三疣梭子蟹对饵料鱼和蛤摄食参数的研究

研究体重为(9.20±1.50)g的三疣梭子蟹在分别投喂饵料鱼和兰蛤及有无沙底质条件下的昼夜摄食节律、摄食率和昼夜摄食量的差异.结果表明:投喂兰蛤组的三疣梭子蟹摄食高峰在20:00左右,投喂饵料鱼组三疣梭子蟹的摄食高峰在02:00左右;沙底质条件下三疣梭子蟹的夜晚摄食量占全天摄食量的94.34%,而无底质组为75%,表明在潜底环境条件下三疣梭子蟹具有更明显的昼夜摄食节律;投喂兰蛤组三疣梭子蟹黑夜摄食量比值显著高于白天,分别为75%和25%,而投喂鱼组黑夜摄食量比值仅略高于白天,分别为59.21%和40.79%.此外,投喂鱼组白昼摄食率可达80%,显著高于投喂兰蛤组的10%,表明投喂鱼饵料有利于三疣梭子蟹的白昼进食.根据昼夜摄食量对比分析,建议采用白昼投喂占总投喂量20%～30%的鱼肉以降低蜕皮残食,夜晚投喂70%～80%的兰蛤的投喂策略促其生长,并减少梭子蟹的残食.     

Feeding behaviour of adult Centropages hamatus (Copepoda, Calanoida): Functional response and selective feeding experiments

The feeding behaviour of adults of the marine calanoid copepod Centropages hamatus was studied in laboratory experiments with ciliates and phytoplankton as food sources. The ingestion rate of algal (flagellates, diatoms) and ciliate prey (oligotrichs) as a function of prey concentration could be described by a Holling type III functional response, with close to zero ingestion rates at concentrations below 5 µg C l^− 1. In general, ingestion of ciliates was higher than ingestion of algae, and maximum feeding rates by adult males reached were half the feeding rates of adult females at prey concentrations exceeding 50 µg C l^− 1. When diatoms and ciliates were offered together C. hamatus (both sexes) fed exclusively on ciliates as long as they contributed with more than 5% to the mixture. This indicates the capability of active prey selection and switching between suspension feeding and ambush predation. Therefore, the feeding behaviour of adult C. hamatus can be characterised as omnivorous with a preference for larger motile prey. This implies a trophic level above two, if there is a sufficient abundance of protozoan food available.     

花尾胡椒鲷早期发育阶段的摄食与生长特性

１９９８年４～６月份在集美大学水产学院海水育苗试验场对人工培育的花尾胡椒鲷早期发育阶段的摄食和生长特性进行分析。结果表明,在水温为２５℃时,仔鱼约经６０～７０h 左右开口摄食,开口饵料为经１２０目筛网过滤的褶皱臂尾轮虫,以后随着鱼体的生长,依次投喂卤虫无节幼体和桡足类。对３７２尾仔、幼鱼解剖观察结果,摄食率达９７．０％,摄食量占体重的６．４％～２３．４％,日摄食量占休重的２４．８％～８３．７％,摄取     

海洋养殖鱼类仔稚鱼摄食和营养研究的进展

海洋鱼类人工育苗常出现仔稚鱼死亡率高的情况，它涉及到亲鱼培育、卵子质量、仔稚鱼营养需求、生物饵料供应和配合饲料取代等问题.本文就海洋鱼类仔稚鱼培育的饵料系列、亲鱼和早期发育中的脂类代谢和氨基酸作用、生物饵料的营养强化以及微粒、微囊饲料等研究进展作了概述.     

福建海区拥剑梭子蟹、红星梭子蟹和锈斑的食性与营养级研究

本文主要研究福建海区拥剑梭子蟹、红星梭子蟹和锈斑(虫寻)3种经济蟹类的食性与营养级.结果表明,3种蟹类胃饱满系数呈现明显的季节变化,拥剑梭子蟹、红星梭子蟹和锈斑(虫寻)胃饱满系数高峰分别出现在秋季、春季和冬季;3种蟹类皆为摄食混合饵料的动物,甲壳类和鱼类是它们的主要食物,其食性的生态类型较为接近,拥剑梭子蟹、红星梭子蟹属较典型的底栖生物食性类型,而锈斑(虫寻)的食性相对较杂.其混合饵料的营养级分别为2.38、2.59和2.60,均处于第三营养层次(低级肉食性动物).3种蟹类之间的食物的重叠指数均超过0.7,它们的食物重叠显著,对该海域的甲壳动物(主要是长尾类和短尾类)、鱼类、珊瑚虫、腹足类、底栖藻类等饵料资源存在激烈的竞争.     

花鲈仔、稚、幼鱼摄食习性与生长的研究

分析了花鲈仔、稚、幼鱼的摄食习性与生长.结果表明,在水温为15.5～16.5℃时,花妒仔鱼孵出约140h左右开口摄食,开口饵料为小型臂尾轮虫.全长10mm左右的仔鱼可摄食卤虫幼体,全长11mm左右的个体可摄食枝角类.对431尾仔、稚、幼鱼观察结果,在实验条件下其摄食率高达99.1%,胃饱满系数波动于2.38%～16.48%之间,日摄食指数在45%～60%.其摄食强度具明显的昼夜节律,以16:00～20:00胃饱满度最高.仔、稚鱼夜间基本不摄食,部分幼鱼个体少量摄食.仔、稚、幼鱼个体间生长速度具有一定的差异性.其体重与摄食量的关系符合直线方程y=0.1018+8.3261×10-2x;全长与体重的相关关系可用ω=1.6473×10-3L3.4743表示,全长与日龄的关系式为L_t=5.5242e1.9681×10-2D;体重与日龄的回归方程为ω=0.5836e6.9208×10-2D.     

花刺参幼参摄食和消化器官形态学和组织学研究

花刺参(Stichopus monotuberculatus)是中国热带海参中具有较高经济价值的可食用海参之一.本文以花刺参幼参为实验对象,主要研究其摄食器官触手的形态特征与消化器官肠道不同区段的组织结构.结果 显示,花刺参的口周围共有20个等长的触手,每个触手由柄部和楣状触手组成.檐状触手向外张开呈掌状,从掌心中央向...     

南黄海梭形纽鳃樽昼夜垂直移动的初步研究

本文对2006年12月、2007年5月和6月在南黄海两个连续站S1-4和S3-3采集的梭形纽鳃樽的昼夜垂直移动进行了研究。结果表明, 在不同季节不同海域该种昼夜垂直移动行为略有差异。在S1-4站位, 12月份梭形纽鳃樽复体从未到达底层(50—70m), 在0—50m的水层中表现出不规则的昼夜垂直移动。从中午(12:00)到傍晚(18:00)主要分布在表层, 之后移动到较深的水层(10—30m), 而单体由于数量较少而未进行昼夜垂直移动分析; 5、6月份, 该种单体和复体都出现了明显的反向昼夜垂直移动, 即白天迁移到表层, 夜间向底层迁移, 5月份尤为明显。在S3-3站位, 12月份和5月份梭形纽鳃樽的单体和复体几乎在整个水层都有分布。12月份梭形纽鳃樽复体在夜间有向下移动的趋势, 在06:00时到达最底层, 白天主要分布在20m以上的水层中。5月份梭形纽鳃樽单体和复体昼夜垂直移动不明显, 但主要分布在10—20m的水层中。     

Stomach contents of cetaceans incidentally caught along Mangalore and Chennai coasts of India

The stomachs of 32 individuals of seven cetacean species incidentally caught in gill net and purseseine fisheries along Mangalore and Chennai coasts (India) between 2004 and 2006 were examined. The whole stomach (fore-gut, mid-gut and hind-gut) was examined in all cases. Prey remains (666 prey items comprising six species of teleosts, one crustacean and one squid species) were found in the stomachs of eight individuals (the remaining 24 stomachs were found to be empty). All cetaceans were found to feed mostly on teleosts with wide range of trophic levels. Based on an index that included frequency of occurrence, percentage by number and by weight, the oil sardine Sardinella longiceps was the main prey in the sample. Cetaceans appear to favour both pelagic as well as demersal prey, possibly indicating surface and benthic feeding habits.     

Is feeding behaviour related to glass eel propensity to migrate?

Several studies have shown that eel diadromy is facultative and that migratory divergences may appear during glass eel estuarine migration. The origin of the differences in migratory behaviour among glass eels remains unclear but initial evidence supports the role of individual energetic and thyroidal status. Even if starvation is usually associated with glass eel migration, feeding does seem to occur in some glass eels. The aim of the present study was to investigate feeding behaviour and glass eel growth in relation to the propensity to migrate. Feeding rate and weight gain were higher in fish having a high propensity to migrate (M⁺ fish) than in fish having a low propensity to migrate (M⁻ fish) in fed glass eels, whereas no clear difference in the variation in body weight was observed among unfed fish (controls). M⁻ fish initially had lower percent dry weight than M⁺ fish, which suggests a link between appetite, propensity to migrate, and energy content. We discuss the role played by endocrine signals on these processes. In fish, thyroid hormones contribute to the control of growth and development. In addition, they play a role in flatfish and leptocephalus metamorphosis and appear to be involved in smolt and glass eel migratory behaviour. As such, they represent a good candidate which would promote the propensity to migrate as well as digestive system development. Their role in the hormonal control of food intake however remains vague.