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1.
正高度不饱和脂肪酸是多不饱和脂肪酸中具有二十个碳原子以上,含3个或3个以上双键的脂肪酸~[1-4],主要有花生四烯酸(C20:4n-6)、二十二碳六烯酸(C22:6n-3)和二十碳五烯酸(C20:5n-3)等~[5-12]。高度不饱和脂肪酸影响机体脂类代谢~[13]、基因表达~[14-15]、细胞膜功能~[16]、机体免疫~[17-18]及血液生理生化特性~[19-20]等,对水生动物的生长、发育和繁  相似文献   

2.
[目的]建立了水产品中辛硫磷、倍硫磷和蝇毒磷3种有机磷农药的检测方法。[方法]样品经酸化乙腈提取,PSA吸附剂分散固相萃取净化,超高效液相色谱-串联质谱在多反应离子监测模式下检测,基质匹配外标法定量。结果加标浓度在10~100μg/kg范围内,线性相关系数(R)大于0.99。3种有机磷农药的平均回收率范围为65.8%~101.0%,RSD范围为11.4%~16.0%。本方法检出限为10μg/kg,定量限为20μg/kg。[结论]该方法可用于水产品中辛硫磷、倍硫磷和蝇毒磷等3种有机磷农药残留的同时测定。  相似文献   

3.
蛭弧菌在水产养殖中应用研究进展   总被引:1,自引:0,他引:1  
正蛭弧菌是一类专门寄生于其他细菌并能导致其裂解的革兰氏阴性菌,对多种致病菌具有良好的裂解效果~[1],属于蛭弧菌科,比一般细菌小,能通过细菌滤器,广泛存在于土壤、河流、下水道污泥等环境中。蛭弧菌不侵染真核细胞,对人和动物无致病性~[2-3],薛恒平等~[4-6]报道了蛭弧菌对仔鸡、小鼠、鲫鱼(Carassius auratus)的生长没有毒害作用。蛭弧菌作为"活性抗生素"在农牧业、医学以及环保方面  相似文献   

4.
为了解乌苏里拟鲿对氧化钙、硫酸铜硫酸亚铁合剂(5∶[KG-*1/2]2)、三氯异氰尿酸、敌百虫、聚维酮碘、氯化钠等6种常用渔药的耐受性,在水温28±2 ℃,pH值7.2~8.3,溶氧量4.3~5.6 mg·L-1条件下,将全长3.3~5.8 cm、体质量0.32~1.46 g的当年鱼苗放入不同浓度的上述6种药物的药液中进行耐受性试验。试验结果:聚维酮碘、硫酸铜硫酸亚铁合剂(5∶[KG-*1/2]2)、敌百虫、三氯异氰尿酸、氧化钙、氯化钠对乌苏里拟鲿的96 h半致死浓度依次递减;6种药物对乌苏里拟鲿的安全浓度依次为0.01、0.01、0.06、0.25、7.12和3 347 mg·L-1,均低于防治鱼病常规使用浓度。结果表明,乌苏里拟鲿对氧化钙、硫酸铜硫酸亚铁合剂(5∶[KG-*1/2]2)、三氯异氰尿酸、敌百虫、聚维酮碘的耐受性较弱,应慎用;对氯化钠的耐受性较强,可以用2 %的浓度进行药浴,当水温低于26 ℃,药浴时间少于55 min时尚属安全。  相似文献   

5.
凡纳滨对虾亲虾性腺成熟节律和交配率   总被引:4,自引:1,他引:4       下载免费PDF全文
在水温(27±2)℃、盐度29±2、pH 7.8~8.5、光强1 000 lx的条件下,对来自中国台湾省的体质量为35~45 g的凡纳滨对虾(Litopenaeus vannameiBoone 1931)亲虾的性腺成熟节律和交配进行了为期73 d的繁育实验,样品为1 300对,3个批次。结果表明,雌虾术后卵巢成熟率分4期:Ⅰ期(1~9 d)入池适应术后效应期;Ⅱ期(10~16 d)低成熟率期,Ⅲ期(17~51 d)成熟率渐上升期,Ⅳ(52~73 d)平稳期;雄虾精荚形成率分3期:Ⅰ期(1~12 d)入池适应与术后效应期;Ⅱ期(13~51 d)平缓上升期,Ⅲ期(52~73 d)平稳期。在95%的概率保证程度下,雌亲虾卵巢成熟率为9.73%,波动区间9.14%~11.53%;雄虾精荚形成率6.63%,波动区间5.87%~7.38%;平均交配率为61.43%,波动区间58.85%~64.00%。在繁殖过程中,雌虾卵巢再成熟时间间隔9.68 d,可多次成熟的次数19.49次,雄虾精荚再形成时间15.10 d,可多次形成的次数为12.50次。此外还就影响雌虾卵巢成熟和雄虾精荚形成的因素以及如何提高交配率进行了详细的讨论。[中国水产科学,2006,13(4):579-584]  相似文献   

6.
建立了以高效液相色谱-串联质谱法同时检测养殖池塘沉积物中喹诺酮类、四环素类、磺胺类16种抗生素的分析方法。沉积物样品经提取液[磷酸盐缓冲液(pH=3)∶乙腈=1∶1]提取后,以MAX-HLB串联小柱净化富集,在HPLC/MS/MS多反应监测模式下进行定性及定量分析,当目标化合物添加浓度为10μg/kg和100μg/kg时,沉积物中喹诺酮类、四环素类、磺胺类的加标回收率分别为67.6%~107.1%,63.8%~118.7%,67.1%~116.4%,相对标准偏差在5.1~12.9。以3倍信噪比估算出喹诺酮类、四环素类、磺胺类的检出限分别为0.14~0.64、1.8~3.9、0.18~0.42μg/kg。应用此方法检测21口池塘的43个沉积物样品,结果表明,该方法操作简便,重现性好,可用于池塘沉积物中抗生素的检测。  相似文献   

7.
[目的]建立一种使用液相色谱-串联质谱联用仪快速准确检测池塘沉积物中痕量氯霉素残留的方法,为水产品中氯霉素污染来源的排查提供技术支持。[方法]底泥经润湿后,经乙酸乙酯水饱和溶液提取,Sep-Pa K C_(18)固相萃取柱净化,Shim-Pack XR-ODS色谱柱分离,采用甲醇和水为流动相,并用梯度洗脱对待测物进行分离,以氘代氯霉素(氯霉素-D5)为内标,采用负离子扫描,多反应监测模式(MRM),定性离子对m/z为321→152.0,256.8,定量离子对m/z为321→152.0。[结果]氯霉素类药物在0.5~10.0 ng/m L范围内线性良好,相关系数均大于0.99,本方法的检出限为0.1μg/kg,定量限为0.3μg/kg。3个加标水平(0.5、1.0和5.0μg/kg)的平均回收率为90.1%~96.6%,相对标准偏差为2.4%~7.0%。[结论]实验结果符合氯霉素药物残留检测的相关法规要求,适用于淡水池塘沉积物中氯霉素残留的定性定量检测。  相似文献   

8.
韩伟 《水产养殖》2016,(11):38-39
正菲律宾蛤仔(Ruditapes philippinarum)是我国四大传统养殖贝类之一,俗称花蛤、蚬子等,多栖息于风浪较小、水流通畅并有淡水注入的内湾中低潮区的泥沙滩涂上~[1-2]。寿光蚂蚬是寿光市别具特色的菲律宾蛤仔品种,由于当地独特的气候、水质与底质等条件,其贝壳厚度和硬度大,肉质结实而富有弹性,口感极佳,深受市场欢迎,更因此成为国家农产品地理标志产品~[3]。寿光市位于渤海莱州湾南畔,  相似文献   

9.
张涛  倪勇  李长松  庄平 《海洋渔业》2006,28(3):263-264
王幼槐[1]1990年在《上海鱼类志》中报道上海地区有3种鳑鮍,即中华鳑鮍Rhodeus sinensisGünther[2]、高体鳑鮍Rhodeus ocellatus(Kner)[3]和彩石鳑鮍Rhodeus lighti(Wu)[4]。经国内外学者研究,彩石鳑鮍为中华鳑鮍的同物异名[5-9]。2006年6月在崇明中兴镇内河采到3 ind鳑鮍属鱼类标本。经鉴定为方氏鳑鮍Rhodeus fangi(M iao)[10],系上海地区鱼类新记录。本种与上述2种的主要区别是体侧中央银蓝色纵纹从尾鳍基向前伸达背鳍起点前方4~5鳞处,而后两种此纵纹不伸达背鳍起点[5-6,11]。现报道如下。方氏鳑鮍Rhodeus fangi(M iao),1934采集时间…  相似文献   

10.
<正>鸢乌贼(Sthenoteuthis oualaniensis)属头足纲柔鱼科鸢乌贼属,是世界重要的大洋性经济头足类之一,广泛分布于印度洋、太平洋的热带和亚热带海域[1-2]。鸢乌贼在印度洋西北部海域和中国南海的资源量较为丰富[3-4],根据联合国粮食及农业组织估算,其总资源量约为800~1120万t[5]。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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。  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
20.
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.  相似文献   

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