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1.
菊花心江蓠(Gracilaria lichevoides)营养成分分析及评价   总被引:1,自引:0,他引:1  
利用氨基酸分析仪、气相色谱和电感耦合等离子体发射光谱技术分析菊花心江蓠(Gracilaria lichevoides)的氨基酸、脂肪酸、矿物质等主要营养成分及构成比例。结果表明,菊花心江蓠中的主要成分是粗纤维和粗蛋白质,分别占藻体的5.4%和13.8%;含有18种氨基酸,氨基酸总量(TAA)为13.5%,必需氨基酸(EAA)占总氨基酸(TAA)的35.5%;从菊花心江蓠中分析出4种脂肪酸,其中不饱和脂肪酸占脂肪酸总量的59.7%,特别是16碳和18碳脂肪酸比较丰富;矿物质含量丰富,尤其是Ca、Mg、K、P、Na、Fe等。因此,菊花心江蓠可作为人类和动物一种高膳食纤维、高蛋白、低脂肪,富含矿物质元素的天然理想食源。  相似文献   

2.
由台湾引进粗江蓠种,在罗源湾海区采用浮筏式开展养殖试验,对养殖海区的水温、盐度、pH值、光照等环境因子适宜条件,进行初步的探索,并取得阶段性成果。  相似文献   

3.
本文探讨了用户外水槽(50L,0.23m~2),流水栽培方式,提克江蓠在栽培密度(kg/m~2),营养盐输入量(总氮输入量/天),流速与生长和产量的关系。在密度为2.0—3.0kg湿重/m~2的条件下获得最佳年产量。在满足最低氮营养需求条件下江蓠的产量与下列几点无关:一、营养盐浓度;二、氮的输入量;三、氮源的形态包括NH_4+—N和NO_3—N。而只与流速密切相关。在最适条件下连续栽培一年,定期收获产量为34.8克干重/m~2·天或127吨干重/公倾·年。  相似文献   

4.
2012年夏季在爱莲湾,对采用碳酸氢铵防除养殖龙须菜(Gracilaria lemaneaformis)上的污损生物多棘麦秆虫(Caprella acanthogaster)的效果进行了研究,探讨了碳酸氢铵浓度及处理时间对多棘麦秆虫脱落率和死亡率的影响。实验的3个处理时间分别为5、10、15 min,碳酸氢铵浓度分别为0.5、0.6、0.7、0.8、0.9、1.0、2.0、3.0、4.0、5.0 g/L。结果表明,碳酸氢铵浓度、处理时间对多棘麦杆虫脱落率或死亡率均有显著影响(P0.05)。随着浓度的升高、处理时间的延长,多棘麦杆虫脱落率及死亡率都呈逐渐增加的趋势。多棘麦杆虫脱落率(D)或死亡率(M)与浓度(C)之间的关系均符合S型曲线模型lnD=a+(b/C)或lnM=c+(d/C)。在5、10、15 min时,碳酸氢铵对麦杆虫的致死浓度分别为7.36、6.17、3.68 g/L,对应的非离子氨浓度分别为37.72、21.32、14.25 mg/L。  相似文献   

5.
6.
江蓠由于分布广泛、生长快和捞取方便,在琼胶工业中较其他琼胶原藻越来越具有更大的发展前途。Causey、Isaac、Jones、Stokke、藤讓及曾呈奎等,曾就江蓠的生长与生殖等问题进行过一些研究,提供了一些有用的资料。为了进一步了解江蓠的生长、生殖情况,并为我国江蓠增殖途径和方法提供科学资料,我们于1962年4月至1963年5月,在青岛太平湾潮间带就江蓠的自然生长率和生  相似文献   

7.
The fatty acid compositions of brain phosphoglycerides from a freshwater fish, the rainbow trout (Salmo gairdneri), and a marine fish, the cod (Gadus morhua), were determined and compared with those from a terrestrial mammal, the rat. Fish brain lipids were characterized by a higher degree of unsaturation encompassing increased percentages of (n–3)PUFA (226 and 205) and lower percentages of (n–6)PUFA (204 and 224). However the distribution of fatty acids and specific PUFA between different phosphoglycerides was essentially similar in rat and fish brain tissue. PE and PS contained the highest percentages of 226(n–3), PI was characterized by higher 180 and 204(n–6)/205(n–3), and PC had higher 160 and the lowest percentage of PUFA in all species. A generally similar pattern was found in the fish retinal phosphoglycerides except that PC was also rich in 226(n–3). Overall trout brain phosphoglycerides were slightly more unsaturated than the cod lipids but with lower (n–3)/(n–6) ratios whereas cod retinal lipids were more unsaturated than the trout retinal lipids.  相似文献   

8.
《水生生物资源》2000,13(5):327-330
The application of fisheries acoustics in shallow waters opens new fields of observation and allows new methods for abundance estimates. In this paper we deal with echocounting of migrating fish crossing the Beaucaire-Vallabrègues lock, the first obstacle encountered on the Rhône, using a SIMRAD EY500 split-beam sounder, 70 kHz frequency. Two transducers sampled a section of water and evaluated approximately 35% of the lock section, based on a calibration sphere. The number of fish crossing the lock was calculated for each fish lock. Crossing data for the fish were recorded (dates, position, exit time). The present analysis did not allow the identification of the two major species that cross the dam: shad (Alosa fallax) and mullet (Mugil cephalus). The number of fish counted was positively correlated with the catches per unit effort (CPUE) by recreating fishermen below the dam and with increasing water temperature.  相似文献   

9.
ABSTRACT

Mariculturing of horse mackerel is not known in the world. Additionally, limited studies exist on quality changes of smoked horse mackerel at refrigerated temperatures. Therefore, in this study, between 1+ and 2-year-old wild and cultured horse mackerels were hot smoked and stored at refrigerated conditions. Chemical, microbiological, and sensory analyses were performed weekly to investigate quality changes and to determine the shelf stability of the products. The results of thiobarbituric acid, trimethylamine, and total bacteria counts were obtained within the acceptable levels. Although the counts of histamine-forming bacteria increased significantly (p < 0.05) during storage, histamine values were well below the permitted limits set by Food and Drug Administration and European Union (EU). Sensory results showed that both storage groups had 3 weeks of shelf life. Total volatile basic nitrogen values supported sensory results. Therefore, the results indicate that culturing of horse mackerel did not alter the quality during storage at 4 ± 1°C.  相似文献   

10.
In the present study, we examined the long-term effects of environmental salinity, diet (35% and 25% crude protein) and 17-methyltestosterone (MT) on corresponding levels of pituitary and serum growth hormone (GH) and prolactins (tPRL177 and tPRL188) in the tilapia (Oreochromis mossambicus). We observed no discernible patterns in serum GH that would suggest an effect of salinity, diet or MT. However, serum GH levels in all treatments declined at 1 and 3h after first feeding. Serum tPRL177 and tPRL188 were significantly higher in freshwater (FW) than in seawater (SW) and levels were significantly affected by dietary protein. tPRL177 levels were higher in all groups fed a 35% protein diet, but tPRL188 levels were higher only in the groups fed the MT-treated 35% protein diet; only serum tPRL188 levels were affected by MT. Moreover, serum tPRL177 and tPRL188 increased throughout the sampling time-course. Subsequent work using fasted tilapia suggests that first feeding is likely to initiate the post-prandial suppression of serum GH levels. In contrast with the picture observed in blood, pituitary glands of SW animals showed higher levels of GH than FW fish. Pituitary GH was elevated by MT in both FW and SW. We also observed that pituitary tPRL177 and tPRL188 levels were higher in FW fish than in SW fish; tPRL177 and tPRL188 levels were elevated by MT only in FW animals. To assess the somatomedin activity of plasma from FW- and SW-reared tilapia, we measured [35S]-sulfate incorporation into ceratobranchial cartilage explants in vitro. Plasma from SW-adapted tilapia showed greater activity in this assay than plasma from FW-reared tilapia, suggesting that the GH-dependent IGF bioactivity of plasma is higher in SW-reared tilapia. Collectively, these studies suggest that the growth-promoting actions of SW rearing and of MT administration in tilapia may be linked to elevations in GH and/or prolactin (tPRL177 and tPRL188)levels.  相似文献   

11.
The effect of supplemented commercial diets with diethylstilbestrol (DES—15, 30 and 60 mg kg?1) and 17 β-estradiol (E2—30 and 60 mg kg?1), two chemicals commonly used in sex reversal procedure in fish, on survival and growth parameters of juvenile European catfish (Silurus glanis) was evaluated. During the two experiments, lasting 28 days each, fish were kept at temperature 25.2–26.5 °C, pH 7.4–9.3 and oxygen concentration 5.0–7.3 mg O2 dm?3. DES supplementation resulted in depressed growth rate of catfish. In experimental groups fed with E2, no negative effect on growth parameters was found. Both chemicals did not result in observed mortality. In all of the experimental DES groups, hepatosomatic index increased significantly, which suggests negative influence on physiological condition of catfish. DES supplementation significantly changed cytological factors of liver cells and caused hepatic alterations in parenchyma, such as vacuolization and blood congestion. Similarly, supplementation of E2 in food resulted in changes in cytological parameters of hepatocytes. However, E2 did not cause pathological changes within the liver tissue. Histological examination of the catfish gonads showed 19 and 38 % of sterile fish after treatment with 30 and 60 mg kg?1 of DES, respectively. The results suggest that DES served in food could be ineffective in hormonal feminization process of European catfish. No disturbances of sex differentiation process after E2 treatment were observed. However, slight feminization effect in the highest level of E2 treatment group was recorded.  相似文献   

12.
Glutathione S-transferase (GST) isoenzymes were isolated from liver and kidney of carp (Cyprinus carpio) by glutathione affinity chromatography and chromatofocusing. Ten hepatic and eight renal catalytically active isoenzymes were identified. GST subunits from purified isoenzymes were further separated by high-performance liquid chromatography (HPLC) and were used as standards for the experimental sample analysis. Experimental samples came from carp that were fed fish meal (standard diet) or soybean bas ed diets for one year, injected or not with -naphthoflavone (BNF; i.p. injection of 50 mg kg-1). HPLC did not allow us to identify precisely the GST isoenzyme pattern in experimental carp. However, GSTs could be pooled in three categories: homodimeric, heterodimeric and unidentified GST subunits. On this basis, the effect of diet and BNF on the GST isoenzyme pattern was investigated. The homodimer/heterodimer ratio was decreased in liver of carp fed a standard diet and in kidney of both dietary groups. BNF increased the total specific GST activity in liver and kidney. However, the GST isoenzyme pattern was not modified in carp fed the standard diet while tissue specific modifications occured in carp fed the soybean diet. BNF decreased the homodimer/heterodimer ratio in liver and increased it in kidney. Abbreviations: BNF - -naphthoflavone; CDNB - 1-chloro-2,4-dinitrobenzene; GSH - reduced glutathione; GST - glutathione S-transferase; HPLC - high-performance liquid chromatography; SDS-PAGE - SDS-polyacrylamide gel electrophoresis.  相似文献   

13.
The impact of 17-estradiol (E2) and the putative estrogenic compound, 4-nonylphenol (4-NP), on smoltification and vitellogenesis in Atlantic salmon (Salmo salar) was investigated during a 30 day period starting late April. Three groups of fresh water (FW) fish (1 year old, mixed sexes, average weight 23 g) were injected once a week with 50 µg (0.18 µmol) 17-estradiol, 3 mg (13.6 µmol) 4-nonylphenol dissolved in peanut oil, or peanut oil alone as control. Every ten days, subgroups were challenged with 28 ppt seawater (SW) for 24h, and sampled together with subgroups of FW fish. Treatment effects were examined on vitellogenic and osmoregulatory parameters. E2 and 4-NP treatment increased the total calcium and protein level in plasma and the hepatosomatic index of FW fish, both indicating an activated vitellogenesis in the liver. The presence of vitellogenin in the plasma of 4-NP- and E2-treated groups was further indicated by the appearance of a high molecular weight vitellogenin band (550 kDa) in electropherograms produced by native gel electrophoresis. This band appeared in exactly the same position in both the E2- and the 4-NP-treated groups but could not be detected in controls. During the 30 day treatment period, control fish approached the peak of smoltification, as indicated by a distinct silvery appearance, decreasing condition factor, increasing levels of gill Na+,K+-ATPase and improved hypoosmoregulatory performance in the SW-challenge test. Both E2 and 4-NP treatments significantly inhibited the progress of smoltification, as judged by a significant reduction of gill Na+,K+-ATPase activity, relative -subunit Na+,K+-ATPase mRNA expression, gill chloride cell density and a poorer hypoosmoregulatory performance of treated fish. The impaired SW-tolerance of E2- and 4-NP-treated fish was strongly correlated with a decreased gill Na+,K+-ATPase activity. Despite a difference in relative potency, the present study shows that 4-nonylphenol and 17-estradiol may have qualitatively similar inhibitory effects on smoltification and hypoosmoregulatory physiology of Atlantic salmon. Both 4-NP and E2 activated the vitellogenic system, and the study supports the hypothesis that sexual maturation and smoltification are antagonistic, developmental phenomena in salmon. It is suggested that the presence of estrogenic compounds in the environment may negatively influence smoltification and migration in wild stocks of salmon.  相似文献   

14.
In this study, we investigated the physiological alterations during ontogeny for cachara (Pseudoplatystoma reticulatum) and their hybrid larvae (Pseudoplatystoma corruscans?×?P. reticulatum) using lipids and fatty acids as physiological tools to elucidate the basis for differences in these groups?? productivity in an industrial setting. Eggs and larvae samples were collected during January and February of 2008 in the city of Bandeirantes, MS, and were divided into three primary phases: phase I (0?C16?h after fertilization); phase II (24?h after fertilization to 6?days after fertilization); and phase III (7?C25?days after fertilization). The larvae of both groups showed a high degree of similarity, suggesting that the hybrid larvae showed a high level of heritability from the cachara broodstock. Analysis of the total lipid content provided evidence that there is no alteration in lipid concentration during ontogeny for both groups (i.e., the cachara and hybrids). However, the fatty acid profile showed that during the endogenous feeding period (phase II), when the larvae must use the energy reserves from the mother, the cachara larvae used mainly monounsaturated fatty acids for development. This is typical for most fish species, though notably, the hybrids preferentially used saturated fatty acids. Furthermore, certain specific changes demonstrate unique patterns of energy utilization and structural substrates, which may aid in elucidating the empirical differences reported by fish farmers (i.e., that the hybrids perform better than cacharas in captivity).  相似文献   

15.
16.
《Fisheries Research》1988,6(2):105-123
The 1983 El Niño event off the Pacific Coast of North America resulted in increased adult mortality and decreased average size for Oregon's coho and chinook salmon. Actual return of adult coho salmon to the Oregon Production Area in 1983 was only 42% of the pre-season prediction. Coho smolts entering the ocean in the spring of 1983 also survived poorly, resulting in low adult returns again in 1984. Abundance of chinook stocks in southern Oregon was also reduced, as was abundance of Columbia River chinook stocks that show localized ocean distribution. Northerly migrating chinook stocks from the Columbia River showed little or no decline in abundance. The average weight of coho and chinook salmon landed in 1983 by Oregon's commercial troll fishery was the lowest recorded since statistics were first recorded in 1952. Comparison of the length-weight relationship for these fish indicated coho and chinook were in poorer condition in 1983 than in non-El Niño years. Because adult coho salmon returned to hatcheries at a smaller size, the fecundity (eggs per female) in 1983 was reduced from the 1978–1982 average by 24% at coastal hatcheries and by 27% at Columbia River hatcheries. The fecundity of chinook salmon was unchanged at most hatcheries.  相似文献   

17.
《水生生物资源》2002,15(2):87-94
The recruitment of Strangomera bentincki (common sardine) and Engraulis ringens (anchovy) and the relationships with oceanographic conditions in the upwelling ecosystem of central-south Chile were investigated from 1990 to 1998, with emphasis on the 1997–1998 El Niño. Time series of recruitment, biomass, local sea surface temperature, and a coastal upwelling index were used to explore relationships during the spawning (July–August) and pre-recruitment (August–December) periods. The 1997–1998 El Niño caused physical changes in the small pelagic fish habitat off central-south Chile. Anomalous sea surface temperatures (SST) and upwelling indexes began to be detected from May 1997 and persisted into 1998. Recruitment of common sardine showed significantly negative relationship with SST anomalies during the pre-recruitment period, as well as with the upwelling index during the peak of spawning. However, the recruitment of anchovy did not seem to be affected by the environmental changes observed in the 1990s. Instead, the recruitment rate of anchovy showed negative relationship with the recruitment rate of common sardine. We conclude that the conditions of the 1997–1998 El Niño off central-south Chile affected the survival of common sardine offspring, and that the recruitment success of anchovy could be determined by less-abundant cohorts of common sardine through a biological mechanism of interaction.  相似文献   

18.
名称狼牙(鱼叚)虎鱼,学名 Odontamblyo-pus rubicundus(Hamilton-Buchanan)。地方名(鱼乃)鱼(广东唐家湾,香洲)、赤(鱼乃)(广海,闸坡)、白(鱼乃)(唐家湾),红头鳝(广西北海)。隶属于鲈形目,鳗(鱼叚)虎鱼科,狼牙(鱼叚)虎鱼属。特征及近似种体长而侧扁,略呈带状。头大,略呈长方形。吻短,中央稍凸出。眼极小,退化,埋于皮下。口大而斜,下颌和颏部向前上方突出。牙尖锐,长而弯曲,突出唇外。体及头部被小而退化鳞片。背鳍和臀鳍基底均甚长,与尾鳍相连;腹鳍大,左右腹鳍  相似文献   

19.
海(小说)     
[接上期]不出半月,海的爹又成了解放军的俘虏,还是那个十七、八岁的解放军少年给他们上政治课,内容与上一次大同小异。那解放军少年终于发现了海的爹,心里直嘀吐:这小子不出半月怎么又干上国民党了?于是。他问他:“伙计,你怎么专门混在俘虏堆里来领现大洋呢?”他说:“不!不!!别误会”。  相似文献   

20.
鱼王(小说)     
吉林省境内有一个白泉镇,此处山高林密,土质肥沃。山脚处有一泓清泉,终日里水汩汩的往外冒,潺潺地流成一条小河,小河连着大河,直流成一条浩浩荡荡、横贯松辽平原的河流,叫辽河。在辽河源头,一个名叫辽河源屯的村落里,如今出息了一个赫赫有名的主儿,人称“鱼王”狗剩。  相似文献   

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