铜绿微囊藻对克氏原螯虾幼虾存活及成虾几种酶类的影响

为研究铜绿微囊藻对克氏原螯虾的影响,将克氏原螯虾幼虾及成虾暴露在不同浓度的铜绿微囊藻溶液中,研究了铜绿微囊藻对幼虾存活率、外部形态及肝胰腺超微结构的变化和成虾总血细胞密度(THCs)、血清中血蓝蛋白含量、总超氧化物歧化酶(T-SOD)、过氧化物酶(POD)、酚氧化物酶(PO)以及鳃丝Na⁺/K⁺-ATP酶活性的影响。结果表明,(1) 高浓度的铜绿微囊藻能显著降低幼虾的存活率。(2) 显微观察表明,1.0×10⁷/mL及以上浓度的铜绿微囊藻液中培养7 d后,幼虾肝胰腺呈现暗红色,并伴有一定的肿大现象,透射电镜显示其肝胰腺细胞受到损伤。(3) 高浓度的铜绿微囊藻能造成应激反应,THCs在暴露1 d后显著升高并稳定在较高水平;血蓝蛋白含量变化不明显,只在5 d时显著低于对照组(P<0.05),PO活性都表现出先显著性增强(P<0.01),回落后又有所增加的波动趋势;血清中的T-SOD活力在1 d后受到抑制,5 d时被激活至较高水平;POD活性都表现出先显著性增强(P<0.01),回落后又有所增加的波动趋势;鳃丝中Na⁺/K⁺-ATP酶活性在暴露1 d后显著降低(P<0.01)后回升,并最终维持在较高水平。研究结果表明,高浓度的铜绿微囊藻能造成克氏原螯虾幼虾存活率显著降低并影响其肝胰腺超微结构;而克氏原螯虾成虾对铜绿微囊藻有相对较强的耐受力,血淋巴的酶学变化表明,暴露在铜绿微囊藻水体的成虾经历过应激反应并有逐步适应的过程。     

复方中草药制剂对克氏原螯虾抗白斑综合征感染研究

为评价饲料中添加大黄、黄芩、茵陈、地锦草、白术、板蓝根制成的复方中草药制剂对克氏原螯虾非特异免疫、抗氧化能力和抗白斑综合征病毒感染的效果,在空白饲料中分别添加0.5%、1.0%、1.5%和2.0%的复方中草药连续投喂克氏原螯虾14 d,分析克氏原螯虾血清非特异免疫酶活、肝胰腺抗氧化能力及其对白斑综合征病毒抗感染能力。试验结果显示,以摄食空白饲料的克氏原螯虾为对照,摄食复方中草药制剂的克氏原螯虾血清溶菌酶、酚氧化酶、酸性磷酸酶和碱性磷酸酶的活性分别增加了4.07%～16.20%(P<0.05)、12.96%～31.94%(P<0.05)、32.36%～39.87%(P<0.05)、36.50%～71.94%(P<0.05),肝胰腺总超氧化物歧化酶、过氧化氢酶和总抗氧化能力分别提升了4.39%～25.76%(P<0.05)、32.85%～93.43%(P<0.05)、21.52%～55.10%(P<0.05),肝胰腺丙二醛含量降低了26.22%～45.05%(P<0.05)。此外,复方中草药制剂处理的克氏原螯虾人工感染白斑综合征病毒5 d的存...     

发酵饲料对克氏原螯虾生长性能、肌肉品质、抗氧化能力和肠道微生物群落的影响

为探究克氏原螯虾配合饲料经发酵处理后的饲喂效果，分别用未发酵和发酵饲料在室内循环水系统中饲养体重为(4.91±0.18) g的克氏原螯虾幼虾8周，采样分析发酵饲料对克氏原螯虾生长、肌肉品质、消化力、抗氧化能力及肠道菌群结构的影响。结果显示，(1)发酵饲料水中溶失率显著低于未发酵饲料；(2)发酵饲料显著提高克氏原螯虾增重率和特定生长率，降低饲料系数，但对存活率、肝体比、含肉率和体成分无显著影响；(3)发酵饲料显著提高克氏原螯虾肌肉硬度、弹性、咀嚼性和胶黏性，降低了黏附性；(4)发酵饲料显著提高克氏原螯虾肝胰腺及肠道中胰蛋白酶和脂肪酶活性，血清和肝胰腺中超氧化物歧化酶、酸性磷酸酶和碱性磷酸酶活性，以及肝胰腺总抗氧化能力；(5)发酵饲料显著提高了肠道绒毛长度和宽度；(6)发酵饲料改善了克氏原螯虾肠道微生物结构，显著升高了厚壁菌门和放线菌门相对丰度，同时提高了肠道菌群多样性。研究表明，饲料经发酵处理后可以有效提高克氏原螯虾生长性能、肌肉品质、消化力和抗氧化能力，改善了肠道组织结构，改变了肠道微生物结构，为克氏原螯虾新型环保饲料的生产提供理论依据。     

维生素C对克氏原螯虾肝胰腺非特异性免疫的影响

为探究维生素C作为饲料添加剂短期投喂克氏原螯虾(Procambarus clarkii)对其肝胰腺非特异性免疫的影响,并寻找出最适的添加量,将规格相同(27 g±3 g)、健康无伤的克氏原螯虾暂养7 d后分5组,对照组投喂基础饲料,4个试验组投喂的饲料为在基础饲料中添加维生素C(添加量分别:0.1、0.2、0.4、0.8 g/kg)。投喂5 d后,取试验虾肝胰腺进行免疫相关酶活指标的测定,结果显示:添加0.2 g/kg的维生素C可以显著提升克氏原螯虾肝胰腺中SOD、CAT、T-AOC等抗氧化酶的活性,对于免疫酶ACP、AKP的活力依然有显著提升作用。并且对于肝胰腺中MDA的含量有降低作用(P<0.05)。0.4 g/kg添加组,能够显著提升肝胰腺中CAT活力,并且显著降低MDA含量(P<0.05)。由此可以得出在饲料中添加0.2~0.4 g/kg维生素C可以在一定程度上提升克氏原螯虾肝胰腺的非特异性免疫。     

饲料蛋白质水平和加工工艺对克氏原螯虾生长性能、消化力和抗氧化性能的影响

为研究不同蛋白质水平和加工工艺饲料对克氏原螯虾(Procambarus clarkii)生长性能、消化力和抗氧化能力的影响，本研究采用4个蛋白质水平(28%、30%、32%和36%)和2种加工工艺即膨化饲料(EF)和硬颗粒饲料(PF)的4×2双因素实验设计，进行为期13周的养殖实验。结果显示，蛋白质水平和加工工艺对克氏原螯虾增重率和肝体比有显著的交互作用(P<0.05)。主效应结果显示，28%蛋白质可显著提高增重率和特定生长率，EF组的末重和增重率显著高于PF组(P<0.05)。蛋白质水平和加工工艺对肝胰脏的胰蛋白酶和淀粉酶活性有交互作用(P<0.05)。主效应结果显示，肝胰脏的胰蛋白酶、淀粉酶和肠道胰蛋白酶、淀粉酶均在28%蛋白质水平时最高，EF组肝胰脏胰蛋白酶、淀粉酶和肠道胰蛋白酶活力高于PF组(P<0.05)。蛋白质水平和加工工艺对肝胰脏的丙二醛和碱性磷酸酶活性有显著的交互作用(P<0.05)。主效应结果显示，肝胰脏碱性磷酸酶活性以及血清的碱性磷酸酶和酸性磷酸酶均在28%蛋白质水平时最低。PF组肝胰脏丙二醛含量显著低于EF组(P<0.05)，碱性磷酸酶活性显著低于EF组(P<0.05)。4种模型(Logistic、Gompertz、Von Bertalanffy和Brody)均能很好地模拟克氏原螯虾体重和体长的生长曲线，拟合度均大于0.97，其中，以Logistic模型拟合克氏原螯虾体重和体长最优，且幂函数可以反映体重和体长之间的关系。综上所述，28%蛋白质水平和膨化加工工艺使克氏原螯虾具有最优的生长性能和消化力，28%蛋白质水平的硬颗粒饲料可提高克氏原螯虾的抗氧化能力。     

克氏原螯虾病原菌感染发病标志性免疫及生理生化指标的筛选

为筛选克氏原螯虾(Procambarus clarkia)因受病原菌感染导致发病的标志性生理生化指标, 以嗜水气单胞菌 (Aeromonas hydrophila)为攻毒菌株, 采用半致死剂量注射感染克氏原螯虾, 分析了感染初期(12 h)、发病期(24~72 h)和感染后恢复期(90 h)血淋巴中的非特异免疫、糖类代谢、脂类代谢、蛋白质代谢及常规生理生化指标共 23 项, 结果显示, 在发病期, 8 项非特异免疫指标中, 感染组过氧化氢酶(CAT)活力和总抗氧化能力(T-AOC)在发病状态下提高显著(P＜0.01), 均值分别是空白对照组的 3.29 倍和 2.56 倍; 感染组发病期蛋白代谢指标白蛋白(ALB)和尿素(UREA) 浓度极显著提高(P＜0.01), 其浓度均值比空白对照组分别提高了 1.75 与 5.58 倍; 感染组发病期消化酶指标中淀粉酶(AMY)活力在发病过程中活性显著下降(P＜0.01), 比空白对照组下降了 74.18%; 血清中肌酸激酶(CK)、谷丙转氨酶(ALT)、谷草转氨酶(AST)和谷胱甘肽过氧化物酶(GSH-Px) 4 种酶活力在发病期显著提高(P＜0.01), 与空白对照组比分别提高了 16.72、219.21、74.43、2.66 倍。在所检测指标中, 葡萄糖(GLU)、甘油三酯(TG)、总蛋白(TP)和脂肪酶(LPS) 4 项指标在克氏原螯虾发病过程中均变化不显著(P＞0.05)。结果表明, 克氏原螯虾血清中 CAT、T-AOC、 ALB、UREA、AMY、CK、ALT、AST 及 GSH-Px 9 项指标变化对细菌感染发病极敏感, 可作为判断其受细菌病感染发病的标志性指标。本研究结果可为克氏原螯虾患病风险评估和疾病预警提供新的技术依据。     

维生素C对克氏原螯虾生长及非特异性免疫机能的影响

为探讨维生素C对克氏原螯虾生长及非特异性免疫机能的影响,以初始体质量(3.19±0.06)g的克氏原螯虾为试验对象,分别投喂维生素C添加量为0(对照),30、60、120、240和480 mg/kg的等能等氮饲料,进行为期60 d的养殖试验。结果表明,饲料维生素C添加水平对克氏原螯虾的存活率(SR)、肝胰腺指数(HSI)、肥满度(CF)及饲料系数(FCR)没有显著影响(P0.05),增重率(WGR)和特定生长率(SGR)随饲料维生素C含量增加先上升后下降,其中120 mg/kg组增重率和特定生长率显著高于其他各组(P0.05);克氏原螯虾血浆溶菌酶(LZM)活性以120 mg/kg组最高,且显著高于其他各组(P0.05),酸性磷酸酶(ACP)和碱性磷酸酶(AKP)活性变化趋势一致,均以120 mg/kg组最高,显著高于除480 mg/kg组外的其他各组(P0.05);克氏原螯虾肝胰腺超氧化物歧化酶(SOD)活性不受维生素C添加水平影响(P0.05),肝胰腺过氧化氢酶(CAT)活性随饲料中维生素C含量的增加先升高后降低,120 mg/kg组显著高于其他各组(P0.05),120 mg/kg组肝胰腺丙二醛(MDA)含量显著低于其他组(P0.05)。可见,饲料中适量的维生素C(120 mg/kg)可促进克氏原螯虾生长,提高机体免疫和抗氧化能力。     

几种诱食剂对克氏原螯虾生长、血清生化指标及消化酶活性的影响

为研究饲料中添加诱食剂对克氏原螯虾生长、血液生化指标、肌肉常规营养成分及消化酶活性的影响,以初始体质量为(4.29±0.03)g的克氏原螯虾(Procambarus clarkii)为试验对象,选用克氏原螯虾231只,随机分为7个处理组,每个处理设3个重复,每组重复11只。采用单因素试验设计,在基础饲料中分别添加1%甜菜碱、TMAO、DMPT、复合氨基酸、大蒜素和复合诱食剂(40%甜菜碱+20%TMAO+20%DMPT+20%大蒜素),试验结束后测定克氏原螯虾生长性能、血清生化指标、肌肉常规营养成分和消化酶活性。结果显示,与对照组相比,在饲料中添加甜菜碱、TMAO、复合氨基酸、大蒜素、复合诱食剂均能显著提高克氏原螯虾的增重率,降低饲料系数(P0.05),复合诱食剂还可以显著提高其摄食率(P0.05);而对存活率没有显著影响(P0.05)。DMPT、复合氨基酸和复合诱食剂组均能显著降低血清谷丙转氨酶的水平;复合氨基酸组还能显著降低胆固醇的水平(P0.05)。添加甜菜碱、TMAO、DMPT、大蒜素和复合诱食剂组肌肉粗脂肪含量显著高于对照组(P0.05)。此外,在日粮中添加诱食剂能提高虾肠道消化酶活性(P0.05)。各组间血清谷草转氨酶、葡萄糖、总蛋白和白蛋白水平、肌肉水分和灰分含量差异均不显著(P0.05)。综上所述,饲料中添加诱食剂能显著提高克氏原螯虾的摄食、生长以及消化酶的活性。其中,复合诱食剂(40%甜菜碱+20%TMAO+20%DMPT+20%大蒜素)对促进克氏原螯虾生长效果最显著。     

利用生物絮团技术对克氏原螯虾的养殖效果初探

为探究将生物絮团技术应用到克氏原螯虾养殖的可能性，本实验利用生物絮团技术和普通饲料投喂2种方式短期养殖体质量为(9.70±0.32) g的克氏原螯虾30 d。比较养殖期间2实验组的水化学指标以及实验结束时2实验组幼虾的生长情况，肌肉及肝胰腺营养成分组成，胃、肠和肝胰腺组织的消化酶活性，肝胰腺和肌肉组织的抗氧化能力。结果显示，①在养殖期间，絮团组水体总氮(TN)、亚硝态氮(NO₂^--N)、硝态氮(NO₃^--N)的质量浓度均维持在较低的水平。②本实验条件下2实验组虾的终末体质量、增重率(WG)、特定生长率(SGR)、存活率(SR)均无显著差异。③絮团的粗蛋白含量可以达到36.8%，能够满足克氏原螯虾对于蛋白的需求。但絮团的粗脂肪含量较低，这也影响了絮团组幼虾肌肉组织的粗脂肪沉积量。④絮团组幼虾肝胰腺中α-淀粉酶(α-AL)、脂肪酶(LPS)、纤维素酶(CL)活性均显著高于饲料组幼虾，而饲料组幼虾在胃、肠组织中的α-AL活性较高，2实验组幼虾的胃蛋白酶活性无明显差异。⑤絮团组幼虾的抗氧化能力与饲料组幼虾相比，肝胰腺中超氧化物歧化酶(SOD)活性较高，丙二醛(MDA)含量较低，但总抗氧化能力(T-AOC)、过氧化氢酶(CAT)、谷胱甘肽还原酶(GR)以及溶菌酶(LZM)无明显差异。研究表明，生物絮团技术在克氏原螯虾的养殖中具有积极作用，可以达到与饲料投喂相同甚至更好的养殖效果。     

饲料中添加核苷酸对凡纳滨对虾幼虾生长、组织生化组成及非特异性免疫功能的影响

选用960尾初始体重为(0.43?0.01) g 的凡纳滨对虾,随机分为8组,分别投喂基础饲料和7种添加核苷酸混合物(mix-NT)的试验饲料,5种核苷酸(5′-腺苷酸∶5′-胞苷酸∶5′-尿苷酸二钠∶5′-肌苷酸二钠∶5′-鸟苷酸二钠)按照质量比为1∶1∶1∶1∶1(W/W)混合,添加量分别为0.1、0.2、0.4、0.6、0.8、1.0和1.2 g/kg 饲料,试验周期为5周。结果显示,当mixNT添加量为0.4 g/kg饲料时,凡纳滨对虾的增重率(WGR)、特定生长率(SGR)和摄食量(FI)显著高于对照组(P<0.05),饲料系数(FCR)比对照组降低5.5%(P>0.05)。0.6和1.0 g/kg mix-NT添加组的蛋白质沉积率(PDR)显著高于对照组(P<0.05)。试验组对虾存活率(SR)和肝胰指数(HSI)均不同程度的高于对照组,但差异不显著(P>0.05)。饲料中添加mix-NT对全虾粗脂肪、灰分含量的影响显著(P<0.05),各mix-NT添加组的全虾干物质和粗蛋白含量均高于对照组,但差异未达到显著水平(P>0.05)。肝胰腺RNA含量和总蛋白(TP)含量均随饲料中mix-NT添加量的增加而升高,其中0.2~1.0 g/kg组的肝胰腺RNA含量显著高于对照组(P<0.05),TP含量差异未达到显著水平(P>0.05);各mixNT添加组的肠道TP含量均显著高于对照组(P<0.05),0.4和0.6 g/kg组的肠道RNA量极显著高于对照组(P<0.01)。外源mix-NT显著降低血清尿酸(UA)含量(P<0.05),但对TP、谷丙转氨酶(GPT)、高密度脂蛋白(HDL)含量无显著影响(P>0.05)。当mix-NT添加量为1.2 g/kg 饲料时,血清中谷草转氨酶(GOt)活性显著性升高(P<0.05)。鳃和肌肉酚氧化酶(PO)活性均在0.4 g/kg组达到最大,其中0.1～0.6 g/kg 组的鳃PO活性显著高于对照组(P<0.05),而各组肌肉PO活性无显著差异(P>0.05)。凡纳滨对虾肝胰腺和血清中溶菌酶(LZM)活性随饲料中mix-NT添加量的增加而显著升高(P<0.05)。结果表明,饲料中添加一定量的5种核苷酸混合物能显著提高凡纳滨对虾幼虾的增重率、特定生长率、摄食量、蛋白质沉积率、全虾粗脂肪和灰分含量,一定程度提高全虾粗蛋白和肝胰腺总蛋白含量,显著增加肝胰腺RNA、肠道总蛋白和RNA含量,提高对虾的非特异性免疫功能。     

Anguilla huangi Teng, Lin, and Tzeng, 2009, is a junior synonym of Anguilla luzonensis Watanabe, Aoyama, and Tsukamoto, 2009

Anguilla luzonensis and A. huangi were each described in 2009 using eels obtained from northern Luzon Island. We examined the taxonomic status of these two groups of eels using morphological and molecular genetic characters. There were no significant differences in two vertebrae counts between eels of A. luzonensis and A. huangi. Mitochondrial 16S ribosomal RNA and cytochrome b genes sequences were obtained and compared among 28 specimens of A. luzonensis, the holotypes of A. luzonensis and A. huangi, and one specimen of the other 15 anguillid species. The specimens of A. luzonensis exhibited almost identical sequences, including the holotype, with only a few site differences, and the genetic difference between the holotypes of A. luzonensis and A. huangi was within the range of differences of specimens of A. luzonensis. The other anguillid species were genetically very different from A. luzonensis and A. huangi, although A. interioris is a closely related species. It is clear that A. luzonensis and A. huangi are the same species, and according to the principle of priority in zoological nomenclature, A. luzonensis Watanabe, Aoyama, and Tsukamoto, 2009 is the valid species name, and A. huangi Teng, Lin, and Tzeng, 2009 is a junior synonym of A. luzonensis.     

驼背鲈(Chromileptes altivelis)的胚胎发育及仔、稚、幼鱼形态观察

对驼背鲈(Chromileptes altivelis)的胚胎发育及仔、稚、幼鱼的形态特征进行了详细的观察与研究,描述了从受精卵到仔、稚、幼鱼各发育期的时间和形态特征变化。结果表明,在水温25-26℃、盐度30的海水中,受精卵历时27 h 25 min完成整个胚胎发育过程,经历从卵裂、囊胚、原肠、神经胚到肌节形成、各器官的逐渐形成、变化、完善等一系列的胚胎发育和变化过程;根据其卵黄囊消长情况、鳞片的覆盖状态、体色发生的不同变化以及第二背鳍和腹鳍的消长,将胚后发育分为仔、稚、幼鱼3个阶段。在水温22-26℃、盐度29-31、DO≥5 mg/L的条件下,2-3 d仔鱼卵黄囊消失,开口摄食;生长发育至31 d,仔鱼已变态进入稚鱼期;培育至57 d,稚鱼完成变态,成为幼鱼。第二背鳍棘和腹鳍棘的生长与收缩等石斑鱼类早期发育的共性生长特征及其体表特性体色变化特征为驼背鲈胚后发育过程中最明显的特征。     

Marine and coastal protected and conserved areas strategy in Brazil: Context,lessons, challenges,finance, participation,new management models,and first results

1. In the last two decades, Brazil has advanced significantly with the expansion and improvement of its national system of protected areas. Until recently most of the expansion was concentrated in the Amazon region (with useful lessons). It also had an uneven ecological representation of coastal and marine ecosystems, concentrated in coastal waters. Despite significant advances, the levels of funding, staff and stakeholders' engagement remain relatively low for such a vast system.
2. Within the past few years, key elements of a new strategy for protection of coastal and marine areas have started to emerge, combined with some participatory processes and a focus on expansion of the total area protected (from <1.5% protection of the country's marine area). These included: a renewed focus on priority areas for conservation; attention to national and international commitments and targets; clarity about the need for partnerships and funding; better engagement of Brazilian society and stakeholders; new, and more collaborative, models of protected areas management and conservation; and openness in the relationships with wider society.
3. Significant results of this effort have started to appear: new large mosaics of oceanic protected areas were created; Amazon mangroves were recognized by the Ramsar Convention; new mangrove protected areas were created, besides other ones proposed; project proposals are under development with partners for better funding and sharing of responsibility; and there is a better engagement with stakeholders. The building of the Brazilian Blue Initiative is underway.
4. The implementation of the proposed 15‐year marine strategy is at its onset: partnerships need to be strengthened and substantial funding is required. It will only be possible to manage the larger system of protected areas if there are more collaborative and innovative models for protected areas and conservation management. These should include partnerships with civil society, local and traditional communities and the private sector, as well as greater engagement of scientists and research institutions, stronger and more qualified tourism, volunteer work, etc. Further innovative funding mechanisms will also be needed along the way.

     

Brazilian wetlands: their definition,delineation, and classification for research,sustainable management,and protection

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Mercury and methyl mercury concentration in sediment,benthic, Barbus Grypus and pelagic,Barbus esocinus fish species,from Musa estuary,Iran

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