斑马鱼原肌球蛋白基因克隆表达及免疫学鉴定

克隆斑马鱼原肌球蛋白的基因并表达纯化出重组蛋白,对其免疫学特性进行鉴定。提取斑马鱼总RNA,采用RT-PCR克隆斑马鱼原肌球蛋白的全长基因,根据序列设计带有酶切位点的特异性引物,扩增斑马鱼原肌球蛋白基因的完整开放阅读框,连入载体pET-28a,在大肠杆菌BL21(DE3)菌株中通过IPTG诱导得到重组斑马鱼原肌球蛋白。重组蛋白经Ni 2+亲和层析柱纯化后进行Western-blot检测。获得斑马鱼原肌球蛋白基因,Western-blot结果显示重组蛋白具有良好的免疫活性。本研究成功克隆并表达了斑马鱼原肌球蛋白基因,经免疫学鉴定发现其具有过敏原性。     

Reproductive characteristics and variations in the biochemical composition of Neptunea arthritica cumingii crosse through embryonic development

The copulation, egg laying, embryonic development and changes in amino acids and fatty acids in Neptunea arthritica cumingii during embryogenesis were studied to understand the embryo development process and nutritional requirements in the early life phase. The results showed that N. arthritica cumingii has direct development within the egg capsule and the development of embryos was classified into five stages: cleavage, egg swallowing, protoconch forming, shell development and juvenile. Embryos develop through the provision of nurse eggs as an extra‐embryonic source of nutrition. As development continued, the body of the embryo began to coil. After about 70–80 days, young N.arthritica cumingii started to emerge through a hole underneath the capsule. Biochemical results showed that the total amount of amino acids showed a decreasing trend as embryonic development progressed. The content of all nine essential amino acids decreased significantly from the egg‐swallowing stage to the post‐larva stage (p < .05). Concentrations of five of the seven nonessential amino acids also showed a decreasing trend from the egg‐swallowing stage to the post‐larva stage; the exceptions were Ala and Gly. Gly is the only amino acid that consistently increased in concentration during the development process. Most fatty acids increased after the eggs hatched, except for C20:1, C20:2, C22:5 and C22:6 (docosahexaenoic acid, DHA). The data in this study may provide a starting point for the formulation of well‐balanced early‐stage larval diets, although N.arthritica cumingii is still in the exploration stage.     

药浴暴露下阿维菌素在异育银鲫体内蓄积和消除规律

采用UPLC-MS/MS法研究了2μg·L-1三次连续水体药浴和6μg·L-1一次性水体药浴条件下阿维菌素在水体中消除、在异育银鲫(Carassius auratus gibelio)体内蓄积和消除变化规律。结果显示,两种药浴暴露方式下阿维菌素在水体中消除呈一级指数衰退消除,消除半衰期(t1/2)均为63 h,240 h时浓度下降到0.5μg·L-1以下。阿维菌素在异育银鲫血浆和肌肉中的含量均呈先升高后下降的趋势,血浆中药物浓度远高于肌肉中的含量。2μg·L-1连续三次药浴组和6μg·L-1一次药浴组血药峰浓度(Cmax)分别为34.97、66.62μg·L-1,其曲线下面积(AUC0-t)分别为9 871.2μg·L-1·h和18 119.6μg·L-1·h;两组药浴肌肉中达峰浓度分别4.42μg·kg-1和15.80μg·kg-1,其AUC0-t分别为641.9μg·kg-1·h和4 271.0μg·kg-1·h。与2μg·L-1连续三次药浴组相比,6μg·L-1一次药浴组阿维菌素在血浆和肌肉中的蓄积作用更加显著。以10μg·kg-1作为阿维菌素在异育银鲫肌肉中最大残留限量,选择95%的置信区间计算异育银鲫肌肉组织中休药期,本研究中2μg·L-1连续三次药浴组肌肉的休药期为295.4 h,6μg·L-1一次药浴组肌肉的休药期为454.5 h。     

水产养殖面源污染控制的最佳管理实践

随着水产养殖规模和产量的不断攀升,水产养殖造成的环境污染问题逐渐引起世界范围内的广泛关注。水产养殖污染是农业面源污染的重要组成部分,通过各种措施进行高效治理和保护,将极大地有利于养殖业的健康和可持续发展。美国在水产养殖面源污染控制方面走在世界前列,具有较多经验可供借鉴。文章对美国水产养殖中应用最佳管理实践（BMP）的概念、内涵和研究应用情况作了简要介绍;对BMP中在工程上和非工程上的2种管理方法进行了深入分析,特别针对工程上和非工程上的关键问题进行了阐述,并提出中国水产养殖生产中应用BMP的重要性。     

伊维菌素在水产养殖中的应用及其水生态风险

伊维菌素是一种广谱抗寄生虫渔药,在国外被广泛用于鲑鱼、海鲷养殖中的海鲺防治.国内主要用于防治淡水鱼养殖中的各种寄生虫病,其在观赏鱼养殖中的应用也日益普遍.综述了目前国内外伊维茵素在水产养殖中的使用现状,并就其水生态风险进行评估.     

Impacts of diet on hindgut microbiota and short‐chain fatty acids in grass carp (Ctenopharyngodon idellus)

Diet is known to influence intestinal microbiota in fish, but the specifics of these impacts are still poorly understood. Different protein/fibre ratio diets may result in differing structures and activities of gut microbiota. We examined the hindgut microbiome of grass carp (Ctenopharyngodon idellus) fed three different diets: fish meal (FM, high protein – low fibre), Sudan grass (SG, high fibre – low protein) and compound feed (CF, intermediate). Microbial profiles of fish fed on FM were significantly different from profiles of fish fed CF and SG (F = 18.85, p < .01). Cetobacterium, known to be positively associated with protein digestion, was the dominant microbial group in FM samples (approximately 75.7%), while Lachnospiraceae and Erysipelotrichaceae, thought to be involved in fermentation of plant polysaccharides, were dominant in CF and SG samples (46.8% and 42.9% respectively). Network analyses indicated that the abundance of Lachnospiraceae and Erysipelotrichaceae was in a significantly positive correlation (r = .895, p = .001). Short‐chain fatty acid (SCFA) levels may indicate that the digestibility of diet by microbiota in the grass carp gut decreased from FM to SG (FM>CF>SG). Overall low SCFA levels indicate that hindgut fermentation probably provides a low proportion of energy requirements in grass carp.     

中国深远海养殖发展方式研究

在渔业转型发展进程中,发展深远海养殖是突破生态环境和自然资源约束性挑战,实现新时期中国海水养殖业可持续发展的战略方向。基于联合国粮食及农业组织(FAO)关于深远海养殖发展的定义,结合中国海水养殖业发展水平和海域条件,对中国深远海养殖概念进行了界定。提出养殖品种选择、养殖系统构建、养殖海域规划是关系深远海养殖产业稳步有序发展的重要因素。在养殖品种选择方面,应重点考虑经济潜力、适应水温和养殖技术;在养殖系统构建上,分析比较了不同养殖系统应用于深远海养殖的适宜性、安全性和经济性;在养殖海域规划方面,应重点考虑养殖排放、环境承载力和海域条件。     

网箱与微流水养殖的齐口裂腹鱼肌肉营养成分的比较与分析

本研究比较和分析网箱与微流水两种养殖模式下体质量(76.5±17.8)g和(67.2±8.1)g的齐口裂腹鱼Schizothorax prenanti肌肉常规营养成分。结果显示:两组齐口裂腹鱼肌肉中一般营养成分含量不存在显著性差异,均含有18种氨基酸;除色氨酸(Trp)和组氨酸(His)外,网箱组齐口裂腹鱼肌肉中其余氨基酸、氨基酸总量、必需氨基酸总量和鲜味氨基酸总量均显著低于微流水组。氨基酸评分(AAS)和化学评分(CS)结果显示:两组齐口裂腹鱼肌肉中必需氨基酸构成合理,色氨酸均为第一限制性氨基酸,赖氨酸在必需氨基酸中评分最高。两组齐口裂腹鱼肌肉中均含有21种脂肪酸,网箱组饱和脂肪酸(SFA)总量和单不饱和脂肪酸(MUFA)含量显著低于微流水组,而多不饱和脂肪酸(PUFA)含量显著高于微流水组,且n-3/n-6比值要高于网箱组。综上所述,微流水养殖的齐口裂腹鱼营养价值更高。     

沙颍河周口段水质生物学检测及评价

对沙颍河周口段水质进行检测,包括微生物学检测、叶绿素a测定等,结合理化检测对其水质做出初步评价.结果表明大闸上游段水质为β-中污带,贫营养型;胜利桥段水质为α-中污带,中营养型;地区医院段水质为多污带,属富营养型.     

鲂鱼受精早期精子入卵的扫描电子显微镜观察

用光学显微镜观察精子进入活卵是相当困难的。作者用扫描电子显微镜初步揭示了鲂鱼受精早期精子入卵的程序，讨论了精子入卵的路径、时间和时限，并初步分析了单精入卵的机制。