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1.
Analysis of stomach contents of samples of clupeid fiishes (Japanese anchovy, half-fin anchovy, zunas' scaled sardine, rednosed glassnose and tapertail anchovy) collected from the catches of a 1982-1984 fishery resource survey showed they are zooplanktonivorous. Similar food groups, such as copepoda, Chaetognatha, Amphipoda and Mysidacea were found in the stomach. Dietary similarity coefficients were studied to evaluate the degree of similarity in the dietary species-pairs.Sea-sonal variation is discussed. 相似文献
2.
Analysis of stomach contents of samples of clupeid fishes (Japanese anchovy, half-fin anchovy, zunas' scaled sardine, rednosed
glassnose and tapertail anchovy) collected from the catches of a 1982–1984 fishery resource survey showed they are zooplanktonivorous.
Similar food groups, such as copepoda. Chaetognatha, Amphipoda and Mysidacea were found in the stomach. Dietary similarity
coefficients were studied to evaluate the degree of similarity in the dietary species-pairs. Seasonal variation is discussed.
Contribution No.2050 from the Institute of Oceanology, Academia Sinica. 相似文献
3.
Anchovy (Engraulis japonicus), a small pelagic fish and food of other economic fishes, is a key species in the Yellow Sea ecosystem. Understanding the mechanisms of its recruitment and biomass variation is important for the prediction and management of fishery resources. Coupled with a hydrodynamic model (POM) and a lower trophic level ecosystem model (NEMURO), an individual-based model of anchovy is developed to study the influence of physical environment on anchovy’s biomass variation. Seasonal variations of circulation, water temperature and mix-layer depth from POM are used as external forcing for NEMURO and the anchovy model. Biomasses of large zooplankton and predatory zooplankton which anchovy feeds on are output from NEMURO and are controlled by the consumption of anchovy on them. Survival fitness theory related to temperature and food is used to determine the swimming action of anchovy in the model. The simulation results agree well with observations and elucidate the influence of temperature in over-wintering migration and food in feeding migration. 相似文献
4.
Based on two bottom trawl surveys conducted in autumn 2000 and 2001, a total of 1106 stomach samples of Bombay duck Harpadon nehereus between 23–278 mm fork length were collected and analyzed. The results show that Bombay duck prey items consisted of 11 groups or 32 species, of which Apogon lineatus, Leptochela gracilis, Acetes chinensis, and Euphausia pacifi ca were the dominant prey species. Ontogenetic variations were found in feeding habits and feeding activity of Bombay duck. Feeding activity was highest in fi sh smaller than 50 mm, lowest in fi sh between 50 and 99 mm, and then increased with increasing size thereafter. As Bombay duck size increased, fi sh prey increased in importance, whereas euphausiids and decapods decreased in importance. Different trophic guilds were observed in feeding habits across the examined size range. Bombay duck smaller than 50 mm were zooplanktivores, mainly feeding on zooplankton and fi sh larva; those between 50 and 149 mm were generalist predators, mainly feeding on pelagic shrimps, demersal shrimps and fi shes; and those larger than 150 mm were piscivores, mainly feeding on fi shes. 相似文献
5.
An alkaline protease from Acetes chinensis was purified and characterized in this study. The steps of purification include ammonium sulfate precipitation, ion-exchange
chromatography with Q-sepharose Fast Flow, gel filtration chromatography with S300 and the second ion-exchange chromatography
with Q-sepharose Fast Flow. The protease was isolated and purified, which was present and active on protein substrates (azocasein
and casein). The specific protease activity was 17.15 folds and the recovery was 4.67. The molecular weight of the protease
was estimated at 23.2 kD by SDS-PAGE. With azocasein as the susbstrate, the optimal temperature was 55°C and the optimal pH
value was 5.5. Ion Ca2+ could enhance the proteolytic activity of the protease, while Cu2+, EDTA and PMSF could inhibit its activity. 相似文献
6.
The carbohydrate and lipid contents in two planktonic crustaceans, i. e.Pseudeuphausia sinica andAcetes chinensis sampled from Xiamen coastal waters were estimated. InP. sinica, the contents of carbohydrates (in dry weight) and lipids varied from 2.19–2.33% and 21.2–21.9% respectively; inA. chinensis from 1.74–2.55% and 14.43–15.10% respectively. The analyses of fatty acids by gas-chromatograph (Model 103) showed that eight
fatty acids of 14∶0, 15∶0, 16∶0, 17∶0, 18∶0, 18∶2, 20∶2 and 22∶2 were found in these two animals, that 16∶0, 18∶0, 18∶2, and
20∶2 formed the major constituents with 91.08% (P. sinica) and 74.80% (A. chinensis) of the total fatty acids, and that the values of odd carbon types (15∶0 and 17∶0) were fairly low, 4.47% and 3.36% respectively.
Three monosaccharides: glucose, fructose, and galactose detected by high-liquid chromatograph (Waters 208) accounted for more
than 60% of the total carbohydrates, especially the glucose, exceeding by 40%. 相似文献
7.
The morphology of larval and 1st postlarval stages ofPenaeus penicillatus are described. Results from comparative studies on larval development ofP. penicillatus, P. merguiensis andP. chinensis are as follows:
These three species could not be identified during their naupliar stages.
In the 1st protozoea, the antennule L1/L2 value is 1.7–2.0 inP. merguiensis, but less than 1.7 inP. chinensis andP. penicillatus; in the 2nd protozoea, the supra-orbital spine inP. chinensis is not bifurcated, while those ofP. merguiensis andP. penicillatus are bifurcated; in the 3rd protozoea, there is a minute (or no) dorso-median spine on the posterior margin of the 1st and
2nd abdominal somite inP. chinensis, but they are prominent inP. merguiensis andP. penicillatus. In the mysis and 1st postlarval stages,P. chinensis differs fromP. merguiensis andP. penicillatus in having 9 (8 in the other 2 species) long setae on the exopod of pereopods 1–3; additionally, one dorsal tooth appears
on the rostrum ofP. chinensis in the 2nd mysis and that of the other 2 species in the 3rd mysis;P. chinensis has 2 (mostly) or 1 dorsal tooth on the rostrum in the 3rd mysis and 2–3 in the 1st postlarva, whileP. penicillatus andP. merguiensis have only 1 in the 3rd mysis and 1st postlarva. Comparative studies on larval development showedP. penicillatus has closer affinity withP. merguiensis than withP. chinensis.
Contribution No. 2218 from the Institute of Oceanology, Chinese Academy of Sciences 相似文献
8.
Chinese shrimp (Fenneropenaeus chinensis) is an economically important aquaculture species in China. However, cytogenetic and genomic data is limited in the organism
partly because the chromosomes are difficult to isolate and analyze. In this study, fluorescence in-situ hybridization (FISH)
was used to identify the chromosomes of F. chinensis. The 5S ribosomal RNA gene (rDNA) of F. chinensis was isolated, cloned and then used as a hybridization probe. The results show that the 5S rDNA was located on one pair of
homologous chromosomes in F. chinensis. In addition, triploid shrimp were used to evaluate the feasibility of chromosome identification using FISH and to validate
the method. It was confirmed that 5S rDNA can be used as a chromosome-specific probe for chromosome identification in F. chinensis. The successful application of FISH in F. chinensis shows that chromosome-specific probes can be developed and this finding will facilitate further research on the chromosomes
of penaeid shrimps. 相似文献
9.
Anchovy is a key species in the Yellow Sea ecosystem. An accurate estimate of anchovy abundance is vital for the management of the anchovy stock and measurement of the ecosystem response to changes in anchovy abundance. However, the acoustic fish abundance estimate may be biased by 30%?C40% if the fat-content induced target strength variation is not taken into account. We measured the monthly variation in the fat content of anchovy (Engraulis japonicus) in the Yellow Sea, and evaluated the potential effect of variation in fat content on the acoustic assessment of anchovy abundance. The fat content of anchovy varied seasonally, with two maxima and two minima in a year. The highest fat content (14.75%) was measured in the pre-spawning period in May, and the lowest fat content (2.48%) was measured during the post-spawning period in October. Fat content appeared to correlate with water content, but not body size. Assuming that the target strength is decreased by 0.2dB for every 1% increase in fat content, the seasonal difference in the target strength of anchovy may be as high as 2.45 dB. Given this, the acoustic abundance estimate may be biased by between 43% and 76%. Our results highlight the need for more information on the changes in fat content of fishes whose abundance is estimated by acoustic surveys. 相似文献
10.
11.
Relatively short historical catch records show that anchovy populations have exhibited large variability over multi-decadal timescales. In order to understand the driving factors (anthropogenic and/or natural) of such variability, it is essential to develop long-term time series of the population prior to the occurrence of notable anthropogenic impact. Well-preserved fish scales in the sediments are regarded as useful indicators reflecting the fluctuations of fish populations over the last centuries. This study aims to validate the anchovy scale deposition rate as a proxy of local anchovy biomass in the Yellow Sea adjoining the western North Pacific. Our reconstructed results indicated that over the last 150 years, the population size of anchovy in the Yellow Sea has exhibited great fluctuations with periodicity of around 50 years, and the pattern of current recovery and collapse is similar to that of historical records. The pattern of large-scale population synchrony with remote ocean basins provides further evidence proving that fish population dynamics are strongly affected by global and basin-scale oceanic/climatic variability. 相似文献
12.
As fish is one source of the ‘big eight’ food allergens,the prevalence of fish allergy has increased over the past few years.In order to better understand fish allergy,it is necessary to identify fish allergens.Based on the sera from fish-allergenic patients,a 28 kDa protein from local mackerel (Scomber japonicus),which has not been reported as a fish allergen,was found to be reactive with most of the patients’ sera.The 28 kDa protein was analyzed by MALDI-TOF-MS (Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry).Mascot search in NCBI database (Date: 08/07/2010) showed that the top protein matched,i.e.triosephosphate isomerase (TPI) from Xiphophorus maculatus and Poecilia reticulata,had a mowse (molecular weight search) score of 98.In addition,TPI from Epinephelus coioides also matched this mackerel protein with a mowse score of 96.Because TPI is con-sidered as an allergen in other non-fish organisms,such as lychee,wheat,latex,archaeopotamobius (Archaeopotamobius sibiriensis) and crangon (Crangon crangon),we consider that it may also be an allergen in mackerel. 相似文献
13.
The excitation energy transfer from phycobiliproteins to thylakoid PSII of higher plants was investigated. When incubated
with spinach thylakoids, phycobiliproteins isolated from red and blue-green algae transferred light energy absorbed to spinach
PSII. The efficiency of energy transfer was dependent on the kind of phycobiliproteins used. If spinach thylakoids were replaced
by the thylakoids ofBrassica chinensis, R-phycoerythin or C-phycocyanin did not transfer their excitation energy to PSII ofBrassica chinensis unless allophycocyanin was present.
Contribution No. 69 from the Experimental Marine Biology Laboratory IOAS. 相似文献
14.
刘静 《中国海洋湖沼学报》1997,15(3):224-226
ImOUocrON0verevoluti0narytirne,intetspeCiliccomPctitioncanresultincharactedisplacementSthatfadiitateresourcepartitioningamongspedesffeper,l985,Wilirarnanayake,l99O).Fisharenotablyopportunisticintheirfeding,toknowWhereandhowtheybowilloftenprovidemoreinsightintotheirerelogythansbolyknowingtheactUalcomPonentSoftheirdiet(Motta,l988,HUmPhrieS,l993).ArmrdinglymorphologicalcomParisonsamongcoxiccutwspchprovidemportantinfonnationnotonlytosySteInatistsfaedwithtaxonondcprobbo,butaIsot0erelogistS… 相似文献
15.
比较了4种常用蛋白酶对中国毛虾的酶解效果,筛选出胰蛋白酶和枯草杆菌蛋白酶为最佳用酶,并利用正交试验优化了水解条件,在各自最佳水解条件下采用先加胰蛋白酶再加枯草杆菌蛋白酶的酶解方式对中国毛虾进行联合双酶水解,水解度可达67 .83%。 相似文献
16.
The goal of this study was to investigate the behaviour of rainbow trout (n=30), Oncorhynchus mykiss, in small raceways when either self-feeders (T2) or hand-feeding (t2) were used. The method of food delivery in T2 was defensible
while that of t2 was indefensible. Fish in both raceways were subjected to restricted feeding (RF) for 25 days. Food was available
in the morning (09:00–10:00) in the downstream area and in the afternoon (16:00–17:00) in the upstream area of the raceways.
The results showed that the behaviour of rainbow trout was significantly different under interference competition (T2) for
food compared with that under scramble competition (t2). RF in T2 fish limited food availability to meal times when feeding
rewards were available while t2 fish only responded to the location of food delivery. The aggressive fish in T2 were dominant,
and t2 fish at high densities showed intense social interactions under the indefensible pattern of food distribution; these
interactions did not dampen to a minimum level to suppress the development of dominance hierarchies. Further, the stocking
density did not break down the dominance hierarchies between the T2 fish. This suggests that decreased efficiency in the search
for food or inefficient foraging, induced by interference competition at high densities, affected the behaviour of rainbow
trout. 相似文献
17.
This pathogenic study shows that the viral diseases of Chinese prawns (Penaeus chinensis, O'sbeck) is due to three kinds of viruses: epithelium envelope baculovirus ofPenaeus chinensis (EEBV-PC, detected by the authors in 1993), infections hypodermal and hematopoietic necrosis virus, and hepatopancreatic
parvo-like virus, and that the first two viruses seem to be the main pathogens of the epidemic in the northern regions in
1993. 相似文献
18.
The Chinese shrimp Penaeus (Fenneropaeneus) chinensis is an important species in marine fishery and aquaculture in China. A female Chinese shrimp Penaeus (Fenneropaeneus) chinensis was captured from west coast of the Korean peninsula and mated with a “Yellow Sea No. 1” male to produce the first filial
generation (F1) 100 F2 full-sib progeny from brother-sister crosses between F1 families was used for the mapping study. A genetic linkage map of the Chinese shrimp was constructed, based on 354 markers,
including 300 amplified fragment length polymorphism (AFLP) markers, 42 microsatellite (SSR) markers, and 12 randomly amplified
polymorphism (RAPD) markers. Forty-seven linkage groups (LGs) were identified. The total map length was 4 580.5 cM, with an
average spacing of 11.3 cM, covering 75.8% of the estimated genome size. The construction of this genetic linkage map was
part of a genetic breeding program. This linkage map will contribute to the discovery of genes and quantitative trait loci
(QTLs) in Chinese shrimp. 相似文献
19.
《中国海洋湖沼学报》2016,(5)
The composition and compound-specific isotopes of fatty acids were studied within food webs in the East China Sea.Lipid-normalized stable carbon isotopes of total organic carbon had a good correlation with trophic level.Variations in fatty acid compositions among different species were observed but were unclear.Different dietary structures could be traced from molecular isotopes of selected fatty acids in the Shiba shrimp(Matapenaeus joyneri),the coastal mud shrimp(Solenocera crassicomis) and the northern Maoxia shrimp(Acetes chinensis).Both M.joyneri and S.crassicomis are mainly benthos feeders,while A.chinensis is a pelagic species,although they have a similar fatty acid composition.There was a good correlation for isotopes of arachidonic acid(C20:4n6;ARA) and docosahexaenoic acid(C22:6n3;DHA)among pelagic species from higher trophic levels.The isotopic compositions of DHA in benthic species were more negative than those of pelagic species at the same trophic level.The fact that the diet of benthic species contains more degraded items,the carbon isotopes of which are derived from a large biochemical fraction,may be the reason for this variation.A comparative study of benthic and pelagic species demonstrated the different carbon sources in potential food items and the presence of a more complex system at the watersediment interface. 相似文献
20.
Stable isotope methods can be used to determine the food sources and prey items of aquatic organisms accurately and reliably.
This study examined the relative contribution of artificial foods (the formulated feed and Artemia) and natural foods to shrimp growth in an intensive Fenneropenaeus chinensis pond by using carbon and nitrogen stable isotopes. The results showed that the nutrition utilization efficiency of the harvested
shrimp was low, only 33.18% of feed nitrogen and 21.73% of feed carbon being converted to shrimp flesh. Our stable isotope
results showed that the shrimp obtained nutrition for maximum growth from artificial foods, whose contribution was 93.5%,
with the remaining attributed to the natural foods. However, there was 0.94 t harvested shrimp derived from natural foods
(the rest of 13.56 t harvested shrimp derived from artificial foods) in 1ha intensive pond with a shrimp production of 14.50
t ha−1. Therefore, unit area shrimp production can be increased by increasing the contribution proportion of natural foods in intensive
shrimp farming. 相似文献