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1.
优化建立了测定饲料中喹乙醇残留量的高效液相色谱法。样品经甲酸∶15%甲醇水(体积比为1∶99)超声提取,过膜后,高效液相色谱-紫外检测器测定,外标法定量。结果表明,喹乙醇在0.01-0.5 mg/L范围内线性关系良好,相关系数(R~2)为0.9992,当添加水平为0.02-0.5 mg/kg时,加标回收率为76.1%-97.1%,相对标准偏差为3.78%-7.27%。喹乙醇的测定低限为0.02 mg/kg,该方法满足饲料中喹乙醇残留分析的要求,为快速、严格的检测饲料中喹乙醇提供了技术保障。  相似文献   

2.
分别取罗非鱼(Oreochromis niloticus)的肉、脂肪、肝、眼和皮等组织,用氯仿-甲醇(2∶1,v/v)提取,以C17∶0为内标物,利用气相色谱-质谱法(GC/MS)分析了各组织脂肪酸种类及含量。结果显示:罗非鱼各种组织中含有16种脂肪酸,富含多不饱和脂肪酸。脂肪组织中的脂肪酸含量最高,其次是眼睛、肝脏、鱼肉和鱼皮;各组织中饱和脂肪酸(SFA)含量为202~8869 mg/kg,主要为棕榈酸(C16∶0)和硬脂酸(C18∶0);单不饱和脂肪酸(MUFA)含量为293~11219 mg/kg,主要为棕榈油酸(C16∶1)和油酸(C18∶1);多不饱和脂肪酸(PUFA)含量为362~8293 mg/kg,主要是亚油酸(C18∶2)、亚麻酸(C18∶3)和二十二碳六烯酸(DHA,C22∶6);n-6/n-3为1.20~2.46。  相似文献   

3.
研究了提取溶剂、次数以及溶剂的配比对轮虫脂肪提取的影响。分别用氯仿甲醇体积比为2:1、1:1、1:2,苯石油醚体积比2:1、1:1、1:2,丙酮石油醚1:4、3:7、2:3作为提取溶剂,提取冻干轮虫(Brachionus rotundiformis)样品脂肪,测定脂肪含量与皂化值,筛选得出3种提取溶剂的最佳配比;比较提取次数为1~3次间脂肪含量的差异,得出最佳提取次数;将3种最佳配比与索氏提取法(国标)提取样品脂肪进行比较,测定脂肪含量与皂化值。结果显示,在冻干轮虫脂肪提取中,提取次数对样品脂肪含量没产生显著影响(P>0.05);3种溶剂的最佳配比分别为氯仿甲醇2:1、苯石油醚1:2、丙酮石油醚2:3;其中丙酮石油醚2:3处理组的脂肪含量和皂化值分别达到9.71%和198,均显著高于索氏提取法(国标)和其余处理组(P<0.05)。故轮虫脂肪提取1次为宜,最佳溶剂及配比为丙酮石油醚体积比2:3,本方法具有提取高、时间短、安全性高、成本低等优点,具有一定的实际应用价值。  相似文献   

4.
研究了用反相高效液相色谱法同时测定饲料中 VE和 VD3 的技术及试验溶液的皂化、提取、浓缩等试样前处理方法。选出了最佳色谱条件 ,流动相 :甲醇 +水 (95 +5 ) ,流速 :1ml/min,温度 :室温 ,进样体积 :2 0μl,检测波长 :2 64nm。  相似文献   

5.
杨先乐 《水产学报》2001,25(4):348-354
应用反相高效液相色谱法(RP-HPLC)建立了盐酸环丙沙星在中华绒螯蟹血淋巴内含量的测定方法.本法采用肌肉注射的给药方法,给药剂量为8.17±0.56mg·kg-1和6.25±0.85mg·kg-1.血淋巴从心区抽取.经各种抗凝方法的比较,认为等量的ACD与等量的血淋巴混合,可得到持久的抗凝效果.血淋巴样经甲醇去蛋白,3000r/min离心10min后,取上清液上HPLC.色谱柱,RP-ODS-5μl50×4.6mm;流动相,甲醇-磷酸缓冲液-四丁基溴化铵=25075020(v/v/v);流速,l mL·min-1;进样量,2μL;检测波长,280nm.研究表明,本法线性关系与重复性良好;雌、雄蟹平均回收率分别为100.08±3.43%和99.11±8.20%;日间精密度、平均提取精密度分别为1.19±0.92%、1.55±0.01%.用该方法对肌肉注射给药后48h内中华绒螫蟹雄蟹血淋巴中的盐酸环丙沙垡的血药浓度进行检测,揭示出由37.13±0.08μg·mL-1降至5.96±0.18μg·mL-1的代谢规律.  相似文献   

6.
液相色谱-串联质谱法测定水产饲料中喹乙醇残留量   总被引:3,自引:0,他引:3       下载免费PDF全文
为测定水产饲料中喹乙醇的残留量,建立了高效液相色谱-串联质谱的测定方法.水产饲料经5%甲醇溶液提取,HLB固相萃取小柱净化后上机定量检测.采用Zorbax XDB C18色谱柱,并以O.2%乙酸水溶液+甲醇(60+40,体积分数)为流动相,色谱分离后直接进串联质谱器.采用电喷雾正离子,多反应监测模式检测,外标法定量.在1~20 mg/L浓度下具有良好的线性关系,方法的定量限为0.04 mg,/kg,添加浓度在1-20 mg/kg时的回收率为72.2%~98.5%,相对标准偏差小于7.9%.  相似文献   

7.
喹烯酮在建鲤和斑点叉尾鮰体内的残留消除规律   总被引:2,自引:0,他引:2       下载免费PDF全文
研究了饲养条件下喹烯酮及其代谢物脱二氧喹烯酮在建鲤(Cyprinus carpio var.jia) 和斑点叉尾鮰(Ictalurus punctatus) 体内的残留消除规律。以含喹烯酮75 mg/kg的饲料,在池塘中饲喂60 d,于停饲后1、2、3、5、7、9、12、15 d分别将建鲤 (Cyprinus carpio var.jia) 和斑点叉尾鮰 (Ictalurus punctatus) 处死后取肌肉组织。组织样品用乙腈提取,正己烷脱脂等前处理过程。在320 nm 波长处检测,流动相为乙腈:甲醇:水(5:2:3,v/v/v),流速为1.0 mL/min。结果表明,喹烯酮平均回收率为75.4 %~80.5 % ;脱二氧喹烯酮平均回收率为74.5 %~79.1 %,喹烯酮和脱二氧喹烯酮的检测限分别为7.35 µg/kg,16.23 µg/kg。在饲喂结束后1~15 d采集的建鲤和斑点叉尾鮰肌肉样品中均未检测到喹烯酮及其代谢物脱二氧喹烯酮。因停药1 d后鱼体肌肉中喹烯酮及其代谢物浓度均低于计算所得的安全浓度,故喹烯酮用在水产养殖上是非常安全的。本试验为喹烯酮在水产养殖中的安全应用提供了理论资料。  相似文献   

8.
喹乙醇 (Olaquindox)又名倍育诺 (Bay On Ox)、喹酰胺醇、快育灵 ,属喹口恶啉类化合物 ,具有广谱抗菌、促进动物生长、提高饲料转化率的作用 ;同时又具有用量较少、价格便宜、不易产生耐药性等优点 ,故在畜禽养殖中得到广泛应用。主要用作饲料添加剂 ,一般推荐用量 :家畜 5 0~1 0 0 mg/g,家禽 2 5~ 3 5 mg/g、鱼类 5 0~ 80 mg/g[1 - 3] 。近年来 ,喹乙醇被作为抗菌促生长药物推广应用到水产动物养殖业 ,但喹乙醇的有效剂量与中毒剂量相差很小 ,尤其是在用户不了解喹乙醇有效成分含量的情况下 ,一旦操作失误 ,极易引发中毒事件。一、事…  相似文献   

9.
为了准确评估渔业生态环境中的孔雀石绿(MG)及其代谢产物隐性孔雀石绿(LMG)的残留状况,建立了3种渔业环境基质(水体、底泥和底泥-水体混合物)中MG和LMG的高效液相色谱-串联质谱(HPLC-MS/MS)检测方法。通过考察不同前处理方法对不同基质中MG和LMG回收率的影响,优化仪器性能,确定了色谱和质谱分析条件。具体方法是:水体过滤后采用PRS固相萃取柱进行净化、富集;底泥采用乙腈-二氯甲烷(1∶1,v/v)提取,再旋蒸、富集;底泥-水体混合物用二氯甲烷提取后,采用PRS固相萃取柱净化、富集。采用Thermo C18色谱柱对待测物进行分离,以乙腈-0. 2%乙酸铵(1∶1,v/v)为流动相洗脱,电喷雾-多反应正离子监测模式监测,内标法定量。结果表明,3种不同基质中的MG和LMG在1~8 ng/m L范围内线性显著,其相关系数r~2值大于0. 999;加标回收率分别为90. 0%~104. 2%、79. 9%~90. 3%和74. 1%~86. 3%,相对标准偏差为3. 3%~5. 8%、4. 9%~8. 6%和3. 2%~8. 3%; MG的检出限(LOD,S/N=3)分别为0. 24 ng/L、0. 02μg/kg和0. 06μg/kg,定量限(LOQ,S/N=10)分别为0. 79 ng/L、0. 07μg/kg和0. 21μg/kg; LMG的检出限(LOD,S/N=3)分别为1. 14 ng/L、0. 17μg/kg和0. 12μg/kg,定量限(LOQ,S/N=10)分别为4. 72 ng/L、0. 56μg/kg和0. 39μg/kg。该法可应用于渔业环境中MG及LMG的定性定量检测,具有较好的实用性。  相似文献   

10.
洛美沙星在鲤鱼体内的药物动力学及残留   总被引:3,自引:0,他引:3  
用高效液相色谱 (HPLC)测定方法研究洛美沙星在鲤鱼 (Cyprinuscarpio)体内的药物动力学和残留。洛美沙星以 2 0mg/kg体重单剂量口灌鲤鱼后 ,测定其血浆药物浓度 ,最低检测限为 0 0 5 μg/mL ,动力学模型符合开放性有吸收二室模型 ,药物动力学参数 :表观分布容积 (Vd/F)、吸收半衰期 (tl/ 2kα)、分布半衰期 (t1/ 2α)以及消除半衰期 (t1/ 2 β)分别为 5 2 1L/kg、 0 31h、 1 0 2h、 2 0 0 3h ,其药时曲线下面积(AUC)为 110 92 μg·h/mL。以相同剂量单次口灌鲤鱼后 ,在不同的天数测定了鲤鱼皮肤、肌肉和肝胰脏中洛美沙星的残留 ,在给药 12天后 ,洛美沙星在各组织中均能检测到且残留均低于 0 0 8μg/g ,结果表明洛美沙星在鲤鱼体内消除缓慢、残留期较长 ,休药期不低于 12天。  相似文献   

11.
Elevated carbon dioxide concentrations reduce feed intake and growth in several fish species and induce stress responses. In this study, the effects of moderately elevated CO2 levels on performance, energy partitioning, swimming activity and stress response in European seabass were assessed. European seabass (140.0 g) were reared under two levels of CO2 (1.6 and 7.0 mg L?1) and two feeding levels (FLs) (maintenance and satiation) for 60 days, and fish swimming speed was recorded. At the end of the experiment, fish were subjected to an acute stress test. Blood cortisol, glucose and lactate were analysed. Energy and nitrogen balances were quantified based on measurements of body composition and digestibility coefficients. Moderately elevated chronic CO2 level did neither affect energy requirements for maintenance nor the utilization of digestible energy for growth. However, swimming activity data suggests that FL dependent alterations in energy partitioning took place. Blood cortisol values after the acute stress were affected by additional CO2 exposure and this effect was also dependent on FL. The elevated CO2 exposure of 7.0 mg L?1 appears to act as a chronic stressor as adaptive responses took place, however, this CO2 exposure seems to be still within the allostatic load of the fish.  相似文献   

12.
2019年5月、8月和11月,在上、中、下游共设5个采样点,采用单层刺网(网目1、2、3 cm,网长20、30、40 m)和地笼网(开口40 cm×40 cm,长8 m)调查新疆天山南麓中段塔里木河流域九大水系之一的渭干河(N 41°06′~42°42′,E 80°40′~84°10′)的鱼类资源状况。调查共采集鱼类1864尾,总质量47869.05 g,隶属3目6科15属19种。土著鱼类1目4属8种,其中鲤科鱼类3属5种,鳅科鱼类1属3种。外来鱼类3目11属11种,其中鲤科鱼类6属6种,鳅科、鲈科、塘鳢科、虾虎鱼科、鲇科各1属1种。8月捕获鱼类种类最多,共17种。5月捕获渔获物数量和质量最大,占总渔获物数量的38.41%,占总渔获物质量的64.12%。渭干河优势种为斑重唇鱼、、河鲈和麦穗鱼。渭干河上游、下游河段鱼类种类稀少,群落多样性低。与历史数据相比,扁嘴裂腹鱼和重唇裂腹鱼未采集到,其他土著鱼类捕获量低,外来鱼类捕获量大。通过聚类分析,将5个采样点鱼类分为2类,经过单因子相似性分析得出,这2个群聚之间差异不显著(P>0.05)。将渭干河4种优势种和8种常见种分为2类,经过单因子相似性分析得出,这2个群聚之间差异显著(P<0.05)。外来鱼类入侵和水利工程是影响渭干河鱼类群落的主要因子。  相似文献   

13.
Between 2007 and 2012, a variety of disease outbreaks most often characterized by skin disorders were observed among different species of freshwater fish in Poland. In most cases, the clinical signs included focally necrotized gills, necrotic skin lesions or ulcers. Internally, haemorrhages, oedematous kidney and abnormal spleen enlargement were generally noted. The disorders were accompanied by increased mortality. Most of the problems concerned cultured common carp Cyprinus carpio L. and rainbow trout Oncorhynchus mykiss (Walbaum). Fish have been examined from a number of these farms, and additionally, the wild and ornamental fish with similar clinical signs of diseases were also tested. Bacteria were isolated consistently from lesions and internal organs. They had characteristic orange-pigmented colonies which grew in pure culture or constituted 55–95% of total bacterial flora. One hundred and eighteen isolates were collected and biochemically identified as Shewanella putrefaciens group, and this was confirmed by sequencing. Challenge tests confirmed the pathogenicity of these bacteria. This is the first report characterizing and describing S. putrefaciens as a pathogen of different species of freshwater fish in Europe.  相似文献   

14.
ABSTRACT

The current practice of fish processing generates large amounts of by-products, which can account for up to three-quarters of the total fish weight. Despite the presence of several valuable components in the fish processing discards, the latter are usually dumped into landfills or at sea, having potentially harmful environmental effects or end up as low commercial value products (e.g., white fish meal). Still, fish processing by-products can be considered as an alternative raw material for the preparation of high-protein ingredients, especially for the production of food grade gelatin due to the presence of large amounts of collagen in fish skins, scales, and bones. Although fish gelatin is an alternative to the commercially available mammalian gelatins, its production on a large commercial scale has been hampered, mainly, due to the inferior quality characteristics compared to its mammalian counterparts. This review article summarizes and highlights the potential utilization of by-products generated during fish processing for gelatin extraction. Furthermore, several technical challenges and directions of ongoing research are discussed.  相似文献   

15.
16.
Aquaculture is one of the fastest growing food producing sectors in the world. The increase in the world population requires faster growth in aquaculture for better food availability and to overcome malnutrition. But this worldwide growth of aquaculture is overwhelmed by catastrophic fish diseases and spoilage during cultivation and preservation problems caused by pathogenic bacteria. Various remedies are available for food preservation and also from the bacterial diseases in the fish production. Due to the emergence of antibiotic resistance and adverse effects, an alternative to antibiotic is the need of the hour. The proteins such as bacteriocins, i.e. ribosomally synthesized antimicrobial peptides (AMPs) and possess antagonistic against closely related and other bacteria. These proteins are produced by most lineages of bacteria which are playing key roles in recognition and possess a cognate immunity system for self‐protection as well as host protection from infections. These proteins are potent immunomodulators with broad spectrum inhibition properties which are further used as novel therapeutic agents. In this review, we have tried to summarize the bacteriocins on the basis of their classifications, structural and functional attributes, mode of actions, bacteriocins isolated from fish and gut microbiota and presence of beneficiary bacteria in the fish gut. Further, this study highlighted where further research is a prerequisite to increase our basic understanding and search for novel bacteriocins to elucidate the proteins/peptides having antimicrobial properties for disease control in aquaculture as an alternative to antibiotics.  相似文献   

17.
Abstract  Substantial alterations to the legal controls over fish movements have been necessary to implement the Single European Market which came into force on 1 January 1993. This seeks to liberalize trade in fish and fish products whilst avoiding ecological damage, the spread of disease and the commercial damage this may cause. The new regime governing fish movements into and within the European Union under Directive 91/67/EEC, as implemented in England and Wales, is described. Remaining national provisions based on ecological concerns (principally, section 30 of the Salmon and Freshwater Fisheries Act 1975) are examined. Derogations from the principle of freedom of trade within the European Union on environmental protection grounds are assessed, and the interaction between legal restrictions based on pathological and ecological grounds is discussed.  相似文献   

18.
The effect of single and double freezing at ?20°C on fresh and aged red hake with two different holding times of the thawed fillets between the first and second freezing treatments was determined. In addition, twice-frozen fresh red hake was treated with two antioxidation systems to assess their effectiveness in reducing lipid oxidation. Fresh, untreated red hake at 0 time was used for comparison. Significant dimethylamine (DMA) production occurred with all frozen samples, and the differences were not marked after 7-month storage. With a storage time of 3 months, however, there were differences between the treatments in both the fresh and aged samples with the once-frozen sample producing the least DMA, the twice-frozen sample with the 24-h holding time between freezings the most, and the twice-frozen sample with a 6-h holding time between freezings giving intermediate values. All samples showed a greater than 50% loss in protein solubility as determined by lithium chloride extraction after 3 months of storage, and the protein solubility declined further when samples were tested at 7 months. Samples with the best (once-frozen fresh) and worst (twice-frozen with 24-h holding time between freezings of 5-day aged muscle) treatments had the highest thiobarbituric acid-reactive substances (TBARS) values. Both antioxidant treatments were effective in reducing TBARS development.  相似文献   

19.
Hydropower‐related damage to fish remains a great challenge, making objective monitoring of turbine‐related fish injury a necessity. The catch of fish at turbine outlets is currently realised by net fishing, but potential catch‐related injuries are largely unknown. Catch efficiency and fish‐friendliness in relation to fish handling, exposure time, floating debris and fish biomass of four fish recovery installations were assessed using seven species. Highly species‐specific lethal and sublethal effects were observed. Exposure time had the strongest effects on catch‐related damage, being up to 150‐fold increase after 12 hr compared to 1 hr. Up to 84% mortality occurred in the most sensitive species Thymallus thymallus L. Besides exposure time, higher current speed and biomass within the net resulted in greater fish damage. To minimise catch‐related effects, keeping emptying periods <1–2 hr and considering the effects of current speed, fish and debris biomass are crucial to increase data comparability among studies.  相似文献   

20.
淡水鱼在保温鱼箱中贮存期限的研究   总被引:5,自引:0,他引:5  
沈月新  张钟兴  欧杰 《水产学报》1990,14(2):160-164
我国养殖淡水鱼类居世界首位。特别是近年来淡水鱼的产量迅速增长,淡水鱼从生产到流通上市过程中的保鲜问题日趋重要。以往淡水鱼的贮运除活鱼车运输外,大多采用传统的木桶、竹篰、蒲包等落后的包装容器,由于保温条件差,鱼体受挤压,鱼货容易腐败变质。保温鱼箱是近年来渔业生产上使用的新型包装容器,从目前使用于海水鱼的情况来看,它具有良好的保鲜效果。为了进一步开拓保温鱼箱在淡水鱼流通领域中的应用,我们选用了上海市水产供销公司研制的8B-3型塑料保温鱼箱,以养殖  相似文献   

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