长江江苏段浮游动物群落结构调查报告

2004年9月和12月、2005年3月对长江江苏段浮游动物的群落结构进行调查.浮游动物108种,以轮虫最多,45个种属,占41.66%;原生动物12个种属,占11.11%;枝角类25个种属,占23.14%;桡足类26个种属,占24.07%.年浮游动物密度为47.96个/L,生物量0.3663mg/L.全年常见的优势类群为:轮虫的臂尾轮虫属、三肢轮虫属、龟甲轮虫属、晶囊轮虫属;枝角类的象鼻溞属、秀体溞属;桡足类的真剑水蚤属、温剑水蚤属、许水蚤属.     

尤溪街面水库浮游甲壳动物的初步研究

2008年8月对尤溪街面水库的浮游甲壳动物进行了调查,共采集到浮游甲壳动物8科13属16种,其中枝角类5科7属8种,桡足类3科6属8种。枝角类优势种为突额湖仙达溞和长肢秀体溞,桡足类优势种为广布中剑水蚤。浮游甲壳动物平均密度为43.58ind/L,平均生物量为477.43μg/L。浮游甲壳动物种数由蓄水前的8种增加到16种,广布中剑水蚤和透明温剑水蚤在蓄水后仍然存在。     

珠江口浮游动物分布特征研究

为研究珠江口浮游动物的时空分布变化特征，于2006年至2007年间，对珠江河口区丰水期（8月份）、平水期（11月份）、枯水期（2月份）的浮游动物进行采样分析。共采集浮游动物94种，甲壳动物占绝对优势，共鉴定出49种，其中桡足类35种，枝角类14种；其次轮虫类有28种；原生动物6种；被囊动物和糠虾类各2种；多毛类、螺类、水母类和异足类各1种；还有3种未知种类。还发现浮游幼虫10类。珠江口浮游动物的优势种主要有河口半咸水种中华异水蚤（Acartiella sinensis）、指状许水蚤（Schmackeria inopinus）、中华窄腹剑水蚤（Limnoithona sinensis）、短角异剑水蚤（Apocyclops royi）和轮虫类萼花臂尾轮虫（Brachionus catyciflorus）、镰状臂尾轮虫（Brachionus falcatus）、前节晶囊轮虫（Asplanchna priodonta）以及枝角类长额象鼻溞（Bosmina longirostris）。这些优势种多为耐污种类，表明珠江口的水质已受到污染。依据珠江口不同水文期采样调查的物种多样性指数和均匀度指数，浮游动物多样性指数在2007年2月枯水期最低，2006年11月平水期最高。[中国水产科学，2008，15（2）：260-268]     

三道河水库浮游甲壳动物群落结构特征的初步研究

研究了湖北省三道河水库2007年8月至2008年4月浮游甲壳动物的群落结构及现存量的时空变化。三道河水库6个采样点(Ⅰ～Ⅵ)共鉴定出浮游甲壳动物8科、13属、21种,其中枝角类5科、9属、14种,优势种为简弧象鼻溞(Bosmina coregoni)、短尾秀体溞(Diaphanosoma brachyurum)和透明溞(Daphnia hyalin);桡足类3科、4属、7种,优势种为广布中剑水蚤(Microcyclops leuckarti)和汤匙华哲水蚤(Sinocalanus dorrii)。浮游甲壳动物年平均密度为92.6个/L,枝角类和桡足类分别为36.9个/L和55.7个/L;平均生物量为1.126mg/L,枝角类和桡足类分别为0.737mg/L和0.389mg/L。浮游甲壳动物现存量的季节变化明显,密度和生物量由高到低依次为秋季>夏季>冬季>春季。浮游甲壳动物密度的水平分布差异明显,采样点的密度和生物量由高到低为Ⅱ>Ⅵ>Ⅲ>Ⅰ>Ⅳ>Ⅴ。     

河南辖区丹江水库浮游生物调查报告之二——浮游动物

（二）浮游动物 1.浮游动物的种类组成及分布丹江库区的浮动物共检出52种(其中原生动物14种，以砂壳虫为优势种；轮虫计23种，以壶状臂尾轮虫，针簇多肢轮虫占优势；枝角类11种，以秀体藻，小栉蚤为优势；桡足类检索至目主要有镖水蚤，剑水蚤猛水蚤和无节幼体．桡足类在浮游动物中占有较大比重，见表6。     

温瑞塘河后生浮游动物群落结构及其与环境因子的关系

2011年1-7月对温瑞塘河后生浮游动物的群落结构及其栖息环境进行了调查,10个采样点共鉴定出后生浮游动物24种;其中,轮虫15种、枝角类6种、桡足类3种;优势种包括萼花臂尾轮虫(Brachionus calyciflorus)、壶状臂尾轮虫(B.urceus)、镰状臂尾轮虫(B.falcaty)、前节晶囊轮虫(Asplanchna priodonta)、长三肢轮虫(Filinia longiseta)、长足轮虫(Rataria neptunia)、指状许水蚤(Schmackeria inopinus)、广布中剑水蚤(Microcyclops leuckarti)和多刺裸腹溞(Moina macrocopa),优势种组成随季节变化略有不同;浮游动物的月均密度为13.39 ～310.8个/L,月均生物量为0.29 ～ 26.04 mg/L,两值均随水温的升高而增高;就空间分布状况看,浮游动物密度和生物量在各样点间存在明显差异.浮游动物与环境因子的典范对应分析(CCA)结果显示,温瑞塘河的水温是影响浮游动物密度变化最主要的因素(P≤0.05);而高锰酸钾指数( CODMn)、总氮(TN)和氨氮(NH4+)对浮游动物密度的分布也有重要影响,但总氮的变化趋势由NH4+的多少决定.建议在温瑞塘河水环境治理过程中,重点关注水体CODMn和NH4+的分布状况.     

尤溪街面水库浮游甲壳动物的初步研究

２００８年８月对尤溪街面水库的浮游甲壳动物进行了调查，共采集到浮游甲壳动物８科１３属１６种，其中枝角类５科７属８种，桡足类３科６属８种。枝角类优势种为突额湖仙达蟤和长肢秀体蟤，桡足类优势种为广布中剑水蚤。浮游甲壳动物平均密度为４３．５８ｉｎｄ／Ｌ，平均生物量为４７７．４３μｇ／Ｌ。浮游甲壳动物种数由蓄水前的８种增加到１６种，广布中剑水蚤和透明温剑水蚤在蓄水后仍然存在。     

沙颍河阜阳段浮游甲壳动物的群落结构与季节变化

从2011年4月至2012年1月,分季节在3个采样点对沙颍河阜阳段的浮游甲壳动物进行了调查。结果表明,沙颍河阜阳段共记录浮游甲壳动物20种,其中枝角类11种,桡足类9种;枝角类中各季节均为优势种的有蚤状溞(Daphnia pulex)和大型溞(D.magna);桡足类中各季节均为优势种的有近邻剑水蚤(Cyclops vicinus)和广布中剑水蚤(Mesocyclops leuckarti);浮游甲壳动物密度在春季(4月)最高,冬季(1月)最低。Shannon-Wiener多样性指数在1.30~2.13,初步评价表明沙颍河阜阳段水质处于轻度-中度污染状态。     

黄海北部春季和夏季浮游动物生态特性与时空分布

根据2015年3月(春季)和6月(夏季)对黄海北部辽宁近岸海域的浮游动物调查结果,分析了两个季节的浮游动物种类、生物量、丰度等群落结构特征。此次调查共鉴定出浮游动物47种,其中春季42种,夏季34种。浮游动物以浮游幼虫和小型桡足类为主。桡足类幼虫、棘皮动物幼体、桡足类幼体、洪氏纺锤水蚤、短角长腹剑水蚤、小拟哲水蚤、拟长腹剑水蚤和腹针胸刺水蚤为春季优势种;夏季浮游动物优势种依次为桡足类幼体、洪氏纺锤水蚤,拟长腹剑水蚤、短角长腹剑水蚤、桡足类幼虫、小拟哲水蚤和腹针胸刺水蚤。春季浮游动物平均生物量为512.09mg/m~3,平均丰度为15 522.18个/m~3;夏季浮游动物平均生物量为218.84mg/m~3,平均丰度为7582.39个/m~3;浮游动物生物量和丰度均为春季较高。黄海北部辽宁沿岸海域的浮游动物生物量、丰度较高。水温是影响浮游动物群落结构的重要环境因子。     

渫水河砷污染环境中浮游动物的群落特征研究

受高砷背景的影响,渫水河及其支流存在不同程度的砷污染,为揭示砷污染的生态效应,探寻防治对策,研究了该水域中浮游动物的种群分布和季节变化,分析其密度与砷含量及TN、TP的关系.2006-2007年共进行3次调查,设置8个采样断面;共检出浮游动物166种,其中,原生动物(95种)＞轮虫(55种)＞桡足类(10种)＞枝角类(6种);丰水期有104种,远大于平水期和枯水期.浮游动物现存量以丰水期最高,其次是平水期,枯水期最少;空间分布上以断面Ⅱ最高,黄水河支流高于渫水河干流,而渫水干流中段的现存量最小.种类组成上,由于桡足类和枝角类对重金属污染较为敏感,检出种类极少,且均是耐污型,轮虫则以α-β型种类为主,纤毛虫比例不高,只在断面Ⅱ和断面Ⅳ超过肉足虫比例.渫水河的Shannon-Wiener多样性指数、Simpson物种多样性指数、Margalef物种丰富度指数和Pielou均匀度指数值均＜2.生物多样性指数与As含量不相关(r=0.674),但轮虫密度与As含量显著相关(r=0.931).浮游动物密度与TN显著相关(r=0.826),TN对渫水河的浮游动物群落组成起着关键作用,而As只对轮虫的生物量影响较大,并不能决定整个浮游动物的群落结构.     

Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean

The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna.     

Protein and amino acid composition from the mantle of juvenile O ctopus vulgaris exposed to prolonged starvation

Protein and amino acid composition of the mantle of juvenile O ctopus vulgaris (Cuvier, 1797) during fasting for 27 days were determined. Average protein content of octopus mantle was of 711.19 ± 46.80 g kg^?1 DW, and it decreased with increasing fasting days. The non‐essential amino acids content was higher (486.18 ± 11.08 g kg^?1 protein) than essential amino acids (425.82 ± 9.15 g kg^?1 protein) at the start of the experiment (unstarved animals). The results suggest that the amino acid profile of the mantle where the most abundant amino acids are Arg, His, Lys, Gly, Leu and Pro could indicate a prolonged fasting condition (>20 days) or poor nutrition of O . vulgaris. This study supports the idea of using mantle for metabolic needs of starved O . vulgaris suggesting that the degradation pathway of amino acids to pyruvate and tricarboxylic acid cycle intermediates was favoured contrary to the degradation pathway of ketogenic amino acids. Special considerations should be taken concerning Thr, Ile, Ser, Ala, Asx (Asp, Asn), Glx (Glu, Gln) (because of their fast intake) and Lys and His (due to their stable contents) during a prolonged period of fasting.     

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.     

美人鱼发光杆菌对凡纳滨对虾非特异性 免疫功能及抗病力的影响

在基础饲料中分别添加0.1%和1%美人鱼发光杆菌灭活菌、0.1%美人鱼发光杆菌活菌配制成3种免疫实验饲料,以基础饲料为空白对照组饲料,每组设3个平行样。对个体质量为(4.83±0.36)g的凡纳滨对虾进行为期20 d的饲养实验,分别在0、5、10、15和20d进行取样,以血清中的酚氧化酶(PO)、酸性磷酸酶(ACP)、碱性磷酸酶(AKP)、超氧化物歧化酶(SOD)和溶菌酶(UL)活性为免疫指标,探讨了美人鱼发光杆菌作为免疫制剂对凡纳滨对虾非特异性免疫效应的影响;在投喂免疫饲料后的第22天,按0.004 2 kg/kg体重的剂量,直接投喂对虾白斑综合征病毒(WSSV)病料,并记录累积死亡率。结果表明,美人鱼发光杆菌免疫实验组对凡纳滨对虾血清中PO、ACP、AKP、UL和SOD活性影响明显高于对照组,并且在饲料中添加美人鱼发光杆菌后,明显提高了对虾抵御WSSV感染的能力。其中0.1%美人鱼发光杆菌活菌实验组的抗病毒感染能力最强,WSSV感染14d内累计死亡率为63.3%±5.8%;而对照组为96.7%±3.3%。研究表明,美人鱼发光杆菌添加在对虾饲料中能提高凡纳滨对虾非特异性免疫水平,增强抵抗疾病的能力,将其作为对虾免疫增强剂具有良好的应用前景。     

Effects of Spirulina platensis as a feed additive on growth and coloration of blue dolphin cichlids (Cyrtocara moorii Boulunger, 1902)

This study was carried out to investigate the effects of replacing fish meal with dietary Spirulina as a feed supplement on the growth performance and coloration of blue dolphin cichlids (Cyrtocara moorii). Five isonitrogenous (47% crude protein) and isocaloric (17.36 kJ/g digestible energy) diets were for formulated to replace FM with 0, 5, 10, 15 and 20% Spirulina (designated as Control, SP5, SP10, SP15 and SP20 respectively) and fed to the fish (initial body weight, 3.15 ± 0.01 g). Fish were randomly distributed into fifteen 120 L aquariums (26.5 ± 1.00°C), 15 fish per aquarium. The diets were tested in triplicate for 12 weeks. Experimental groups were fed twice daily (09:00 and 17:00) by hand to satiation. At the end of the feeding trial, significantly (p < 0.05) higher weight gain (WG), specific growth rate (SGR), protein efficiency ratio (PER) and lower feed conversion ratio (FCR) were observed in fish fed the SP10 diet when compared to the SP20 diet. There was no significant difference in these parameters between the other groups. The skin coloration of blue dolphin cichlid fed a diet containing Spirulina meal was enhanced. The best coloration was observed in the SP15 group. These impressions were objectively validated by chemical determinations of carotenoids extracted from fish skins and passed statistical tests of significance. The study findings show that Spirulina meal does not diminish growth rates except at very high levels.     

Dietary thiamin and pyridoxine requirements of fingerling Indian major carp,Cirrhinus mrigala (Hamilton)

Two experiments were conducted to quantify the dietary thiamin (experiment I) and pyridoxine (experiment II) requirements of fingerling Cirrhinus mrigala for 16 weeks. In experiment I, dietary thiamin requirement was determined by feeding seven casein–gelatin‐based diets (400 g kg^?1 CP; 18.69 kJ g^?1 GE) with graded levels of thiamin (0, 0.5, 1, 2, 4, 8 and 16 mg kg^?1 diet) to triplicate groups of fish (6.15 ± 0.37 cm; 1.89 ± 0.12 g). Fish fed diet with 2 mg kg^?1 thiamin had highest specific growth rate (SGR), protein retention (PR), RNA/DNA ratio, haemoglobin (Hb), haematocrit (Hct), RBCs and best feed conversion ratio (FCR). However, highest liver thiamin concentration was recorded in fish fed 4 mg thiamin kg^?1 diet. Broken‐line analysis of SGR, PR and liver thiamin concentrations exhibited the thiamin requirement in the range of 1.79–3.34 mg kg^?1 diet (0.096–0.179 μg thiamin kJ^?1 gross energy). In experiment II, six casein–gelatin‐based diets (400 g kg^?1 CP; 18.69 kJ g^?1 GE) containing graded levels of pyridoxine (0, 2, 4, 6, 8 and 10 mg kg^?1 diet) were fed to triplicate groups of fish (6.35 ± 0.37 cm; 1.97 ± 0.12 g). Fish fed diet containing 6 mg kg^?1 pyridoxine showed best SGR, FCR, PR, RNA/DNA ratio, Hb, Hct and RBCs, whereas maximum liver pyridoxine concentration was recorded in fish fed 8 mg kg^?1 dietary pyridoxine. Broken‐line analysis of SGR, PR and liver pyridoxine concentrations reflected the pyridoxine requirement from 5.63 to 8.61 mg kg^?1 diet. Data generated during this study would be useful in formulating thiamin‐ and pyridoxine‐balanced feeds for the intensive culture of this fish.     

Sea bream culture in Egypt; status, constraints and potential

Marine fish farming in Egypt began in 1976 with the culture of gilthead sea bream, (Sparus aurata) as this fish was notably adaptable to brackish and marine pond conditions. Today, marine fish and shrimp farms amount to about 19,000 ha, out of which 42% is already in production while the rest, i.e., 58% is still under construction. In 1997, cultured gilthead sea bream production of 2,250 tons made up 3% of the 75,000 tons total aquaculture catch. In polyculture, usually with the grey mullet and sea bass, gilthead sea bream contributed 440 kg ha^–1 to the total yield of 1,700 kg ha^–1 (26%) over a period of 16 months. For the same period, the yield of monoculture ponds averaged 100 kg ha^–1, while in marine cages, yields ranged from 4–10 kg m³. In 1996–1997, fry of 0.25–1 g and fingerlings 1–10 g with a total of 3 million, were collected from the wild and 1 million fry were produced in the three marine hatcheries out of the four existing ones. The development of sea bream culture in Egypt is now severely inhibited by the shortage of seeds and adequate feeds. Exports of both sea bream and sea bass, during 1994–1996 averaged 1,300 tons per year.     

A Minchinia mercenariae‐like parasite infects cockles Cerastoderma edule in Galicia (NW Spain)

The cockle Cerastoderma edule fishery has traditionally been the most important shellfish species in terms of biomass in Galicia (NW Spain). In the course of a survey of the histopathological conditions affecting this species in the Ria of Arousa, a haplosporidan parasite that had not been observed in Galicia was detected in one of the most productive cockle beds of Galicia. Uni‐ and binucleate cells and multinucleate plasmodia were observed in the connective tissue mainly in the digestive area, gills and gonad. The parasite showed low prevalence, and it was not associated with abnormal cockle mortality. Molecular identification showed that this parasite was closely related to the haplosporidan Minchinia mercenariae that had been reported infecting hard clams Mercenaria mercenaria from the Atlantic coast of the United States. The molecular characterization of its SSU rDNA region allowed obtaining a fragment of 1,796 bp showing 98% homology with M. mercenariae parasite. Phylogenetic analysis supported this identification as this parasite was clustered in the same clade as M. mercenariae from the United States and other M. mercenariae‐like sequences from the UK, with bootstrap value of 99%. The occurrence of M. mercenariae‐like parasites infecting molluscs outside the United States is confirmed.     

Involvement of gonadal steroids in final oocyte maturation of white perch (Morone americana) and white bass (M. chrysops): in vivo and in vitro studies

Plasma estradiol-17 (E₂), testosterone (T), 17,20-dihydroxy-4-pregnen-3-one (DHP) and 17,20,21-tri-hydroxy-4-pregnen-3-one (20-S) levels were measured by radioimmunoassay (RIA) in white perch (Morone americana) and white bass (M. chrysops) that were induced to undergo final oocyte maturation (FOM) with human chorionic gonadotropin (hCG). Plasma DHP levels increased in females of both species in association with oocyte germinal vesicle migration (GVM) and germinal vesicle breakdown (GVBD) and decreased thereafter. Plasma 20-S levels also increased with oocyte GVM in white bass, but were several-fold lower than DHP levels. Circulating E₂ and T levels were greatest during GVM and GVBD in both species and decreased to low levels during oocyte hydration and ovulation. Follicles from white perch and white bass which received a priming injection of hCG in vivo, produced both DHP and 20-S in vitro after exposure to hCG and their oocytes underwent GVBD. Ovarian incubates from unprimed fish of either species produced only E₂ and T and their oocytes did not complete GVBD. Oocytes from unprimed bass, but not perch, matured when follicles were exposed to hCG in vitro. Both trilostane and cycloheximide blocked in vitro production of DHP and 20-S and oocyte GVBD by white perch follices. DHP and 20-S were equipotent inducers of FOM in the GVBD bioassay. None of several other structurally-related steroids tested were effective within a physiological range of concentrations. These results indicate a role for DHP and 20-S in the control of FOM in white perch and white bass.