黄颡鱼早期发育阶段摄食的研究

本实验采用实验生态学的方法，分别对池养9、13、17、23日龄黄颡鱼的食物组成，选食行为和昼夜摄食节律进行了研究。结果表明，黄颡鱼早期发育阶段主要摄食浮游动物，其食物组成随仔稚鱼的生长而变化。摄食初期（黄颡鱼9日龄时）主要食物为枝角类和轮虫，其中枝角类数量和重量百分比分别为86.71%和89.65%，占绝对优势。之后，黄颡鱼的摄食范围进一步扩大，从23日龄开始，由主要选食枝角类转为主要选食桡足类，桡足类所占数量百分比也从初期的3.29%上升到23日龄时的26.68%；而且，从13日龄开始，摇蚊幼虫等底栖动物所占比重呈上升趋势，从初期的54.84%到23日龄的69.52%，始终在食物组成中占主要优势。黄颡鱼摄食具有明显的昼夜节律性，9日龄时摄食高峰值出现在20:00（897.7），低峰值出现在19:00（161.8）；13、17、23日龄仔稚鱼胃平均饱满指数均于4:00达最高峰（914.1、1113.1和199.7），于19:00、19:00和16:00达最低值，分别为50.9、60.9和76.6，夜间时段摄食水平显著高于白天时段，黄颡鱼仔稚鱼明显表现为晚上摄食类型。     

梁子湖6种凶猛鱼饵料相似性研究

对梁子湖6种凶猛鱼间的铒料相似性作了研究。以铒料组成的更正重量百分比为基础,计算营养位宽度、营养位重叠指数及食物重叠指数。结果表明：红鳍原Bo、青梢Bo、翘嘴Bo3种间及鳜、鲇、黄颡鱼间的铒料相似程度较高。依据食物重叠指数进行聚类分析,可以把6种凶猛鱼类划分为2个类型,红鳍原Bo、青梢Bo、翘嘴Bo属中上层摄食类型,鳜、鲇、黄颡鱼属中下层摄食类型。     

渤海日本鲟和三疣梭子蟹食性的研究

运用出现频率（F％）、尾数百分比（N％）、食物重叠指数（P）以及生境宽度（B）等指标分析了渤海日本和三疣梭子蟹的食性。结果表明，日本和三疣梭子蟹都属于底栖动物食性。主要饵料包括双壳类、底栖甲壳类、鱼类和头足类。日本碍食物生境宽度高于三疣梭子蟹。二者在各季节的食物重叠指数波动在0．39～0．53之间，属于中等重叠水平。摄食率都比较高，多在90％以上。     

东海蓝圆鲹的摄食习性

以2008年5月至2009年2月东海灯光围网采集到的叉长范围为52～276 mm的444尾蓝圆鲹为对象,对其胃含物进行分析,应用K-W非参数检验、卡方检验、聚类分析等方法,对不同季节和发育阶段条件下蓝圆鲹的食性进行了研究。结果表明,蓝圆鲹的摄食种类有80余种,浮游甲壳类(主要包括浮游甲壳类幼体、磷虾和桡足类等)和小型鱼类为其主要食物类群。若按相对重要性指数百分比(IRI%)排序,优势饵料种类最高的是七星底灯鱼(IRI%为40.44%),其次是口虾蛄Alima幼体(IRI%为14.24%)、太平洋磷虾(IRI%为11.26%)等。统计分析检验表明,蓝圆鲹的空胃率和平均胃饱满系数有显著的季节变化和叉长变化(P<0.01),摄食强度春季最高,秋季和夏季相对较高,而冬季最低;叉长50～99 mm和200～299mm的蓝圆鲹的摄食强度较高,其余叉长的强度相对较低。食物组成也随季节和发育阶段的不同而有所变化,在春季主要以七星底灯鱼和口虾蛄Alima幼体为食,夏季主要以甲壳类幼体为食,秋季主要以七星底灯鱼和太平洋磷虾为主食,冬季食物匮乏,小型桡足类丽隆剑水蚤和糠虾类占其食物组成的很大比例。聚类分析的结果表明,蓝圆鲹叉长200 mm是其摄食取向的拐点,小于这个叉长的蓝圆鲹以浮游甲壳类为主,大于这个叉长的以捕食小型鱼类为主,随着叉长的增大,蓝圆鲹更多的以游泳动物为食。根据蓝圆鲹摄食饵料的类群变化,东海蓝圆鲹的营养级为3.55,属于浮游动物和游泳动物混合食性的肉食性鱼类。     

长江口外海域龙头鱼营养生态学特征

利用2009年9月至2010年8月在东海北部、黄海南部海域获取的龙头鱼(Harpadon nehereus)样品,采用胃含物分析法,对龙头鱼的摄食习性进行了研究。结果表明,龙头鱼摄食饵料种类有39种,鱼类是其主要饵料类群,所占质量百分比为84.13%。优势饵料种类为龙头鱼(Harpadon nehereus)、小黄鱼(Pseudosciaena polyactis)、细条天竺鱼(Apogonichthys lineatus)、皮氏叫姑鱼(Johnius belengerii)、口虾蛄(Oratosquilla oratoria)等。龙头鱼的摄食强度秋季最高,冬季最低;食物组成季节变化明显,春季主要摄食虾类,其他季节则主要以鱼类为食;不同生长发育阶段的食物组成及摄食强度具有显著差异,体长为100 mm和250 mm处存在食性转换现象,并在体长250 mm时表现为由广食性向狭食性转换的特征,摄食选择性增强。龙头鱼营养级为3.80,在东、黄海食物网中处于较高的营养层次。     

水温对黄颡鱼摄食的影响

本实验在不同温度下对黄颡鱼的摄食情况进行了观察。结果表明 :黄颡鱼在人工养殖条件下 ,水温对其摄食具有显著的影响。开始摄食水温为 11℃ ;较低温度下 ,黄颡鱼摄食率随温度升高而升高 ;当温度上升达到 2 9℃时 ,黄颡鱼摄食率随温度升高而下降。黄颡鱼的最适摄食率温度为 2 5～ 2 8℃ ,摄食率为 4 0 6～ 4 36 %。试验温度2 6℃时 ,获得最大摄食率 4 36 %。     

黄颡鱼养殖技术之三 江黄颡、鳜鱼、青虾混养技术

江黄颡鱼 Pseudobagrusvachelli (Richardson)又称瓦氏黄颡鱼,属鲶形目、鱼危科、黄颡鱼属,是该属中个体最大的种类,目前发现的最大个体体重为1750g,自然分布与长江、淮河、珠江及其干流中,为底栖经济鱼类,是我国的传统渔业对象之一。江黄颡鱼为偏动物性的杂食性,鳜鱼为凶猛肉食性,喜摄食活鱼、活虾,青虾为杂食性,三者中,江黄颡和鳜鱼都喜食鱼虾,但鳜鱼只捕食活鱼和活虾,江黄颡则更多的摄食死鱼和死虾,因此,江黄颡与鳜鱼之间没有食性冲突,投喂饵料鱼虾,两者各取所需。江黄颡、青虾都摄食配合饲料,但江黄颡主要摄食颗粒饲料,青虾则主要摄食…     

渤海日本Xun和三疣梭子蟹食性的研究

运用出现频率（Ｆ％），尾数百分比（Ｎ％），食物重叠指数（Ｐ）以及生境宽度（Ｂ）等指标分析了渤海日本Ｘｕｎ和三疣梭子蟹的食性，结果表明，日本Ｘｕｎ和三疣梭子蟹都属于底村动物食性，主要饵料包括双壳类，底栖甲壳类，鱼类和头足类，日本Ｘｕｎ食物生境宽度高于三疣梭子蟹。二者在各季节的食物重叠指数波动在０．３９～０．５３之间，属于中等重叠水平，摄食率都比较高，多在９０％以上。     

印度洋中西部水域黄鳍金枪鱼的食性及其季节性变化

根据2003年12月至2004年6月及2005年9月至12月在印度洋中西部水域调查所获得的数据,利用两因子列联表及单因子方差分析等统计分析方法,对印度洋中西部水域黄鳍金枪鱼的食物组成及其随月份和体长的变化、摄食强度及食物组成的生态位宽度进行了初步研究.结果表明,印度洋中西部水域黄鳍金枪鱼食物组成包括帆蜥、鲣、鳞鲍、沙丁鱼、鲐鱼、虾、蟹、鱿鱼、章鱼、竹笑鱼及未辨认甲壳类等饵料类群,其中主要食物为鱿鱼、鲐鱼以及蟹.大部分月份黄鳍金枪鱼摄食率相对较高,基本上维持在70%以上;除2月和6月外,其余月份黄鳍金枪鱼饵料种类数更替率均低于50%.各叉长组黄鳍金枪鱼摄食率基本维持在70%以上;当叉长在106～155 cm之间,饵料种类数更替率低于40%.黄鳍金枪鱼摄食强度各月差异显著,但各叉长组摄食强度并不存在显著性差异.各月饱满指数存在显著性差异.黄鳍金枪鱼的食物组成随月份和叉长有明显变化.鱿鱼、鲐鱼和蟹基本上为不同叉长组黄鳍金枪鱼所摄食.黄鳍金枪鱼食物组成各月Shannon-Weiner多样性指数H'波动较大,且存在显著性差异;Pielou均匀度指数J'基本上维持在0.80～1.00之间,但各月间存在显著性差异.印度洋中西部水域黄鳍金枪鱼各叉长组食物组成Shannon-Weiner多样性指数H'变化较大,但在106～145 cm期间相对保持稳定,而Pielou均匀度指数J'波动较大.印度洋中西部黄鳍金枪鱼食物组成各月和各叉长组均存在显著性差异.     

精氨酸和赖氨酸对瓦氏黄颡鱼幼鱼生长和非特异性免疫力的影响

以初始体质量(2.12±0.01) g的瓦氏黄颡鱼为研究对象,在室内流水系统中进行为期56 d的摄食生长实验,探讨饲料中精氨酸、赖氨酸水平及其交互作用对瓦氏黄颡鱼幼鱼生长和非特异性免疫力的影响。采用3×3双因子实验设计,制作9种Arg和 Lys不同配比的饲料(粗蛋白42%、粗脂肪10%),其中Arg水平为2.41%、4.86%和6.81%(饲料蛋白),在每个Arg水平分别设1.95%、5.84%和8.27%(饲料蛋白)3个Lys水平。每种饲料随机投喂3桶(养殖桶规格:40 L),每桶30尾实验鱼。实验结果表明,饲料中Arg、Lys水平对瓦氏黄颡鱼生长和头肾巨噬细胞呼吸爆发活性均有显著影响(P<0.05),当Arg/Lys为6.81/5.84(饲料蛋白)时,实验鱼生长最佳,而头肾巨噬细胞活性最高值出现在 Arg/Lys 为4.86/8.27(饲料蛋白)水平。饲料中Arg水平对瓦氏黄颡鱼血清一氧化氮合酶(NOS)活性有显著影响(P<0.05),且在适中和高Arg水平时,血清NOS活性均高于低水平Arg组。饲料中Arg、Lys水平对血清精氨酸酶(ARG)活性和过氧化氢酶(CAT)活性无显著影响(P>0.05)。饲料中Arg和Lys对瓦氏黄颡鱼的生长存在交互作用,而对体组成、肝指数、头肾巨噬细胞呼吸爆发活性、血清中NOS、ARG和CAT活性均无交互作用。     

Natural diet of grapsoid crab <Emphasis Type="Italic">Plagusia dentipes</Emphasis> de Haan (Decapoda: Brachyura: Plagusiidae) in Tateyama Bay,Japan

The natural diet of Plagusia dentipes de Haan was studied in Tateyama Bay, Japan, between June 2004 and May 2005. A total of 389 specimens were collected for analysis of stomach content during the period, with sizes ranging between 7.1 and 63.1 mm in carapace width. The major dietary item was rhodophycean algae (mostly articulated coralline algae), which was ingested by 91.8% of the crabs and accounted on average for 55.6% (points) of the volume of stomach contents. Chlorophycean algae (mostly Ulvaceae, 39.1% and 8.1 points) and crustaceans (mostly amphipods, 38% and 3 points) came next in feeding frequency and volume. Minor dietary items also included other algae such as Phaeophyceae and animals such as mollusks (bivalves, gastropods), annelids (polychaetes), other crustaceans (caprellids, isopods), and echinoids. Significant seasonal dietary differences were observed and, in general, the diet in spring contained more food items, particularly more animals, compared to other seasons. Feeding of Rhodophyceae was highest and lowest in winter and summer, respectively. The total volume of food consumed was also lowest in summer and likely reflected reduced availability of the main food item in this season. There were no differences in dietary items between male and female crabs. In conclusion. P. dentipes is a primarily herbivorous crab with incidental or opportunistic feeding on animal items, and it is suggested that seasonal shifts in consumption may be related to growth, molting, and reproductive activity.     

枸杞岛海藻场大型底栖无脊椎动物摄食类群研究

随着海洋生态学研究的深入和海洋环境监测的需要,一些传统的研究方法如多样性指数等在评价大型底栖生物群落结构变化时显得说服力不足,而摄食功能群的研究越来越受到重视。本实验根据2012年8月对浙江枸杞岛海藻场大型底栖无脊椎动物的调查实验,分析该海域夏季大型底栖无脊椎动物摄食类群的组成、空间及数量分布,并进行相关生态评价。结果表明,枸杞岛海藻场夏季大型底栖无脊椎动物组成以肉食者和滤食者占较大优势,食碎屑者、植食者和食底泥者次之,杂食者最少;肉食者的优势种为布尔小笔螺、寄居蟹、扁平管帽螺、甲虫螺和四齿矶蟹等,滤食者的优势种为条纹隔贻贝、带偏顶蛤、短石蛏和布氏蚶等,植食者的优势种为钩虾、单一丽口螺和锈凹螺等;各摄食类群水平分布较均匀,垂直分布受水深和摄食饵料的限制;基于大型底栖无脊椎动物功能类群的生态参数评价结果表明,枸杞岛海藻场大型底栖无脊椎动物群落健康状态呈虚弱水平,大部分站位大型底栖无脊椎动物群落受到轻度扰动,底栖生态质量状况较好。     

Effects of feeding frequency on the growth of young estuary grouper, Epinephelus tauvina (Forskål), cultured in floating net-cages

Studies on the effects of feeding frequency on the growth of young estuary groupers (Epinephelus tauvina) with initial size ranging from 16.2 to 16.9 cm in total length were conducted in floating net-cages. Seven feeding frequencies in the order of one feeding in 5 days, 4 days, 3 days, 2 days, 1 day, two feedings daily and three feedings daily were studied. Optimal growth and good food conversion ratio as well as higher survival rate were obtained in groups fed to satiation with one feeding in 2 days. Weight gains were substantially reduced in groups fed to satiation with one feeding in 5, 4 or 3 days and were not enhanced when the feeding frequencies were increased to two or three feedings daily. The fact that food conversion ratios were similar in fish fed to satiation with one feeding in 5, 4, 3 and 2 days suggests food intake to be important as a growth limiting factor. Total food intake per feeding was appreciably higher in fish fed once in 2 days. The intake of food was found to be closely related to the amount of food remaining in the stomach, intake being maximal when the stomach was empty. The food deprivation time in estuary groupers was found to be about 36 hours at which over 95% of the food was digested and less than 0.5% body weight of food remained in the stomach. Hence, feeding the fish at 48-hour intervals, i.e. once in 2 days, greatly enhanced maximum intake and efficient utilization of the food.     

海州湾大泷六线鱼摄食生态研究

根据2011年3—12月在海州湾及其邻近海域进行的5个航次底拖网调查,通过分析531尾大泷六线鱼(Hexagrammos otakii)的胃含物样品,对其摄食生态进行了初步研究。结果表明,大泷六线鱼摄食的饵料种类有60余种,虾类、蟹类、双壳类是其最主要的3种饵料类群,优势饵料生物有东方缝栖蛤(Hiatella orientalis)、疣背宽额虾(Latreutes planirostris)和钩虾(Gammarus sp.)等;其食物组成存在明显的季节变化和体长变化,全年均大量摄食虾类,夏季还摄食一定量的蟹类,秋季摄食多毛类和头足类的比例较高。随着体长的增长,大泷六线鱼摄食的饵料生物由小型甲壳类逐渐转变为体型较大的虾类和鱼类。大泷六线鱼的空胃率和平均胃饱满指数存在明显的季节变化,春季空胃率最高,冬季空胃率最低;平均胃饱满指数春季最高,秋季最低。典范对应分析表明,体长是影响大泷六线鱼摄食的主要因子,其次是底层水温、叶绿素a和pH。     

斑点叉尾对全植物蛋白饲料的胃排空及消化道内容物特性研究

为研究斑点叉尾(鱼回)[体质量(115.55±7.54)g]对全植物蛋白饲料的胃排空,实验比较了3种常用数学模型对其排空曲线的拟合程度,同时探究了摄食过程中消化道内容物的水分、pH和消化酶的变化规律.结果发现,3种数学模型均可较好地描述斑点叉尾(鱼回)胃排空曲线,平方根模型最适于定量描述,指数模型次之,线性模型较差.根据平方根模型分别计算得到斑点叉尾(鱼回)胃50％排空时间为12.8 h(以干重计),完全排空约36 h.在摄食后0～36 h内,内容物水分含量在后肠保持不变,在胃部呈缓慢上升趋势,而在前肠和中肠则呈先上升后下降趋势.消化道各段内容物pH在摄食后3h内均显著下降,3～30 h间总体保持平稳状态,在30 h后又呈显著上升趋势.消化道各段蛋白酶、脂肪酶和淀粉酶比活力在摄食3h内显著上升,并在3～30 h内保持相对稳定水平,摄食30 h后呈显著下降趋势.整个摄食过程中,消化道各段消化酶比活力大小依次为前肠＞中肠＞后肠＞胃.研究表明,斑点叉尾(鱼回)在摄食过程中,消化道各段内容物的水分、pH和消化酶比活力均随时间呈现相应的规律性变化.而这些内环境参数的相互作用,综合影响了特定胃排空时间的形成.     

Feeding Levels of the Southern Brown Shrimp Penaeus subtilis in Response to Food Dispersal

The development of efficient feed management strategies in shrimp farming involves the investigation of aspects related to time of feed distribution, feeding rates, feeding frequency, and feed dispersal methods. This work examined the feeding levels of Penaeus subtilis in response to food dispersal method under semi-intensive culture conditions. The study consisted of two treatments: 1) a uniform feed dispersal over the culture area, and 2) concentration of feed in 0.2-m² circular feeding trays. For each, three 105-m² rectangular enclosures were installed in a single shrimp grow-out pond and stocked with P. subtilis at a density of 14.29 postlarvae/m². Shrimp were fed daily at 0600, 0930 and 1430 h and sampled 30 min after feed distribution at 12-d intervals. After collection, shrimp weight was determined, their stomachs dissected and weighed. A total of 2,160 stomachs of P. subtilis were collected during a 89-d rearing cycle. Relative occurrence of artificial versus natural food in stomach contents was determined by stable carbon isotope mass spectrometry. Density of polychaetes in the substrate was monitored at each sampling period. After harvest, sediment samples were collected for physical and chemical analyses. In general, differences in shrimp growth between feeding methods were not significant. Final shrimp survival rates were between 69.0 ± 6.9% and 71.9 ± 3.7%. Stomach content weight of P. subtilis was significantly higher when feed was broadcast than for feed concentration. Average stomach content weight remained constant throughout the rearing cycle, although progressive increases in feed Occurrence were detected in P. subtilis diet. No periodicity in food intake along sampling periods could be related to increases in shrimp carapace length. Food intake was significantly lower at 0600 h than at 1430 h and at 0930 h, respectively. In both treatments, over half of the food contained in the stomach contents of shrimp was derived from artificial food. Sediment chemical analysis indicated statistically lower levels of sodium in the pond bottom of concentrated treatment. However, no short-term detrimental effects were detected on sediment chemical quality. Results indicated that feed broadcasting resulted in a greater access and a higher consumption of food among the cultured shrimp population, a lower number of empty stomachs, and a greater occurrence of artificial food in P. subtilis stomach contents.     

Food and feeding habit of taiwan mauxia shrimp <Emphasis Type="Italic">Acetes intermedius</Emphasis> in the coastal waters of Southwestern Taiwan

The stomach contents and feeding habits of the Taiwan mauxia shrimp Acetes intermedius were examined based on 420 specimens collected in the costal waters of south-western Taiwan. Two 24-h periodic samplings of specimens were completed to describe the diel feeding periodicity of this species. Phytoplankton was the main food for the Taiwan mauxia shrimp, and the dinoflagellates was the most important food. They also fed on zooplankton and amorphous materials. Their diet changed with the seasons. The feeding activity of this species mainly occurred at night. The results obtained in this study supported the hypothesis that A. intermedius performs a nocturnal vertical migration to avoid predators and to allow for safe feeding.     

Feeding strategy of the non‐native rainbow trout,Oncorhynchus mykiss,in low‐order Patagonian streams

The dietary composition and feeding strategy of rainbow trout, Oncorhynchus mykiss (Walbaum), in two low‐order Patagonian streams were studied. Benthic macroinvertebrate availability was estimated in both riffles and pools. Fish stomach contents were examined to determine prey richness and diversity, prey electivity, food‐niche width, and the feeding strategy employed by trout throughout the year. Availability of benthos varied seasonally with Ephemeroptera, Trichoptera, Plecoptera and Diptera species dominating. Rainbow trout diet was composed mainly of benthic macroinvertebrates, followed by terrestrial insects, fish, algae and plants. Different trout size classes segregated the use of food resources to reduce predation pressure. Elected prey included organisms displaying no to high mobility. A high feeding plasticity allows trout to buffer changes in food availability by switching from a specialised to a generalised feeding behaviour. Consequently, trout may exploit abundant but temporary food resources opportunistically, which would explain their marked expansion in Patagonian environments.     

Prey selectivity in planktivorous juvenile fishes associated with floating objects in the western Mediterranean

Aspects of the feeding ecology of planktivorous juvenile fishes were assessed by comparing stomach content samples from purse seine catches with food environment samples from vertical hauls of a WP-2 mesozooplankton net. Sampling was performed fortnightly over 2 years, around moored experimental floating objects and at open water control stations in oceanic Mediterranean waters. Species composition, abundance and seasonal occurrence of both potential prey (zooplankton) and predators (fish) were studied. Dietary composition was examined for six fish species, and prey selectivity was assessed by means of several selectivity indices: Ivlev's selectivity index, linear food selection index and forage ratio. A comparison of the results showed significant variations among indices, related to both the degree of selection and the relative abundance of the food type in the environment. Most fish caught were pelagic juveniles, and had fed on plankton; however, there was variability in diet composition and prey selectivity among species allowing their separation into generalists and specialists. The pilot fish Naucrates ductor (Linnaeus) was a specialist, preying upon neustonic hyperiid amphipods, whereas the three congeneric species of Trachurus: T. picturatus (Bowdich), T. trachurus (Linnaeus) and T. mediterraneus (Steinachner) fed on copepods and other planktonic crustaceans. The species studied appeared to partition food resources to minimize the overlap in use of a very specific habitat.     

东方对虾（Penaeus orientalis）在长江口外海区的索饵特性研究

东方对虾（Ｐｅｎａｅｕｓｕｓｏｒｉｅｎｔａｌｉｓ）是分布在我国黄渤海及东海北部的重要经济虾类。长江口海区（１６９渔场）受淡水迳流的影响，浮游生物及底栖动物的生物量较高，构成了对虾良好的索饵、肥育、越冬场所。本研究通过周年样品采集（共２１６尾），逐尾进行个体测量和胃含物观察分析，查明了东方对虾在该海区的食物组成和摄食强度季节变化。其食物组成有８大类：硅藻类、原生动物、海绵动物、环节动物、软体动物、甲壳动物、棘皮动物及鱼类。摄食强度以春夏季和秋季为高，但冬季也摄食。在不同的水域（沿岸、近海）和环境（大潮、小潮）下有不同的食物组成，表明东方对虾的食性相当广泛。