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11.
为了解海南尖鳍鲤(Cyprinus acutidorsalis)线粒体基因组结构特征及其与鲤科(Cyprinidae)鱼类的进化关系,本文通过二代测序获得海南万泉河口尖鳍鲤线粒体基因组全序列,并对结构特征进行分析,结果显示具有典型的环状闭环双链分子,全长16581bp,碱基组成为A(31.96%)、G(15.69%)、C(27.53%)和T(24.82%),包含13个蛋白质编码基因(protein-codinggenes,PCGs)、2个r RNA基因、22个tRNA基因和1个可变控制区D环。对碱基含量分析发现尖鳍鲤的碱基组成中具有较高AT含量的偏向性,13个PCGs中有不少的偏好性密码子,如CGA(RSCU>3.506)、CCA(RSCU>2.208)等。除tRNAGln、tRNAAla、tRNAAsn、tRNACys、tRNALeu(CUN)、tRNATyr、tRNASer(UCN)、tRNAPro  相似文献   
12.
镉离子对鲫鱼肾细胞超微结构的影响   总被引:2,自引:0,他引:2  
应用透射电镜的方法,研究了镉的三种浓度对鲫鱼肾细胞超微结构的影响。结果表明:镉离子染毒4天后,肾细胞超微结构即出现变化,且随着处理浓度的升高,变化渐趋明显,主要表现在细胞核和线粒体。细胞核核膜肿胀、弥散、最后解体。线粒体双层膜解体,形成空白区,嵴断裂、膨大和扭曲。此外,内质网膨胀、空泡化、扭曲打转,溶酶体数量和类型随镉处理浓度的升高而增多。  相似文献   
13.
黄河鲤鱼和鲤鱼同工酶的研究   总被引:1,自引:0,他引:1  
本文采用聚丙烯酰胺凝胶垂直平板电泳,分析了黄河鲤鱼Cyprinus carpiohaematopterus和鲤鱼Cyprinus carpio的脑、肝、心、肾、肌、眼等六种组织器官的乳酸脱氢酶(LDH)同工酶和脂酶(EST)同工酶。结果表明:在不同组织中两种同工谱带各不相同,存在着明显的组织特异性。黄河鲤鱼和鲤鱼的乳酸脱氢酶谱带相似,但存在一定的差异性;除在眼、心、肾三种组织中黄河鲤鱼比鲤鱼多一条  相似文献   
14.
The effect of hexavalent chromium on the carp,Cyprinus carpio was assessed using static bioassay. The 96h LC50 was found to be 93.6mg · l–1. In carp exposed to sublethal concentrations of chromium (15 and 25 mg · l–1), significant depletion of liver and muscle glycogen and decreasing leucocyte counts were recorded during prolonged exposure and with increasing concentration of chromium. The other blood parameters examined (haemoglobin, erythrocyte count, hematocrit, serum protein, serum glucose) increased similarly during exposure to two chromium concentrations.  相似文献   
15.
天然植物提取物对鲤鱼生长性能及血液学指标的影响   总被引:2,自引:0,他引:2  
于建鲤(Cyprinuscarpio var.jian)饲料中添加质量分数0.10%、0.15%和0.20%天然植物提取物(类黄酮、多糖),研究天然植物提取物对建鲤生产性能及血液学指标的影响,确定适宜的添加量。结果表明,综合比较成活率、饵料系数、单位产量等指标后,提取物添加量以0.15%为最佳。0.15%添加量组与对照组比较,成活率提高4.7%,饲料系数提高10%,单位产量提高18.8%,血液指标中红细胞增加44.5%、白细胞增加45%、中性白细胞增加15.22%、血红素增加10.6%。表明天然植物提取物(类黄酮、多糖)具有多种生物学效应。  相似文献   
16.
在网箱养殖 45 天后, 采用比较分析黑龙江野鲤与建鲤正反交与自交子代消化酶活力的方法, 研究由杂交引起的遗传背景改变对消化酶活力及其分布的影响。 结果表明, 两杂交群体肝胰腺蛋白酶活力显著高于建鲤自交子代, 后肠则显著低于后者, 后肠脂肪酶活力显著高于黑龙江野鲤自交子代; 黑龙江野鲤×建鲤♀子代各消化器官淀粉酶活力均显著高于两自交群体。两杂交群体除前、中肠淀粉酶活力差异显著度与建鲤自交子代不同外, 3 种消化酶活力分布及不同器官间的差异程度和两自交群体均相同; 四个群体脂肪酶和淀粉酶活力在前、中肠及肝胰腺均表现出互补现象, 后肠均有较高活力不互补。  相似文献   
17.
Introduced common carp (Cyprinus carpio) are a recognised threat to New Zealand’s freshwater ecosystems. In 2011, an invasive fish removal programme was undertaken in 16.8 ha Lake Ohinewai, a Waikato riverine lake. Active fish removal using netting and boat electrofishing was supported by installation of a one-way exclusion barrier on the outflow to Lake Ohinewai. The barrier was designed to allow fish passage downstream out of the lake, while preventing adult carp from moving upstream. The estimated carp population was reduced from 8,548 fish (5,863–12,937, 95% confidence limits) in 2011–454 fish (251–889, 95% CL) in 2014. However, by 2016 the carp population had recovered to 2,063 fish (1,070–4,328, 95% CL) with increased abundance in invasive brown bullhead catfish (Ameiurus nebulosus) also observed. This research demonstrates that carp populations can be reduced to low abundances in the short to medium term, but continued removal will be required for on-going control.  相似文献   
18.
三角鲤的胚后发育过程可分为早期仔鱼、晚期仔鱼和稚鱼3个阶段共11个时期。与其他鲤科鱼类比较,三角鲤胚后发育具卵黄囊吸收迅速、鳔迅速发育成形(巡游模式迅速建立)及鳞片的较早出现、长齐和完成胚后发育时间较短等特点;在水温为25.0±0.7℃的条件下,全长5.2±0.2 mm的初孵仔鱼经过24~26 d的发育,全长达20.6±0.3 mm即完成胚后发育;仔鱼、稚鱼的全长随日龄呈线性生长,相关方程式为L=5.8591+0.6254 A(r=0.999 2,P<0.01),每日增长约为0.63 mm。根据三角鲤胚后发育特点讨论了鱼苗生产应注意的问题。  相似文献   
19.
采用周期性饥饿再投喂的方法,研究周期性饥饿再投喂对建鲤(1.5±0.2g)的生长、体组成、消化酶的影响。试验分为10个组,共进行60d。结果表明,在相同的饥饿天数下,延长再投喂天数可以使建鲤的增重率逐渐增加,而且S1F4、S2F8、S4F16组的增重率与对照组无显著性差异(P〉0.05),9个周期性饥饿再投喂组在摄食期...  相似文献   
20.
Community engagement is understood to be one of the keys to successful environmental programs—‘the social pillar’ of management. In this paper we examine community engagement where volunteers participate by killing invasive animals. Most research to date focuses on the biological or management implications of volunteer efforts for the invasive species, with little attention to the people involved or the social acceptability of killing animals in this context. Here, we report on a survey and participant observations of community fishing events in south-eastern Australia, where volunteers fish for and kill carp (Cyprinus carpio). We examine who takes part in these events, their motivations for being involved and the implications for ongoing community engagement. Survey respondents were predominantly well-educated Australian-born men, motivated to fish by a desire to spend time in nature. However, we also noted a strong response from overseas-born men with different motivations. Our survey elicited complex responses regarding killing, illustrating contradictory, sometimes conflicted experiences, which jar with personal motivations. The implications are that questions of ethics must extend to the human volunteers, and that more direct communication of program outcomes and the proposed benefits for volunteers be more rigorously assessed. We argue that invasive species management must contend with the experiences of volunteers, otherwise meaningful dialogue and program objectives risk being undermined.  相似文献   
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