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1.
In order to clarify whether the planktivorous silver carp and bighead carp can collect phytoplankton as small asCyclotella(<20 μm) in Donghu Lake, studies on phytoplankton in their gut contents and feces were made in 1990. The fish were cultured
in both net cage in Donghu Lake and aquaria with the lake water. Past the intestine, the average valve diameter ofCyclotella changed little. The average ratio of empty frustule ofCyclotella to totalCyclotella in the foregut contents of the fishes were 1.8–1.9 times higher than that in the lake water, but changed little from foregut
to feces. The aquarium experiment showed that both carps could collect particles as small as 8–10 μm, which was obviously
narrower than the distance between their gill rakers. Probably, secretion of mucus plays an important role in collecting such
small particles. 相似文献
2.
EXPERIMENTAL STUDIES ON THE ROLE OF PLANKTIVOROUS FISHES IN THE ELIMINATION OF MICROCYSTIS BLOOM FROM DONGHU LAKE USING ENCLOSURE METHOD 总被引：11，自引：0，他引：11
谢平 《中国海洋湖沼学报》1996,(3)
The hypertrophic subtropic Donghu Lake's dense water bloom(of mainly Microcystis Anaabaena andOscillatoria)that occurred annually from the beginning of the 1970s, has disappeared since 1985. The infiuenceof planktivorous fishes (silver and bighead carps) on the water bloom was studied for three years usingthe enclosure method. The enclosures stocked densely with bighead and/or silver carp were free of waterbloom during the experimental period. The water bloom that appeared in the fish-free enclosures was completelyeliminated in 10-20 days by introduction of silver and/or bighead carp(grass carp was not effectivein controlling water bloom).This study showed clearly that grazing pressure by planktivorous fishes is a keyfactor in eliminating water bloom from the lake. 相似文献
3.
Xie Ping 《中国海洋湖沼学报》1996,14(3):193-204
The hypertrophic subtropic Donghu Lake's dense water bloom (of mainlyMicrocystis, Anabaena andOscillatoria) that occurred annually from the beginning of the 1970s, has disappeared since 1985. The influence of planktivorous fishes
(silver and bighead carps) on the water bloom was studied for three years using the enclosure method. The enclosures stocked
densely with bighead and/or silver carp were free of water bloom during the experimental period. The water bloom that appeared
in the fish-free enclosures was completely eliminated in 10–20 days by introduction of silver and/or bighead carp(grass carp
was not effective in controlling water bloom). This study showed clearly that grazing pressure by planktivorous fishes is
a key factor in eliminating water bloom from the lake.
This work was supported by FEBL (State Key Laboratory for Freshwater Ecology and Biotechnology of China) funds and by the
National Natural Science Foundation of China (Grant No., 3937014). 相似文献
4.
ImODUonONGrowingconcemovertheprobboofobnoxiouswaterbloornspromPtedagreatdealofresearchintothebiologyofblue-grmalgae(Reynolds&Walsby,l975,Reynothe,l984).PreviousstudiesonMimptiSwereaimedatitSphySinlogicalcharaCteristirsindudinggroWthandbuoyancyraegnolds,l975),0Vendteringandphotosynthesisfea-turesffokamuraetal.,l984,Takamura,l985),nutrientdemandsoprlofTetal.,l952,0kado&Sudo,l979).TherearerepoffethatMicropstiswasawidelydistributalspedesthatcouldeasilybloomWhenambientenvironrnentSweresuit… 相似文献
5.
TheMicrocystis bloom that once disappeared from Donghu Lake, a shallow, eutrophic Chinese lake, was successfully resumed with the use of
the enclosure method. Seston and dissolved organic carbon (DOC) dynamics during theMicrocystis bloom were investigated with particular emphasis on the effect of three Chinese domestic fishes (silver carp, bighead carp
and grass carp). The results showed that the change of chlorophyll a obviously related to the fish species and its stocking
density. Due to the release of extracellular ogranic carbon and increased bacterial activity, DOC increased apparently after
silver and bighead carps were introduced. POC/DOC dropped considerably in the enclosures containing silver and bighead carps
and in the surrounding lake water, which implied that the bacterial activity was more pronounced in such ecosystems. Statistical
analysis indicated that the linear relationship between POC and chlorophyll a could reflect the state of algal growth and
nutrient metabolism. It was expected that this study would provide some information on biomanipulation in the shallow, eutrophic
lakes.
This work was supported in part by a Grant-In-Aid from the Chinese Academy of Sciences, State Key Laboratory of Freshwater
Ecology and Biotechnology (FEBL) affiliated to the Institute of Hydrobiology for the project “Control Ecosystem: An Approach
to Lake Restoration”. 相似文献
6.
《中国海洋湖沼学报》2021,(5)
Although intestinal fungi play important roles in host health and disease,the composition and diversity of fungal communities remain poorly reported in fish.In this study,fungi in the fore-,mid-,and hindintestine of tilapia(Oreochromis mossambicus) and bighead carp(Aristichthys nobilis) from Hongchaojiang Reservoir in Guangxi,China were investigated by ITS sequencing.Based on this,we obtained 1 763 478 high-quality tags,which clustered into 1 089 operational taxonomic units(OTUs).In total,404 OTUs were annotated,of which 310,68,and 26 belonged to Ascomycota,Basidiomycota,and other,respectively.Results show significant differences in the community composition of intestinal fungi between tilapia and bighead carp but not within their different intestinal segments.Furthermore,154 of the 404 annotated OTUs were considered reliable and were classified into three trophic modes and nine guilds.The three trophic modes consisted of 108 OTUs of saprotrophic fungi,41 OTUs of pathotrophic fungi,and five OTUs of symbiotrophic fungi.The top three most abundant OTUs overall(i.e.,Otu000002,Scopulariopsis acremonium; Otu000018,Alternaria palandui; Otu000034,Aureobasidium pullulans) showed lower abundance in the hind-intestinal segments of bighead carp,suggesting uneven distribution of these fungi in this species.In addition,saprotrophic and pathotrophic fungi were markedly decreased in the hindintestine.It is indicated that the fungal community was not only related to host species specificity but also to the respective physiological functions of different intestinal segments.These findings provide valuable information on the composition,structure,and potential function of the intestinal fungi community associated with different intestinal segments in tilapia and bighead carp under natural conditions,thus highlighting the importance of fungi as an integral part of the inte stinal microbiota in maintaining host health. 相似文献
7.
1 INTRODUCTION Surface blooms of nuisance cyanobacteria are often a signal of eutrophication (Jacoby et al., 2000). They are generally favored by conditions of low nitrogen to phosphorus ratios, high total phosphorus content, high water temperature, high … 相似文献
8.
《中国海洋湖沼学报》2017,(3)
Silver carp is one of the most important planktivorous fish in Chinese aquaculture and plays a significant role controlling cyanobacterial blooms. A balanced gut microbiota is crucial for growth and health of the host because of its important roles in immune defense, digestion of complex carbohydrates, and production of enterocytes. In our study, the dominant bacterial and cellulolytic bacterial( Clostridium I, Clostridium III, Clostridium XIVab, and Fibrobacter) communities in the contents and mucus of the silver carp gut(foregut, midgut, and hindgut) were analyzed by denaturing gradient gel electrophoresis and quantitative polymerase chain reaction(q PCR) analyses. The results revealed that the dominant and cellulolytic bacterial communities were significantly different among gut regions as well as in contents and mucus. Bacterial diversity and richness in contents and mucus increased along the gut and were higher in contents than those in local mucus. A sequence analysis of gut samples exhibited the conservative phylotypes of Proteobacteria, Actinobacteria, and Firmicutes. The gut of silver carp harbored an abundance of cellulolytic bacteria, particularly Clostridium XIV ab. The foregut segment had the highest proportions of the four cellulolytic bacteria, followed by the midgut and hindgut. However, the proportions of cellulolytic species in the silver carp gut was much lower than those in the terrestrial vertebrate gastrointestinal tract. We conclude that gut bacteria could help silver carp obtain energy from cyanobacteria, which may be why silver carp can maintain high growth rates during cyanobacterial blooms. 相似文献
9.
We report the genetic linkage map of Jian carp(C yprinus carpio var. Jian). An F1 population comprising 94 Jian carp individuals was mapped using 254 microsatellite markers. The genetic map spanned 1 381.592 c M and comprised 44 linkage groups,with an average marker distance of 6.58 c M. We identified eight quantitative trait loci(QTLs) for body weight(BW) in seven linkage groups,explaining 12.6% to 17.3% of the phenotypic variance. Comparative mapping was performed between Jian carp and mirror carp( Cyprinus carpio L.),which both have 50 chromosomes. One hundred and ninety-eight Jian carp marker loci were found in common with the mirror carp map,with 186(93.94%) showing synteny. All 44 Jian carp linkage groups could be one-to-one aligned to the 44 mirror carp linkage groups,mostly sharing two or more common loci. Three QTLs for BW in Jian carp were conserved in mirror carp. QTL comparison suggested that the QTL confidence interval in mirror carp was more precise than the homologous interval in Jian carp,which was contained within the QTL interval in Jian carp. The syntenic relationship and consensus QTLs between the two varieties provide a foundation for genomic research and genetic breeding in common carp. 相似文献
10.
Three artificial gynogenetic clones of silver carp were produced for the analysis of restriction enzyme digestion patterns
of ND5-ND6 region from mtDNA of the clones. It is revealed that all intraclonal individuals shared completely the same digestion
patterns but among interclonal individuals did not. The three clones were mixed and cultured in a pond together for two years,
and restriction endonuclease digestion patterns of ND5–ND6 were used as genetic markers to assess the growth performance of
each clone.
Project supported by the National Natural Science Foundation of China (No. 39830300). 相似文献
11.
1 INTRODUCTION Silver carp (Hypophthalmichthys molitrix) is an important species in freshwater fisheries and ranks the first in world fish production (Li, 1993). China has a long history of aquaculture of silver carp that is very difficult for selective breeding because it has a long life cycle. However, development of cytoge-netics and modern molecular genetics built up a strong impact to the research on selective breeding. A rapid, efficient approach for establishment of a pure line of… 相似文献
12.
将丁香油溶与乙醇混合进行对福瑞鲤麻醉,结果表明:丁香油与70%乙醇按1︰1.5得到的混合液与丁香油相比,使用3min时对福瑞鲤具有更好的麻醉效果;混合液的半致死浓度为0.2233mL/L,0.1 mL/L混合液在鱼密度达到1尾/L时的麻醉率最高;将处理过的样品血清进行生化指标检测,丁香油处理样品的CREA比对照显著高,而混合液处理样品所有血清指标与对照差异都不显著。 相似文献
13.
ＩＮＴＲＯＤＵＣＴＩＯＮＭｉｃｒｏｃｙｓｔｉｓａｅｒｕｇｉｎｏｓａｗａｓｔｈｅｍａｉｎｂｌｏｏｍ ｆｏｒｍｉｎｇｓｐｅｃｉｅｓｉｎＤｏｎｇｈｕＬａｋｅ;ｏｃｃｕｒｒｅｄｏｎｌｙｓｐｏｒａｄｉｃａｌｌｙｉｎｔｈｅ 1 950ｓ,ｉｎｃｒｅａｓｅｄｒａｐｉｄｌｙｉｎｎｕｍｂｅｒｉｎｔｈｅ 1 960ｓ.Ｆｒｏｍｔｈｅｍｉｄｄｌｅｏｆｔｈｅ 1 970ｓｔｏｔｈｅｍｉｄｄｌｅｏｆｔｈｅ 1 980ｓ,ｔｈｉｃｋｌａｙｅｒｏｆｉｔｓｂｌｏｏｍｃｏｖｅｒｅｄｔｈｅｌａｋｅｓｕｒｆａｃｅｅｖｅｒｙｓｕｍｍｅｒ,ａｔｔｒａｃｔ ｉｎｇｆｏ… 相似文献
14.
对网围养殖区内草鱼的活动声波进行了采集与分析,并将采集的声波进行了回放。结果表明,草鱼网围养殖区声波频率范围为0~3.2 kHz,整个频段内没有宽带波峰。在草鱼饥饿、食饵和饱食的不同状态下养殖区内的水声特性有一定的差异。研究表明在网围养殖区通过声波回放能对草鱼起到诱集作用,在投饵回放、投饵不回放及不投饵回放声波的情况下,草鱼的响应时间分别为2.55、3.504、.80 min,存在显著差异。回放持续性声波和间隔性声波在响应时间上不存在显著差异。 相似文献
15.
GAO Ruichang XUE Changhu YUAN Li ZHANG Yongqin XUE Yong SUN Yan FENG Hui 《中国海洋大学学报(英文版)》2007,6(4):398-402
Myosin subfragment-1 was prepared from the myofibrils of bighead carp (Aristichthys nobilis). The myosin subfrag- ment-1 was proved to have the activity of tripolyphosphatase (TPPase) responding to the hydrolysis of sodium tripolyphosphate (STPP). The optimum temperature and pH for the TPPase of myosin subfragment-1 were 30℃ and pH 5.0, and at pH 8.0 the TPPase also showed a high activity. Mg2 was necessary to TPPase. The TPPase activity of myosin subfragment-1 was activated by Mg2 under low concentrations, but was inhibited when the concentration was over 17 mmolL-1. The TPPase activity was also affected by KCl. The optimum concentration of KCl for TPPase was 0.3 molL-1 under the condition of 17 mmolL-1 Mg2 . The TPPase activity was significantly inhibited by EDTA-Na2. Reagents such as KBr, KI and KIO3 could inhibit the TPPase effectively. K2Cr2O7 as well as KMnO7 and KNO3 exhibited weak inhibiting effects. The TPPase converted STPP to pyrophosphate (PP) and orthophosphate (Pi) stoichiometrically with a KM of 3.2 mmolL-1. 相似文献
16.
The intestinal bacteria of vertebrates form a close relationship with their host.External and internal conditions of the host,including its habitat,affect the intestinal bacterial community.Similarly,the intestinal bacterial community can,in turn,influence the host,particularly with respect to disease resistance.We compared the intestinal bacterial communities of grass carp that were collected from farm-ponds or a lake.We conducted denaturing gradient gel electrophoresis of amplified 16S rRNA genes,from which 66 different operational taxonomic units were identified.Using both the unweighted pair-group method with arithmetic means clustering and principal component analysis ordination,we found that the intestinal bacterial communities from the two groups of pond fish were clustered together and inset into the clusters of wild fish,except for DF-7,and there was no significant correlation between genetic diversity of grass carp and their intestinal bacterial communities(Mantel one-tailed test,R=0.157,P=0.175).Cetobacterium appeared more frequently in the intestine of grass carp collected from pond.A more thorough understanding of the role played by intestinal microbiota on fish health would be of considerable benefit to the aquaculture industry. 相似文献
17.
The temporal and spatial distributions of zooplankton communities in the upper, middle, and lower reaches of the Xin＇anjiang Reservoir, Zhejiang, China, were investigated monthly, between 2009 and 2010. Silver carp （Hypophthalmichthys moBtrix） and bighead carp （Aristichthys nobilis） dominated the pelagic fish community of this large, deep reservoir. Cladocerans were distributed evenly throughout the reservoir. Rotifers were mainly found in the upper reaches, while copepods tended to assemble in the lower reaches. The Pearson correlation analysis and stepwise multiple regression were used to identify the major physicochemical gradients influencing community variations. Zooplankton community distributions were influenced by water temperature, dissolved oxygen, phosphorus, nitrogen, and silicon. Excess nutrients, in particular silicon, stimulated rotifer growth. Based on these findings, it is possible to use rotifer density as a bioindicator of eutrophic status in deep reservoir ecosystems. 相似文献
18.
地衣芽孢杆菌在异育银鲫日粮中的应用 总被引：1，自引：0，他引：1
在异育银鲫基础日粮中分别添加质量分数0.01%、0.02%、0.03%、0.04%的地衣芽孢杆菌,测定了鱼体的生长及食糜植酸酶活性等。结果表明:与对照组相比,添加量0.01%、0.02%、0.03%组的增重率分别显著提高了12.46%、18.59%、18.84%;添加量0.02%、0.03%组的磷表观消化率分别提高37.63%、35.03%(P<0.05);饵料系数降低了0.52、0.57(P<0.05),其他组差异不显著。与对照组相比,0.03%组食糜植酸酶活性提高50.79%、0.04%组肝体比降低20.91%(P<0.05),其他组差异不显著。因此在异育银鲫日粮中添加地衣芽孢杆菌提高了机体酶活性,促进了鱼体生长。 相似文献
19.
Microcystis bloom, one of the most objectionable characteristics of eutrophication in tropical and subtropical waters, occurred in Donghu Lake (East lake) of Wuhan every summer from the 1970s up to 1984, but from 1985 up to now failed to occur there. The cause of its disappearance rema-ined in obscurity until recently. In situ enclosure experiments in the lake for three years showed that the stocking of the filter-feeding silver carp ( Hypophthalmichthys molitrix ) and big-head carp (Aristichthys nobilis ) played a decisive role in eliminating Microcystis bloom from the lake; but that recurrence of the bloom is possible under certain conditions. This paper presents the details and the results of enclosure ex-periments. The authors‘ analysis of fish biomass data obtained by echo-sounding and the fishery produc-tion of the lake over the years, revealed that the recurrence of Microcystis bloom can be prevented so long as the combined biomnss of silver carp and big-head carp remains at or exceeds 50 g per cubic meter of lakewater, as was the case in the lake‘s 1985 fish yield of 1015 t. 相似文献
20.
建鲤与黄河鲤的RAPD分子标记及其杂交优势的遗传分析 总被引：3，自引：0，他引：3
利用RAPD技术对建鲤、黄河鲤及其杂交子代进行了遗传分析,筛选的33个引物共扩增出155条带,其中多态性片段为105条,片段S18-1600、S472-300具有种的特异性,可作为鉴别建鲤与黄河鲤的分子遗传标记。建鲤、黄河鲤及其正、反交子代群体内的遗传相似系数分别为0.8240、0.7921、0.7920、0.8569,黄河鲤与正交F1具有较高的遗传变异水平,反交F1变异最小。正交F1、反交F1与亲本(建鲤、黄河鲤)的遗传距离分别为0.2233、0.2436、0.1749、0.2026,说明子代均继承了较多的建鲤的遗传物质。分析了子代与亲本的RAPD标记类型以及各类型的条带数。应用PIT标记系统测定了子代的杂种优势并探讨了优势产生的遗传机理。 相似文献