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鱼类基因分子生物学及转基因鱼研究进展↑(*) 总被引:4,自引:0,他引:4
真核基因分子克隆技术的建立,提供了从核苷酸水平了解鱼类基因结构的手段。鱼类基因的分子克隆始于八十年代初、中期对虹鳟(Salmogairdneri)鱼精蛋白基因[52]和美洲黄盖鲽(Psendopleuronectesamericanus)抗冻蛋白(AFP)基因[22]的分子克隆,随后扩展到其他极地鱼类AFP基因,接着扩展到鱼类生长激素(GH)基因、催乳激素(PRL)基因、生长催乳素(somatolactinSL)基因等数十个基因。对这些控制鱼类重要生理机能的基因结构的认识,无论在理论上还是在渔业… 相似文献
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日本鳗鲡仔鱼摄食机理及其营养策略 总被引:2,自引:1,他引:2
鳗鲡属(Anguilla)鱼类共有19种和亚种,其中以欧洲鳗鲡(A.anguilla)和日本鳗鲡(A.japonica)最为重要。鳗鲡属鱼类发育需经历奇特的柳叶状仔鱼(leptocephaluslarva)阶段,其人工育苗技术是一道世界难题。柳叶状仔鱼现象仅见于真骨鱼类最原始的一个类群海鲢总目Elopomorpha(鳗鲡目Anguilliformes,海鲢目Elopiformes,背棘鱼目Notacanthiformes)。有关柳叶状仔鱼的发育策略,已从形态学、生理学及生物化学等方面进行了不少研究,但柳叶状仔鱼… 相似文献
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鳗鲡脂肪酸组成和胆固醇含量分析 总被引:1,自引:0,他引:1
对日本鳗鲡(Anguilla japonica)、欧洲鳗鲡(Anguilla anguilla)及其制品烤鳗进行胆固醇、脂肪含量和脂肪酸组成分析。结果表明,鳗鲡的胆固醇含量与其他鱼类接近,日本鳗鲡和欧洲鳗鲡及其烤鳗制品的胆固醇质量比分别为0.852、0.832mg/g和1.15、1.12mg/g。鳗鲡各食用部位中除腹部的胆固醇较高外,其他部位没有明显差异。鳗鲡的脂肪质量分数16%-24%,日本鳗鲡和欧洲鳗鲡高度不饱和脂肪酸质量分数分别为18.9%和19.0%,EPA DHA质量比分别为22.66mg/g和29.27mg/g。 相似文献
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硫酸铜对三角帆蚌肝脏和鳃的毒害 总被引:12,自引:2,他引:10
硫酸铜常用于淡水珍珠养殖中的蚌病防治[张元培1994],铜是生物体的必需微量元素,但当其浓度超过机体调节范围时,在体内累积过多,将会引起机体的酶活性[Zervas等1990]、生化成分[Sathyanathan等1988]、免疫系统[Kucharz和Sierakowski1988]等方面的一系列变化,对其生长、生存造成危害[Ewing等1982]。一般认为肝脏是解毒的器官,而鳃与水体外环境和机体内环境接触密切,也常被作为水生生物铜毒害的重要研究对象,但多集中在海洋生物[Miller和Mackay… 相似文献
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鳖白斑病和白点病是稚鳖期危害最为严重的疾病,且常并发、多见背部白斑、腹部白点的病灶、导致大量死亡,最高死亡率达90%以上。1994年北京某鳖场因该病发生稚鳖死亡2/5.经济损失40万元;同年沙市一稚鳖温室养殖场.由于该病造成稚鳖死亡90%以上;1995年此病全国大流行,1996年流行鳃腺炎病,1997年流行白底板病。1998年白斑病和白点病又有抬头趋势。驯养开食后20~60天发病率最高,体长10cm以上的幼鳖较少因此病死亡。1白斑病1.1白斑病的病原与诊断病原为毛霉菌(Mucorsp.),属真菌… 相似文献
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在 2000年度鳗鲡养殖过程中,病害发生频繁,尤其是一些危害重大疾病的大面积流行,给养殖生产者带来了严重的经济损失,另外,一些新疾病的出现及病原体耐药性的产生,更给疾病的处理带来了困难,本文就上述问题作总结探讨。 一、鳗鲡狂游性死亡症 本症为欧洲鳗鲡养殖过程中危害最为严重的疾病,在养殖鳗鲡仅发现于欧洲鳗鲡及美洲鳗鲡,日本鳗鲡不发生。在生产实践中发现,本症传染性极强,因而认为具病原体,而且病原体对寄主有较高的选择性。有关本症的病原体,大多研究认为与病毒有关,迄今发现的病毒有类冠状样病毒、弹状病毒… 相似文献
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实验选用4种鱼类传代细胞,对首次发现的鳗鲡“狂游病”的病原-鳗鲡冠状病毒样病毒进行了细胞分离与培养。本研究在鲤上皮乳头状瘤细胞中复制了鳗鲡冠状病毒样病毒粒子,并经病毒细胞培养物的电镜负染和超薄切片法检查得到了证实。 相似文献
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近年来,用来源广泛的大豆制品(豆粕、全脂豆粉、大豆蛋白)替代水产动物饲料中鱼粉作为蛋白源的研究已成为有关学者关注的热点。Shimeno等[1995]分别用生豆粕、熟豆粕、熟化全脂豆粉、膨化豆粕、大豆浓缩蛋白、大豆分离蛋白、大豆酶解蛋白替代红鱼粉对进... 相似文献
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鳗鲡仔,幼鱼年龄生长的研究 总被引:3,自引:0,他引:3
辽东半岛黄海北部沿岸河口4—6月溯河的白仔鳗,全长53.5—64.5毫米,平均58.83毫米,体长频率高峰位于57.1—59.0 毫米体长组,其体长体重呈直线相关。白仔鳗与幼鳗群体的体长、体重则是指数相关,其方程为W=1.136×10~(-7) L~(3.3871)。12尾白仔鳗耳石平均日轮数为146.3,据此对其产卵期进行了推测,观察证实,在不同生态条件下生活过的幼鳗耳石的环纹有过渡带存在。 相似文献
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鳗苗生态适应力的初步研究 总被引:3,自引:0,他引:3
体长56.1~67.0毫米,重0.092~0.182克的鳗苗在12~18℃水温条件下的耗氧率为0.073~0.475毫克/克·小时,对±5℃和±8℃的骤变水温无异常反映;从淡水中转入2.5%食盐水中经46小时正常,转入3.5%食盐水中9.5小时全部死亡;在PH5.5~9.5淡水中经72小时安全,PH10.0经72小时50%死亡;在淡水中饥饿忍受力最长达90余天。 相似文献
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辽东半岛(黄海北部)溯河鳗苗食性的初步研究 总被引:3,自引:0,他引:3
本文研究了溯河白仔鳗的食性,内容包括摄食消化器官的形态构造、食物组成、摄食频率和摄食强度、对食物的选择性和食性特征分析。 相似文献
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Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 下载免费PDF全文
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
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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