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草鱼出血病是由草鱼呼肠孤病毒(Grass carp reovirus,GCRV)引起的严重危害1~2龄草鱼的一种传染性疾病。本研究从安徽合肥地区患典型草鱼出血病的病鱼组织中分离到1株新的GCRV致病株,暂命名为GCRV-AH528。鱼体人工感染实验结果显示,实验鱼出现典型的出血病症状:体背发黑,鳍基部、腹部、口腔、鳃丝、肠道充血发红。全基因组特征分析显示,GCRV-AH528由11个双链RNA节段组成,节段大小在1027~3925 bp之间,AT平均含量为50.2%,GC平均含量为49.8%。与其他GCRVⅡ型毒株相比,L1节段在701~702位置缺少3个核苷酸(TAT),少编码1个酪氨基;M4节段出现突变,含2个开放阅读框,编码2个非结构蛋白NS9和NS69。所有节段两端均含有6 bp保守的末端核苷酸序列5'-GUAAU/CU…UU/GCAUC-3';另除L1、M6节段外,其余9个节段均在编码区两侧发现5~9 bp的颠倒互补序列。GCRV-AH528与其他呼肠孤病毒核苷酸平均相似度在37.1%~98.1%之间;编码蛋白平均相似度在24.3%~98.3%之间。基于VP1蛋白的聚类分析结果显示,该病毒属于水生呼肠孤病毒属,在氨基酸水平上与典型株GCRV-873株的进化关系较远。本研究结果表明,该毒株为一株新的草鱼呼肠孤病毒Ⅱ型致病株。 相似文献
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为研究甲壳素发酵液对草鱼和鲢鱼幼鱼养殖效果,用商品壳聚糖作参比,基础饲料为对照组,分析甲壳素发酵液对鱼体生长和水质环境等影响。试验结果表明,甲壳素发酵液处理组草鱼和鲢鱼幼鱼质量相对增长率比对照组高36.25%和122.47%(P0.05),草鱼体内脂肪酶、蛋白酶和淀粉酶3种消化酶分别比对照组高144.39%、29.53%和29.75%,鲢鱼体内消化酶比对照组高48.06%以上(P0.05)。与对照组比较,甲壳素发酵液显著降低水中亚硝态氮(61.84%)、氨态氮(30.06%)、总磷含量(52.43%),提高了草鱼对嗜水气单胞菌抗性。在试验条件下,甲壳素发酵液对草鱼和鲢鱼幼鱼起到一定的促生长作用,并能改善水质环境,甲壳素发酵液具有作为微生态制剂开发应用的潜力。 相似文献
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Jirawat Yongsawatdigul Saowanee Pivisan Wasana Wongngam Soottawat Benjakul 《Journal Of Aquatic Food Product Technology》2013,22(5):460-473
Small-scale mud carp (SC, Cirrhina microlepis) and common carp (CC, Cyprinus carpio) are underutilized freshwater fish. The objective of this study was to elucidate the gel-forming ability of mince and washed mince from these species in relation to washing cycles and CaCl2 addition. Protein loss of up to 67% was observed after three-washing cycles of both species, rendering relatively low yield. About 85–90% of total fat was removed from SC flesh after three-washing cycles, but only two-washing cycles were sufficient for fat removal in CC mince. Mince and washed mince of both species did not exhibit severe proteolysis with low autolytic activity at 65°C. SC exhibited superior gel-forming ability to CC. Two- and three-washing cycles in conjunction with a 40°C-preincubation resulted in the highest textural properties of SC and CC, respectively. CaCl2 increased the breaking force of CC and SC mince gels up to 65 and 95% at 0.3 and 0.5% CaCl2, respectively, as compared to without CaCl2. However, it showed negative effects on surimi gels of both species. Both SC and CC are potential freshwater fish resources for mince and washed mince production with reasonable good gel-forming ability. 相似文献
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为进一步提高我国广大池塘养鱼的产品质量、经济效益和改善其生态环境。本试验在武汉新洲973项目实验基地9个陆基鱼池中进行了三种不同混养模式鱼类生长和效益的比较研究,每种模式设3个重复。模式Ⅰ中放养草鱼、鲢、鳙和高背鲫;模式Ⅱ中放养草鱼、鲢、鳙、匙吻鲟和高背鲫;模式Ⅲ中放养草鱼、鲢和高背鲫。
结果表明:通过122d的养殖试验,模式Ⅱ中草鱼的生长不仅显著高于模式Ⅰ和模式Ⅲ(P<0.05),而且其经济效益模式Ⅱ同样高于模式Ⅰ和模式Ⅲ。 相似文献
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以枯草芽孢杆菌为主的主要用于促进鱼类消化生长的微生态制剂I、多种混合微生物主要用于调节水质的微生态制剂II,或是两者混合使用的方法,比较研究了黑龙江省及辽宁省池塘养殖的鲤(Cyprinus carpio)、鲫(Carassius auratus)和草鱼(Ctenophyargodon idellus)的增重率、饲料系数及药价等效益。结果表明,单种或者混合使用微生态制剂均对池塘养殖鲤及草鱼的增重率、饵料系数及用药价格有一定影响,同时使用两种微生态制剂提高鱼类增重率最显著,辽宁省和黑龙江省分别提高了423.57%和90%;而两省养殖池塘的药价也分别降低了29%和56.25%。微生态制剂I及混合同时使用两种微生态制剂均能显著降低饲料系数,辽宁及黑龙江分别降低0.35及0.05。结果可见,适当使用微生态制剂对辽宁草鱼及黑龙江池塘养鲤效益有较好影响,对减少用药、发展绿色养殖业具极大的推动作用。 相似文献
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阳澄湖3个湖区鲢鳙控藻效应的比较研究 总被引:1,自引:0,他引:1
阳澄湖是江苏省重要的淡水湖泊之一,全湖分为东、中、西3个湖区。近年来阳澄湖内加大了鲢(Hypophthalmichthys molitrix)、鳙(Aristichthys nobilis)的控藻力度,西湖藻华消失,而中湖和东湖仍偶有藻华出现。为了比较不同湖区水质和浮游植物的差异,在3个湖区分别布设南、北2个采样位点,于2017年夏季、秋季及2018年春季采集水样进行鲢鳙控藻效应分析。结果表明,阳澄湖3个湖区总氮(TN)、总磷(TP)均达到劣Ⅴ类水质标准,营养盐浓度由西向东逐渐下降。西湖3个季节叶绿素a(Chl-a)浓度都低于15μg/L,透明度最高。调查期间共发现浮游植物8门、77属、177种,其中西湖种类数最少,仅有8门、59属、105种。从浮游植物多样性看,阳澄湖水质处于轻污染状态。西湖浮游植物细胞密度年均(3.50±0.49)×10~6个/L,分别约为中湖和东湖的1/10和1/4。中湖和东湖于夏、秋季检出超富营养化(ɑ-ps)指示藻类,但西湖三季均未检测到。2017年10月,西湖鲢鳙存鱼密度分别为中湖的3.8倍和东湖的2.3倍,规格和肠道饱满度指数显著低于中湖和东湖(P0.05)。研究显示,现阶段阳澄湖藻华发生与否不完全由营养盐水平决定,可能还与鲢鳙牧食藻类有关。 相似文献
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不同地域黄河鲤、建鲤肌肉生化组成的比较研究 总被引:1,自引:0,他引:1
《水产科学》2015,(9)
为给黄河鲤肉质改良研究提供科学依据,分别采集了陕西新民家鱼原种场、河南郑州黄河鲤鱼良种场养殖黄河鲤和伊洛河花园口段野生黄河鲤,并与养殖范围较广的建鲤品种(采自辽宁丹东英波鸭绿江生态科技股份有限公司)作了比较分析。应用生化分析方法对4个鲤群体肌肉中的基本营养成分、氨基酸含量以及脂肪酸含量进行了分析。分析结果表明,各群体之间水分和灰分的差异不显著(P0.05),黄河鲤群体的粗脂肪含量除郑州良种场群体外,均显著低于建鲤群体,陕西群体的粗蛋白含量显著高于其他3个鲤群体(P0.05)。陕西群体的总氨基酸、总必需氨基酸和总呈味氨基酸均最高,必需氨基酸含量为陕西群体伊洛河群体建鲤群体郑州良种场群体。建鲤群体的必需氨基酸指数最高,平均为90.11。郑州良种场群体的单不饱和脂肪酸含量最高,建鲤群体多不饱和脂肪酸含量最高,而不饱和酸总量最大的为陕西群体,必需脂肪酸最大的为伊洛河群体。以氨基酸评分和化学评分进行评价4个鲤鱼群体的第一限制性氨基酸均为缬氨酸,氨基酸评分第二限制性氨基酸均为异亮氨酸,化学评分第二限制性氨基酸均为甲硫氨酸+半胱氨酸。 相似文献
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对无水乙醇提取草鱼内脏鱼油工艺进行了研究,并分析了鱼油的基本理化性质和脂肪酸组成,主要研究了料液比对鱼油提取率的影响。无水乙醇提取草鱼内脏鱼油的工艺为:料液比(w:v)1:8,提取温度55℃,提取时间3小时。在此工艺条件下,粗鱼油提取率为87.6%。粗鱼油经85%磷酸脱胶、4%NaOH脱酸、活性白土脱色后,鱼油呈浅黄色透明状,酸价、过氧化值较低;经冬化处理后的鱼油中不饱和脂肪酸含量约为81.5%。 相似文献
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ABSTRACTFish is one of the most common sources of food allergens, and grass carp is among the most popular freshwater fish. The objective of this study was to investigate the effects of heat treatment on the antigenicity and allergenicity of white and dark muscle of grass carp. The results showed that the antigenicity of heated white muscle was higher than that of unheated white muscle, while the allergenicity of white muscle was lower than that of unheated muscle when heated at 65°C, and the lowest value was 44.6%. Furthermore, the allergenicity of dark muscle increased for the first 30 min when heated at 65°C, and it increased for the first 60 min and then decreased with the increasing heating time thereafter when heated at 80 and 100°C. In addition, the lowest antigenicity and allergenicity of dark muscle were obtained at 100°C, and the values were 0.447 mg mL?1 and 47.0%, respectively. Thus, to decrease the antigenicity and allergenicity of grass carp muscles, it is suggested that heating at 65°C is better than 80 or 100°C for the white muscle, while 100°C is an appropriate heating temperature for the dark muscle. 相似文献
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Liwei Liu Yuliang Luo Xu‐Fang Liang Weimin Wang Junjie Wu Jing Pan 《Journal of the World Aquaculture Society》2013,44(1):56-65
Two 8‐wk studies were conducted to evaluate the effects of neutral phytase supplementation on hemato‐biochemical status, liver biochemical parameter, and intestinal digestive enzyme activity of grass carp, Ctenopharyngodon idellus, and gibel carp, Carassius auratus gibelio, fed with different levels of monocalcium phosphate (MCP). The control diet was prepared with 2% MCP but without phytase (P2.0). The other three experimental diets were prepared with the addition of 1.5, 1.0, and 0.5% MCP, respectively, when supplemented with 500 U/kg neutral phytase in each diet and designated as PP1.5, PP1.0, and PP0.5, respectively. The results indicated that the serum alkaline phosphatase (ALP), alanine transaminase (ALT), and aspartate transaminase (AST) activities, as well as the albumin (ALB) content were increased in grass carp (P < 0.05) and gibel carp (P > 0.05) fed with phytase‐supplemented diets. Meanwhile, the serum cholesterol, high‐density lipoprotein, and total protein contents of the two species of fish were increased in comparison to the control. In addition, dietary phytase inclusion did not significantly affect hepatic ALP, ALT, and AST activities in the two species of carp fed with different levels of MCP. Amylase activity increased in foregut and hindgut of both species when fed with the phytase‐supplemented diets while lipase activity was reduced in the foregut and hindgut in both fish. This study suggests that neutral phytase supplementation increases serum ALP, ALT, and AST activities but does not notably affect these enzyme activities in the liver of the two species of carp when fed different levels of MCP. On the other hand, amylase activity increased while lipase activity was reduced in the intestine of the species of carp fed with phytase‐supplemented diets. 相似文献