鲟鱼软骨对小鼠生长及肝损伤的保护作用研究

鲟鱼软骨按0%、1%和3%的添加比例制成3种试验饲料.用健康的雄性昆明小白鼠为实验对象,分别进行4周的生长试验和CC l4染毒试验.CC l4染毒试验于28 d时,对照组腹腔注射精制豆油,其余各组以10 mL.kg-1剂量注射0.2%CC l4精制豆油溶液造成肝损伤,36 h后眼眶取血测定转氨酶活性,并取肝、脑、睾丸,测定超氧化歧化酶(SOD)活性、Na+,K+-ATP酶活性、总抗氧化值(T-AOC)、丙二醛(MDA).小鼠生长试验结果表明,软骨组小鼠体增重增加、耗料增重比降低及组织系数变化均与对照组没有明显差异(P>0.05).但软骨组小鼠血浆AST活性显著升高(P<0.05).小鼠CC l4染毒试验结果表明,与CC l4肝损伤组比较,软骨组小鼠肝、脑和睾丸组织中的Na+,K+-ATP酶活性、SOD活性、T-AOC值呈不同程度的升高,而MDA含量则呈不同程度的降低,但差异不明显(P>0.05).提示,鲟鱼软骨能够对小鼠的生长代谢产生影响并对CC l4所致小鼠肝损伤有一定的保护作用.     

饲料中D-葡萄糖含量对白鲟稚鱼的生长、脂肪合成酶及肝组成的影响

以不同含量的D-葡萄糖(0%,7%,14%,21%,28%和35%)饲料饲喂白鲟稚鱼8周.7%以上各组的能量贮留和体脂含量均显著高于0%实验组,但机体的蛋白组成及贮留却不受此处理影响.饲料中D-葡萄糖含量的增加,导致稚鲟的血糖、血浆三酰甘油脂以及4种主要肝脂肪合成酶活性的提高.28%和35%两组的肝脂肪合成酶活性比0%和7%两组要大2—3倍.肝体指数、肝重及肝糖元水平均随饲料中D-葡萄糖含量的提高而逐渐增加,饲喂葡萄糖饲料各组的肝糖元水平均显著高于0%组2倍以上.     

由长江中的三种鲟到长江水域生态保护

通过系统整理长江中三种鲟与长江水域生态保护文献的基础上，描述了这三种动物的生物学特征，梳理了白鲟灭绝、中华鲟与长江鲟极度濒危的历程.从长江水域生态保护的角度，分析了导致长江生物多样性严重下降的因素，包括水利工程、酷渔滥捕、水质污染、航运与采砂等人类活动.针对性地提出了8个方面的保护对策：实施生态修复、十年禁渔、加强保护区建设、生态调度、控制水污染、加强监测和研究、健全生态补偿机制、建设国家级保种基地.     

Review of sterlet (Acipenser ruthenus L. 1758) (Actinopterygii: Acipenseridae) feeding habits in the River Danube, 1694–852 river km

The aim of this work is to present the variation in the sterlet’s (Acipenser ruthenus L. 1758) diet along the course of the River Danube, from 1694 to 852 river km. The diet of sterlet mostly comprised 12 bottom fauna taxa. Sterlet in the Danube feed mainly on larvae of Trichoptera, Chironomidae (Diptera) and Gammaridae (Amphipoda), with a reduction in food composition variability close to the Djerdap I dam and in the reservoir between the two dams. The other components of the diet were Corophium sp., Asselus sp., Mollusca, Oligochaeta, Annelida, Insecta, Nematoda and Hirudinea. The organisms typical of lithorheophilic and psammorheophilic biocoenoses play a considerable role in the diet of the sterlet. Composition of bottom fauna as food items varies due to changes in environmental conditions induced mainly by the construction of two dams: Djerdap I (943 river km, 1970) and Djerdap II (863 river km, 1984).     

鲟源豚鼠气单胞菌分离与强弱毒株病原生物学比较研究

从患慢性出血败血综合症的杂交鲟和达氏鳇病鱼标本中分离到一株优势菌,优势率80%,经回感和重分离确定为致病菌,并经生理生化和16SrDNA检测为豚鼠气单胞菌,命名为ZZF071029（简称ZF1029）,以豚鼠气单胞菌弱毒株ZF1029和强毒株XL2-T为研究对象,进行了菌落形态学、运动性实验、溶血性实验、小鼠致死试验、角膜毒力实验、药物敏感性实验等病原生物学相关实验。实验结果证明,病原菌运动性、溶血性、小鼠致死力、角膜毒力与菌株毒力和致病力正相关,并与所致杂交鲟和达氏鳇出血败血综合症急、慢性程度和致死率一致。     

长江及珠江鲟鱼形态特征的初步比较

鲟鱼是我国具有重要经济价值和学术意义的鱼类,我国曾报导长江内有两种,珠江内有一种.迄今有不少学者将我国长江水利枢扭修建后的主要救鱼对象报导为中华鲟(Acipenser sinensos Gray),本文初步比较了珠江内中华鲟的地模标本和长江内的鲟鱼的形态同分类性状,发现它们之间在八项特征上有明显的差异,差异程度已达种一级的水平,因而提出长江内的中华鲟的记录是一个值得商讨和重新考虑的问题.     

三峡水库水温变化及其对中华鲟繁殖的影响

分析了三峡库区相关水文站建库前后的水温变化规律,利用水库热量平衡方程计算了三峡水库下泄水温的“滞温”和“滞冷”幅度,并对下泄水温变化对坝下中华鲟繁殖的影响进行了研究.结果表明,三峡水库围堰发电期库区近坝段主槽没有出现水温分层现象,下泄水温“滞温”和“滞冷”现象较轻,葛洲坝下10月份水温生态因子演变为中华鲟产卵场繁殖的限制因子.     

Primitive actimoterigian fishes can synthesize ascorbic acid

Amphibians and reptiles evolved with the capacity to synthesize ascorbic acid. Some higher vertebrates, like bats, guinea pigs, primates, and humans have lost the microsomal enzyme gulonolactone oxidase, and in cases of ascorbic acid deficiency suffer from symptoms of scurvy. The question of whether the capacity to synthesize ascorbate is also present in lower vertebrates could throw light on the evolution of this pathway. In order to find out whether ascorbic acid synthesis took place in two primitive Actinopterigian fish, the paddlefish (Polydon spathula) and the white sturgeon (Acipenser transmontanus) were fed with a scorbutogenic diet or diet(s) supplemented with a graded level of ascorbic acid. We found no growth depression nor external symptoms of scurvy, which would be pronounced in modern bony fishes (Teleostei) under similar conditions. The tissue level of ascorbate in both these primitive species indicated that vitamin C in intestine and liver is not depleted when fed a scorbutogenic diet. Gulonolactone oxidase activity was found in the kineys of the Actinopterigian fishes. Thus, I question the accepted evolutionary pathway for ascorbic acid biosynthesis in lower vertebrates and suggest that the modern bony fishes,Teleostei, lost their ability to express the gulonolactone oxidase genes after they had separated during the Silurian from their common ancestor with the coelacanths (Latimeria) and Dipnoi.     

流水养殖条件下养殖密度对俄罗斯鲟幼鱼非特异性免疫的影响

【目的】为了给俄罗斯鲟鱼(Acipenser gueldenstaedti)养殖管理提供借鉴,研究流水养殖系统中不同养殖密度对俄罗斯鲟幼鱼非特异性免疫的影响。【方法】选取初始体重为(29.70±1.32)g的俄罗斯鲟幼鱼分置于2.5kg/m~3(SD1)、3.6kg/m~3(SD2)和4.7kg/m~3(SD3)3个养殖密度进行流水池塘(4.4m×4.4m×0.45 m)养殖,每个密度设3个重复,实验周期为90d。【结果】SD3组幼鱼超氧化物歧化酶(SOD)活性显著低于SD1组和SD2组(P0.05),表明较高的养殖密度打破机体抗氧化系统的平衡,抑制机体抗氧化功能的发挥。SD3组幼鱼丙二醛(MDA)含量显著高于SD1组、SD2组(P0.05),这是脂质过氧化反应增强,脂质过氧化产物增多的表现。随着养殖密度增加俄罗斯鲟幼鱼谷草转氨酶AST和谷丙转氨酶ALT活性逐渐升高,肝体指数降低。SD3组俄罗斯鲟幼鱼脾脏系数显著低于SD1、SD2组水平(P0.05),血液溶菌酶活性以及C3补体因子含量也显著降低。【结论】过分提高养殖密度,将会导致俄罗斯鲟幼鱼出现拥挤胁迫,使机体的自由基"稳态性动态平衡"遭受破坏,影响机体的正常生理状态,肝脏和脾脏均受损,免疫功能也受到一定程度的抑制,且随养殖密度增加抑制效应愈加严重。