养殖业已经逐渐为人们所重视。国内目前花鲈的养殖苗种主要依靠天然资源,放养的规格小,质量差,成活率低。针对这种情况我们把花鲈苗种在工厂化车间里进行强化中间培养。使养成的鱼种质量提高,规格增大,成活率上升。本文主要是通过对花鲈苗种培育期间的不同投饵率的比较,以求得一个最佳的投喂量。     

海鲈游泳续航时间和运动代谢规律研究

为研究海鲈(Lateolabrax japonicus)的游泳续航能力和游泳过程中的物质代谢规律,以深水网箱养殖的3月龄海鲈为研究对象,采用游泳续航时间和生化指标作为评测海鲈游泳能力和代谢规律的方法进行了试验。结果显示,海鲈的游泳续航时长为200 min,其续航能力强于大黄鱼而弱于美国红鱼。在游泳过程中,海鲈血糖浓度升高,但差异性不显著(P>0.05),肌糖原随着时间的增加显著减少(P<0.05),且肌糖原浓度在海鲈疲劳时接近于0。当鱼接近100%疲劳时,其肝糖原浓度也接近于0;当海鲈以不同疲劳程度游泳时,其肌肉乳酸脱氢酶浓度会显著升高(P<0.05)。表明海鲈的续航游泳过程伴随着无氧呼吸和有氧呼吸。     

壳聚糖对花鲈生长和非特异性免疫力的影响

在基础饲料中分别添加0.5%、1%和2%的壳聚糖,连续投喂花鲈(Lateolabrax japonicus)60d,探讨壳聚糖对花鲈生长和非特异性免疫力的影响。结果表明,添加0.5%和1%壳聚糖可以显著促进花鲈的生长,但是不同添加浓度对成活率均无影响。在30d时添加0.5%或1%壳聚糖能有效提高花鲈的补体活性、溶菌酶活性和吞噬活性;在60d时仅明显提高补体活性。添加壳聚糖对白细胞的数量没有影响。     

温,盐度对鲈鱼早期仔鱼生长及存活率的影响

本文就温度，盐度以及不同降低盐度方法对鲈于仔鱼的生长及存活进行实验，经一星期的培养，结果表明，１；钙鱼仔鱼在盐度３０－３‰的海水中都能生长，以２０‰的存活率最高达９９％。２．每经６小时逐渐降低盐度５‰的仔鱼存活率高于大幅度骤降盐度。３．温度１４．７－１４．９℃和１８．３－１９．７℃，以盐度３０‰生长快，５‰生长缓慢。     

中草药对鲈鱼诱食活性的研究

以鲈鱼为实验对象,采用迷宫装置研究中草药单体及中草药复合剂对鲈鱼Lateolabrax japonicus(Cuvier et Valencinnes)的诱食活性.结果表明,中草药单体的诱食效果比中草药复合剂诱食效果好.不同的中草药单体对鲈鱼的诱食效果差异明显,阿魏对其有显著的诱食作用,陈皮的诱食作用次之.同时发现鲈鱼对肉桂、白芷、山楂和大茴香有一定的趋避反应.不同的中草药复合试剂对鲈鱼的诱食效果差异较大,其中,中草药组合栀子 陈皮 阿魏对鲈鱼有显著的诱食作用,而中草药组合陈皮 栀子对其有显著的抑制作用.     

Growth performance,digestive enzyme activity and immune response of Japanese sea bass,Lateolabrax japonicus fed with fructooligosaccharide

In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg.     

复合微生态制剂对花鲈非特异性免疫力及抗病力的影响

将复合微生态制剂以0(control)、500mg/kg(PR-500)和3000mg/kg(PR-3000)的添加量加入到花鲈(Lateolabraxjaponicus)基础饲料中,在饲喂42d和84d后分别取样,以血清溶菌酶活力、替代补体活力(ACH50)、头肾巨噬细胞杀菌力及呼吸爆发活力为判据,确定微生态制剂对花鲈非特异性免疫力的影响;用鳗弧菌Vibrio anguillarum对饲喂84d后的花鲈进行攻毒实验,测定累积死亡率,以确定微生态制剂对花鲈抗病力的影响。结果表明,饲喂84d时,实验组的特定生长率(SGR)较对照组有增高的趋势,但与对照组间无显著性差异(P>0.05)。饲喂42d时,实验组花鲈的血清溶菌酶活力与对照组相比无显著性差异(P>0.05);84d时,实验组的溶菌酶活力显著低于对照组(P<0.05)。饲喂42d与84d时实验组花鲈的替代补体活力(ACH50)与对照组相比无显著性差异(P>0.05);饲喂84d时,实验组花鲈巨噬细胞的呼吸爆发活力与对照组相比无显著性差异(P>0.05);PR-3000组花鲈的巨噬细胞杀菌力显著高于对照组(P<0.05);实验组花鲈的头肾巨噬细胞数量显著高于对照组(P<0.05)。攻毒实验结果显示,对照组花鲈最早出现死亡;攻毒后第27~32h期间,对照组花鲈的累积死亡率显著高于实验组(P<0.05)。     

不同饲料对花鲈饲养效果的比较研究

选用８种饲料－－鱿鱼、环棱螺、舌鳎、鲫鱼、海虾、螯虾、硬颗粒及软颗粒饲料，对花鲈鱼种进行饲养试验，比较不同饲料的生长效果。结果表明，花鲈鱼种的日增重率与所摄取食物的干重占体重的百分比呈直线正相关；８种饲料以软颗粒饲料的饲料系数最低，为０．８８，其能量利用效率最高，达３１．３１％。     

饲料中蛋白寡聚肽对鲈鱼和小白鼠蛋白消化率和蛋白沉积率的影响

分别以新鲜冷冻和20℃解冻放置48h太平洋狭鳕(Pollacbiuspollacbius)下脚料为原料,酶解、冷冻干燥后获得蛋白寡聚肽FPH-1、FPH-2;新鲜冷冻太平洋狭鳕下脚料直接冷冻干燥获得对照组蛋白FPR。通过小白鼠和鲈鱼实验,比较测定3组蛋白源的蛋白消化率和蛋白沉积率。分别以蛋白寡聚肽FPH-1、FPH-2和FPR配制饲料饲喂小白鼠10d,3组蛋白源之间AD、TD、NPU、BV值无明显差异(P>0.05);以蛋白质水解度DH=35.6%的蛋白寡聚肽FPH-1按0、4.2%、12.4%、21.2%的比例分别替代饲料中的蛋白质配制饲料饲喂鲈鱼60d,FPH-1替代饲料蛋白比例为12.4%时,特殊生长率(SGR)和蛋白沉积率最高(P<0.05),但当FPH-1替代饲料蛋白比例提高到21.2%时,其促生长效果和蛋白沉积率反而表现出降低趋势。     

花鲈弧菌病病原菌（哈维氏弧菌）的分离与鉴定

1999年4－5月，山东省青岛市胶南海区网箱养殖场花鲈（Lateolabrax japonicus)幼鱼发生暴发性传染病，死亡率达50％。从具有明显症状的病鱼的病灶组织分离到1株优势菌SF－1，经人工感染和从人工感染发病的花鲈再分离的SF－3菌株的再感染试验结果表明，所分离的菌株为此次花钙烂层病的致病菌，经形态、生理生化等64项特征指标鉴定，SF－1和SF－3均为哈维氏弧菌（Vibrio harveyi)。药敏试验结果表明，头孢噻肟，头孢三嗪，头孢孟多，呋喃妥因，氯霉素,氧哌嗪青霉素，磺胺类，复方磺胺、三甲氧苄氨嘧啶，多粘菌素E等10种药物对该菌株有明显的抑制作用。     

花鲈不同养殖群体的遗传结构分析

采集我国花鲈(Lateolabrax maculatus)主要养殖地区山东(青岛市和东营市)、浙江(宁波市)、福建(福鼎市、漳州市梅岭镇、漳州市桥东镇和漳州市东山县)、广东(珠海市斗门区)的86尾个体作为实验对象,结合已报道的花鲈野生群体的遗传研究背景,通过ddRAD简化基因组测序对以上花鲈养殖群体进行遗传结构分析。主成分分析(PCA)与遗传组分分析结果(最佳聚类K值为2)均显示,8个花鲈养殖群体与天津、烟台和文登的野生群体间遗传差异较小,表明我国花鲈养殖群体主要为黄、渤海种质来源。8个养殖群体间遗传分化分析结果显示,福建漳州梅岭镇和桥东镇的2个养殖群体与其他养殖群体间出现显著的遗传差异,表明所检测的养殖群体内部也出现了一定程度的分化。本研究结果可为我国从山东到广东(从北到南)的花鲈养殖群体遗传结构分析提供参考,为后续花鲈种质资源的保护、育种工作提供依据。     

Optimizing dietary protein sources for Japanese sea bass (Lateolabrax japonicus) with an emphasis on using poultry by‐product meal to substitute fish meal

This study evaluated the potential of using poultry by‐product meal (PBM) to replace fish meal in diets for Japanese sea bass, Lateolabrax japonicus. Fish (initial body weight 8.5 g fish^?1) were fed six isoproteic and isoenergetic diets in which fish meal level was reduced from 400 g kg^?1 (diet C) to 320 (diet PM1), 240 (diet PM2), 160 (diet PM3), 80 (diet PM4) or 0 g kg^?1 (diet PM5), using PBM as the fish meal substitute. The weight gain (WG), specific growth rate, nitrogen retention efficiency, energy retention efficiency and retention efficiency of indispensable amino acids were higher in fish fed PM1, PM2, PM3 and PM4 diets than in fish fed diets C or PM5. The phosphorus retention efficiency was lower in fish fed PM3, PM4 and PM5 diets than in fish fed C, PM1 or PM2 diets. Fish fed diet PM5 had the highest feed conversion ratio, total nitrogen waste output (TNW) and total phosphorus waste output (TPW) among the treatments. No significant differences were found in the hepatosomatic index or body contents of moisture, lipid and ash among the treatments. Fish fed diet C had lower condition factor and viscerosomatic index than those of fish fed PM1, PM3, PM4 and PM5 diets. The results of this study indicate that using fish meal and PBM in combination as the dietary protein source produced more benefits in the growth and feed utilization of Japanese sea bass than did using fish meal or PBM alone as the dietary protein source. The dietary fish meal level for Japanese sea bass can be reduced to 80 g kg^?1 if PBM is used as a fish meal substitute.     

养殖日本真鲈和大口黑鲈原料特性比较

为了解养殖海水鲈鱼日本真鲈(Lateolabrax iaponcas)和淡水大口黑鲈(Micropterus salmoides)原料特性及加工可适性,测定了养殖日本真鲈和大口黑鲈的形态参数、基本成分、蛋白质组成、p H值、采肉率、熟肉率、系水力、滴水损失、鱼肉色泽和质构参数,并对养殖日本真鲈和大口黑鲈原料特性进行比较分析。结果表明:日本真鲈和大口黑鲈的形体参数和色泽差异显著(P0.05),两者的鱼头、鱼骨和内脏所占比例均较高;粗脂肪含量差异较大(P0.05),大口黑鲈粗脂肪含量是日本真鲈的2.70倍;粗蛋白总含量差异不大,但各种蛋白的含量有显著性差异(P0.05),日本真鲈的总基质蛋白含量高于大口黑鲈;大口黑鲈鱼肉较日本真鲈p H略低,熟肉率低,滴水损失率和失水率分别为日本真鲈的2.20倍和2.06倍;大口黑鲈和日本真鲈的质构参数均存在显著性差异(P0.05),大口黑鲈质构特性优于日本真鲈,口感较好。综合分析表明日本真鲈适合加工鱼糜等产品,而大口黑鲈适合生鱼片、鱼片等加工。两种鱼在加工过程中产生的下脚料较多,应合理利用下脚料提高其附加值。     

鳗弧菌口服微胶囊疫苗的制备及其对鲈鱼的免疫效果

以分离自患病鲈鱼(Lateolabrax     

Outbreak of hirame rhabdovirus infection in cultured spotted sea bass Lateolabrax maculatus on the western coast of Korea

In this study, we determined the cause of a disease outbreak in spotted sea bass, Lateolabrax maculatus reared in culture cages on the western coast of Korea in 2013. The major signs in the diseased fish exhibited were haemorrhaging on the membranes of the abdomen, gastrointestinal organs and opercular gills, as well as an enlarged spleen. No external morphological signs of infection were visible, except for a darkening in colour. No parasites or pathological bacteria were isolated from the diseased fish; however, epithelioma papulosum cyprini (EPC) cells inoculated with tissue homogenates from the diseased fish showed cytopathic effects (CPEs). Virus particles in the EPC cells were bullet‐shaped, 185–225 nm long and 70–80 nm wide, characteristic of Rhabdoviridae. Polymerase chain reaction analyses of homogenized tissues from the diseased fish and supernatants of cell cultures with CPEs indicated specific, 553‐bp‐long fragments corresponding to the matrix protein gene of the hirame rhabdovirus (HIRRV). Phylogenetically, the HIRRV phosphoprotein gene of spotted sea bass was more closely related to phosphoproteins from Chinese and Polish HIRRV strains than from other Korean strains. To our knowledge, this is the first report of HIRRV infection in cultured spotted sea bass.