Oxygen Consumption and Ammonia Excretion of the American Eel Anguilla rostrata Fed Diets with Varying Protein Energy Ratios and Protein Levels

The effect of protein/energy ratio and protein level on utilization of protein and energy as indicated by oxygen consumption and ammonia production was investigated. When protein/energy ratio of the diet was optimum, there was no significant increase in ammonia production, indicating no increase in catabolism of protein for energy as protein levels increased. However, when the protein/ energy level was below optimum, there was a significant ( P < 0.05) increase in ammonia production as protein increased, indicating increased catabolism of protein for energy. However, there was no significant increase in oxygen consumption rate.     

大泷六线鱼地下海水室内养殖试验

在工厂化养鱼车间内使用沿海地下低恒温海水进行大泷六线鱼养殖试验,以了解大泷六线鱼生长的环境因子.结果表明:经过3个月的养殖,大泷六线鱼的总重量由放养时的388 kg增加到742 kg,平均成活率为92.8%,个体增重1.06倍;在不同密度下的瞬时生长率变动在0.0075～0.0115.除遗传因素外,养殖期间的水温及地下海水的水质也会对大泷六线鱼的生长有一定影响.     

Growth of Juvenile Green Sea Urchins,Strongylocentrotus droebachiensis,Fed Formulated Feeds with Varying Protein Levels Compared with a Macroalgal Diet and a Commercial Abalone Feed

The effects of varying protein and carbohydrate levels in prepared diets on the somatic growth of juvenile green sea urchins, Strongylocentrotus droebachiensis, were examined. Ten diets were tested on 600 hatchery reared urchins (mean start weight = 0.11 g) for 6 mo with three replicate groups per diet. Nine of the diets were prepared specifically for urchins and varied in protein (16–40% protein) and carbohydrate (29–49% carbohydrate) levels. The other two diets consisted of a commercially available abalone diet and the kelp, Saccharina latissima. Weight measurements were carried out at 6‐wk intervals, and at the end of the study urchins were individually weighed and a subsample from each treatment was analyzed for gonad weight and color. End weights after 6 mo ranged from 2.56 g for urchins fed the abalone diet to 6.11 g for urchins fed one of the prepared diets. Most of the prepared feeds outperformed kelp, and significant differences in growth were detected between some of the diets. In general, diets with lower protein levels (16–22% protein) and higher carbohydrate levels (>40% carbohydrate) produced the fastest growth. However, further diet refinement and/or use of finishing diets may be necessary to optimize gonad quality.     

在人工海水条件下，利用面包酵母培养褶皱臂尾轮虫（Brachionus plicatilis）的研究

在充气、以面包酵母为饵料、盐度为20的条件下,进行人工海水培养褶皱臂尾轮虫的实验。结果表明,不同人工海水中,用速溶海水晶配制成的海水和自然海水稀释的海水培养褶皱臂轮虫的效果明显地优于粗盐配制的;用速溶海水晶配制成的海水培养褶皱臂尾轮虫时,最大密度能达1710个／ml。不同营养强化剂中,绿色巴夫藻、扁藻以及胶囊肝油 蛋黄的效果较好。添加剂4ppm氯霉素时,培养褶皱臂尾轮虫的效果较好。     

海水土池育苗适口饵料生物培育技术

海水土池育苗可以利用池塘中天然饵料生物，因其具有成本低、收益好等特点而越来越受人们的欢迎。近几年来，河蟹土池育苗已兴起热潮，海水鱼类、贝类、虾蟹的土池育苗也已开始。但由于种种原因，土池育苗生产很不稳定，甚至失败，其中原因之一是育苗培育时饵料供应不足，营养不全面或是质量不好。浮游生物是多数鱼、贝、虾、蟹幼体的开口饵料、基础饵料，或是补充饵料，在育苗工作中起着重要的作用。搞好海水土池育苗，培育适口饵料生物是育苗的关键技术之一。在此介绍一些海水土池育苗中如何培育适口饵料生物的方法。     

聚己内酯在海水中降解性能的研究

研究聚己内酯(PCL)样条在海水中历经10个月的可降解性能。对每个月取样样品的降解性能通过凝胶渗透色谱(GPC)、差示扫描量热仪(DSC)、傅里叶红外光谱(FTIR)和力学性能进行评价,并对试样的内部形貌采用扫描电镜(SEM)进行观察。SEM照片显示,随着降解时间的增加,材料内部并没有出现明显空洞和裂纹,但样品淬断面变得平整,显示材料的脆性增加。GPC结果显示,随着在海水中降解时间的增加,样品分子量及其分布均逐渐减小;样条的力学性能下降,由于水分子的增塑作用,在海水中降解4~7月期间,样条的拉伸强度和断裂伸长率下降的趋势变缓。DSC分析显示,由于分子链段的断裂和优先降解无定形区域这两方面的共同因素,随着降解时间的增加,样品的结晶度略为增加。FTIR分析测试进一步证明了GPC和DSC的测试分析结果。分析表明PCL样品在海水中具有一定的降解性,但是降解速度较为缓慢。     

福尔马林药浴防治红鳍东方鲀异沟虫病的研究

异沟虫是红鳍东方鲀常见寄生虫之一,对红鳍东方鲀养殖业危害极大.为有效防治异沟虫病,在观察异沟虫虫卵孵化规律的基础上,研究评价福尔马林药浴对异沟虫的杀灭效果及其对红鳍东方鲀的安全性,形成红鳍东方鲀异沟虫病的防治方案.试验结果发现,异沟虫虫卵的孵化过程大致可分为孵化初期、孵化中期、孵化后期和破卵4个阶段,在17～19℃条件...     

池塘循环海水高效养虾试验

池塘循环海水高效养虾技术是一种集约化养殖模式。本试验以南美白对虾为饲养对象，经4个月（6-9月）管理，对虾产量为12000-14700kg/hm^2，出池规格达13.23-17.07g/尾，成活率80%-90%，纯收入84300-115200元/hm^2，投入产出比为1：1.6-1:2.5。     

Effects of Varying Dietary Protein Levels and Feeding Frequencies on Condition and Reproductive Performance of Channel Catfish to Produce Hybrid Catfish

The interspecific hybridization of channel catfish, Ictalurus punctatus, females with blue catfish, I. furcatus, males has been identified as a method to further improve production; however, lack of spawning success has affected its commercial application. To facilitate our understanding of the interaction of brood stock nutrition and reproductive performance, we evaluated the interaction of feed quality and feeding frequency. Channel catfish females were classified into two genetic groups, namely, high and low spawning. The treatments were offered during the spring season 70–90 d prior to the start of the spawning season. Induced reproduction was performed using luteinizing hormone releasing hormone analog. Condition of the fish as well as reproductive performance using spawning success, egg production, egg size, and fertilization at 48 h were determined. Changing protein level of the diet from 32 to 42% did not influence spawning, fecundity, or fertilization, but affected egg size and biochemical composition of the eggs. Increasing the feeding frequency from three to six times per week negatively affected spawning in one of the two genetics groups, did not affect egg production and egg fertilization, but had a significant effect on egg size. Older fish performed better than younger fish in terms of spawning success and egg production.     

千岛湖有机鳙鱼网箱暂养的体重损耗研究

本文研究了上市前的网箱暂养对千岛湖所产、经OFDC有机认证的鳙鱼的体重、丰满度及体重损耗率的影响。结果表明 ,在 6 7月水温逐渐升高 (2 4 30℃ )阶段 ,暂养鳙鱼的体重和丰满度均随时间呈指数式下降 ,而在 10 11月水温逐渐下降 (2 2 17.5℃ )阶段则随时间呈对数式下降。在不同暂养密度下和不同季节 ,鳙鱼的体重损耗率呈现不同的变化态势 :在 6 7月当暂养密度为 10 0尾 /箱 (2 72 7.6g/m3 )时 ,体重损耗率随时间呈指数式增加 ,而其他各高密度暂养组的体重损耗率均随时间呈对数式增长 ;在 10 11月 ,各密度组鳙鱼的体重损耗率均随暂养时间呈抛物线式变化 ,出现最大损耗率的时间各组均在 2 12 6d之间 ,最大损耗率出现的时间各组之间无显著差异 (P >0 .0 5 ) ,但损耗率极值的大小与暂养密度有一定关系。为了使暂养过程中的损耗降到最低 ,鳙鱼的适当暂养密度在 6 7月以 10 0尾 /箱 (2 72 7.6 g/m3 )左右为宜 ,而在 10 11月可以增加到 15 0尾 /箱 (35 97.2g/m3 ) ;暂养时间不宜超过 2 0d。     

Growth,Feed Conversion,and Nutrient Retention Efficiency of African Catfish,Clarias gariepinus, (Burchell) Fingerling Fed Diets with Varying Levels of Protein

Growth, feed conversion, and nutrient retention efficiencies of African catfish fingerling, Clarias gariepinus (5.22 ± .07 cm; 8.22 ± 0.03 g), fed diets with varying levels of protein were assessed by feeding seven casein/gelatin based isocaloric (17.62 kJ/g GE) experimental diets with graded levels of dietary protein (20%, 25%, 30%, 35%, 40%, 45%, and 50% of the diet) to triplicate groups of fish to apparent satiation for eight weeks. Effects of feeding these diets on live weight gain (LWG%), feed conversion ratio (FCR), protein efficiency ratio (PER), protein retention efficiency (PRE%), and energy retention efficiency (ERE%) were assessed. Maximum LWG% (867%), PER (2.01), highest PRE (32%), ERE (69%), best FCR (1.39), and maximum body protein were recorded in fish fed diet containing 35% protein. On the basis of the second-degree polynomial regression analysis of the above response variables, it is recommended that the inclusion of protein in the range of 34.4%–39.6% is optimum for maximizing growth potential, feed conversion, and nutrient retention in African catfish fingerling, Clarias gariepinus.     

福尔马林防治鮸鱼Miichthys miiuy(Basilewsky)刺激隐核虫(Cryptocaryon irritans)的研究

本文采用在淡水和海水中加入不同浓度的福尔马林,进行鮸鱼刺激隐核虫防治的研究.结果发现,福尔马林质量浓度为221.3 mg/L的海水中,鮸鱼12 h内无死亡,海水福尔马林对鮸鱼12 h,24 h,48 h,72 h,96 h时的半致死浓度分别为475.6,413.8,248.1,212.7,200.7 mg/L,安全浓度为56.08 mg/L;淡水浸泡鮸鱼的半致死时间为126 min;淡水处理刺激隐核虫的半致死时间为26 min,海水福尔马林中,处理2 h和12 h的半致死浓度为62.5,23.3 mg/L.全池泼洒20～80 mg/L福尔马林可防治刺激隐核虫,淡水浸泡30 min后泼 25 mg/L福尔马林效果更佳.研究结果表明,海水和淡水福尔马林对刺激隐核虫的致死浓度处于鮸鱼安全范围之内,淡水浸泡30 min后泼洒25 mg/L福尔马林可有效防治刺激隐核虫.     

Growth of Tilapia aurea in Seawater Cages

Fingerling Tilapia aurea were reared for 90 days in three 1.0 m³ floating cages in seawater (36 ppt) at Lee Stocking Island, Bahamas. Fish stocking density (100, 200 and 400 fish/m³) apparently did not affect growth rate but it appears salinity inhibited growth. Daily weight gain and specific growth rate (G) averaged 0.34 g/day and l.08%/day, respectively, for Tilapia aurea fingerlings. Infection of the Tilapia aurea by Bacillus sp. was associated with a significant number of mortalities. The relatively low growth rate and the high incidence of disease and mortality of Tilapita aures in seawater indicate that it may not be a good candidate for cage culture in full-strength seawater.     

海洋深层水在日本水产养殖中的应用概况

随着我国经济的飞速发展,人民生活水平的日益提高,人们对各种高档、稀有水产品的需求越来越多,为了满足这种需求,本文系统介绍日本海洋科技工作者利用海洋深层水养殖、培育高档鱼类方面所取得的部分成果,以供我国水产养殖科技工作者借鉴。     

Effects of Varying Dietary Protein and Lipid Levels on Growth Performance and Hepatocyte Changes in Juvenile African Cichlids (Pseudotropheus socolofi and Haplochromis ahli)

African cichlids are popular species produced commercially in South Florida for the aquarium trade. In their natural habitat, African cichlids show variations in feeding behavior, ranging from strict herbivory to omnivory to carnivory, and they are therefore excellent model species for nutrition work. The effects of varying dietary protein and lipid levels on the growth performance and hepatocyte changes of juvenile ornamental African cichlids were compared between Pseudotropheus socolofi, an omnivore, and Haplochromis ahli, a carnivore. It was hypothesized that the omnivore would have a lower protein requirement and show a higher incidence and severity of liver pathology when fed a high‐fat diet than the carnivore. Four diets were formulated using two crude protein (CP) levels (35–36% and 55–56% CP) and two lipid levels (8–10% and 19–20%), with resulting gross energy levels between 4000 and 5300 kcal/kg. P.socolofi (0.89 g, 4.1 cm) and H.ahli (2.1 g, 5.7 cm) were fed three times daily at 10% body weight per day (BW/d) for the first 3 wk, then 6% BW/d for the remaining 5 wks. Survival was greater than 86% for all treatments. Average weight gain of carnivorous H.ahli did not differ among the four diets and was greater than that of P.socolofi. P.socolofi grew larger when fed a high‐protein/high‐lipid diet compared to a high‐protein/low‐lipid diet or both the low‐protein diets. However, pathological changes to the liver were observed in P.socolofi fed a diet high in both protein and lipid. Carnivorous H.ahli tolerated higher levels of dietary lipid than the omnivorous P.socolofi. Both species showed significant growth, with no pathological changes occurring in the liver when they were fed a diet of 36% CP, 10% lipid, and 4000 kcal/kg gross energy.     

海水越冬池冰下浮游生物群落结构特征的研究

为了解海水越冬池浮游生物群落结构特征,对四口海水越冬池的主要理化因子及浮游生物状况进行了监测。共鉴定出浮游植物27种(属),其中常见或形成优势种群者主要有蛋白核小球藻、椭圆小球藻、布氏棕鞭藻、小环藻、前沟藻、海洋原甲藻、多甲藻、裸甲藻、光甲藻以及绿裸藻10种(属)。浮游植物总平均生物量为149.96mg/L,绿藻门所占比例最多,达97.87%,其分布状况是中、下层明显大于表层。原生动物和轮虫种类较少,前者主要为侠盗虫,平均数量为2737.3个/L,后者主要是喜冷疣毛轮虫和喜盐疣毛轮虫,平均数量为583个/L,分布特点均表层明显多于中、下层。桡足类种类主要有指状许水蚤、细巧华哲水蚤和近亲真宽水蚤等,数量上呈典型的下多上少的梯形分布。研究结果表明:浮游生物种、量及其分布状况是影响海水越冬池溶氧状况的关键因素之一。     

The Effect of Intravalvular Liquid Loss on Changes in Escherichia coli Levels in Live,Refrigerated Mussels (Mytilus galloprovincialis)

We investigated the effect of intravalvular liquid loss on changes in Escherichia coli (E. coli) levels in mussels (Mytilus galloprovincialis) harvested in different seasons and refrigerated (5°C) for 72 hours. A positive effect of seawater temperature at the time of harvesting on intravalvular liquid loss was found. No changes in E. coli levels in mussels (flesh and intravalvular liquid), as the result of intravalvular liquid loss, were observed. Levels of E. coli in the flesh decreased, probably as a result of cells dying off, causing the maintenance of E. coli levels in flesh and intravalvular liquid to be stable throughout storage.     

海产品甲醛的形成及其对鱼肉品质的影响

海产品是我国重要的农副产品资源,其安全性逐渐受到关注。近年来,"甲醛问题"给海产品带来了巨大的的经济损失,也一直是全社会关注的热点。目前已证实,海产品在贮藏加工过程中,在内生酶作用下会生成甲醛。综述了海产品甲醛的存在形式、影响因素及对鱼肉品质的影响。     

海水围塘生态栽培坛紫菜

紫菜（Porphym sp）原是生长在潮间带的岩礁上,尤其是在风浪大、潮流畅通的海区生长良好。经过多年的人工栽培,紫菜已适应于在潮间带和浅海的养殖筏架的栽培。坛紫菜（Porphyra haitanensis）作为浙江、福建海区常见的栽培藻类和重要的食用经济海藻,有近40年栽培的历史。但潮间带可以用作栽培坛紫菜的空间越来越小,必须开拓新的栽培空间。在围塘栽培紫菜则是一种新开拓的栽培方法。     

家用型水族箱养殖海水观赏鱼技术

海水观赏鱼以其怪异的体型、鲜艳的色彩,深受观赏鱼爱好者的青昧。家庭及办公场所海水观赏鱼饲养者常因养殖技术缺乏、经验不足而导致饲养失败。笔者结合自身养殖经验对水族箱的设置、观赏鱼品种的选择、水质指标的控制、饵料投喂及病害防治方面进行了分析与探讨,为家用型水族箱饲养海水观赏鱼提供技术支持。