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1.
不同循环投喂模式对半滑舌鳎的生长、体成分组成、代谢和能量收支的影响 总被引：2，自引：2，他引：0
研究了不同循环投喂模式对半滑舌鳎的生长、体成分组成、代谢和能量收支的影响。其中包括5个处理:C(对照组,实验过程中持续投喂);S2F4组(饥饿2 d,投喂4 d);S4F8组(饥饿4 d,投喂8 d);S8F16组(饥饿8 d,投喂16 d);S12F24组(饥饿12 d,投喂24 d),实验时间72 d。结果表明,对照组的特定生长率(SGRw和SGRe)显著高于循环投喂各组(P<0.05)。对照组和S2F4组半滑舌鳎幼鱼的末体重没有显著差异(P>0.05),并且均显著高于其它各组(P<0.05)。对照组半滑舌鳎幼鱼的消化率显著低于其它各组(P<0.05),而能量消化率与S12F24组没有显著差异(P>0.05),但显著低于其它3个处理组(P<0.05)。S4F8组半滑舌鳎幼鱼饲料转化率显著低于S12F24组(P<0.05),对照组饲料转化率低于S2F4组和S12F24组但没有显著差异(P>0.05)。对照组半滑舌鳎幼鱼的摄食率显著低于其它各组(P<0.05)。体成分组成中,蛋白含量随饥饿、投喂周期的延长而下降,S2F4组和对照组半滑舌鳎的蛋白含量没有显著差异(P>0.05)。S2F4组的耗氧率和排氨率均较低。对照组的摄食能显著高于其它各组(P<0.05),S2F4组的呼吸能占摄食能的比例显著高于对照组(P<0.05)。研究表明,半滑舌鳎幼鱼在循环投喂模式下,具有较强的补偿生长能力,S2F4组具有完全补偿生长能力;在较长的周期性饥饿条件下,半滑舌鳎幼鱼体内的蛋白质含量会受到显著影响。 相似文献
2.
硫酸软骨素在生物体应对病毒和细菌感染中起着重要作用, 为研究硫酸软骨素合酶 1 (chondroitin sulfate synthase-1, ChSy-1)在仿刺参(Apostichopus japonicus)受到灿烂弧菌(Vibrio splendidus)感染后的作用, 本研究开展了仿刺参 ChSy-1 基因(AjChSy-1)全长序列克隆和结构及系统进化分析, 并采用荧光定量 PCR 技术测定了该基因在刺参不同组织中的表达差异及灿烂弧菌感染下的表达模式。结果显示, AjChSy-1 基因 cDNA 全长为 2756 bp, 其中, 5′-UTR 长度为 194 bp, 3′-UTR 为 228 bp, ORF 为 2334 bp, 编码 777 个氨基酸。AjChSy-1 基因编码的蛋白含有糖基转移酶保守性 DXD 基序、β3-糖基转移酶基序及 β4-糖基转移酶基序等结构。刺参基因组比对发现在 chr13 染色体上存在 2 个 AjChSy-1 基因拷贝。系统进化分析表明, 刺参 AjChSy-1 编码蛋白与玉足海参(Holothuria leucospilota) 和棘冠海星(Acanthaster planci)的蛋白亲缘关系较近, 与斑马鱼(Danio rerio)、智人(Homo sapiens)等脊椎动物的蛋白亲缘关系较远。荧光定量 PCR 显示, AjChSy-1 基因具有广泛的组织表达特性, 其中, 体腔细胞中表达量最高, 体壁、性腺(雄性和雌性)和纵肌次之。在响应灿烂弧菌侵染过程中, 随灿烂弧菌侵染时间增加, 体壁中 AjChSy-1 表达量呈现先上升后下降的趋势, 在第 3、6、9 天分别为对照组的 1.79、2.06、3.12 倍, 对发病期抗病群体和易感群体中该基因的检测结果表明, 易感群体体壁该基因表达量显著低于抗病群体(P＜0.05), 表达量降低 11.4%。推测该基因可能在刺参应对灿烂弧菌中发挥免疫防御作用, 相关研究结果为解析刺参 AjChSy-1 基因功能以及抗病分子调控机制提供了参考数据。 相似文献
3.
核转录因子 NF-κB 家族在无脊椎动物抵抗病原刺激中起着重要作用。本研究通过 RACE 技术克隆了长毛明对虾(Fenneropenaeus penicillatus) NF-κB 家族基因, 分别命名为 FpRelish 和 FpDorsal。FpRelish cDNA 全长为 5373 bp, 其中 5?UTR 88 bp, 3?UTR 1667 bp, 编码区 3618 bp, 编码 1205 个氨基酸; FpDorsal cDNA 全长为 4816 bp, 其中 5?UTR 611 bp, 3?UTR 2147 bp, 编码区 2058 bp, 编码 685 个氨基酸, 两者均具有 RHD 结构域。同源性和系统进化分析表明, FpRelish 和 FpDorsal 都分别与甲壳动物首先聚为一支。qPCR 分析表明, 两基因在检测的血液、心脏、肝胰脏、鳃、肠道、性腺、肌肉、神经和胃组织中均有表达, 且均在肝胰脏中最低, 在血细胞中最高, 相差 8~ 10.7 倍。嗜水气单胞菌(Aeromonas hydrophila)刺激后, FpRelish 和 FpDorsal 基因在鳃和肝胰脏中均有先上升再下降的表达变化模式, 鳃中 FpRelish 基因 6 h 表达最高, 为对照组 2.7 倍, FpDorsal 基因 9 h 表达最高, 为对照组 2.1 倍; 肝胰脏中 FpRelish 基因在 9 h 高表达, 最高表达量在 48 h, 为对照组的 4.5 倍, FpDorsal 基因 9 h 表达最高, 为对照组 22 倍。溶藻弧菌(Vibrio aliginolyticus)刺激后, 鳃中 FpRelish 基因 24 h 表达最高, 为对照组 1.9 倍, FpDorsal 基因 24 h 表达最高, 为对照组 1.5 倍; 肝胰脏中 FpRelish 基因 3 h 达最高表达量, FpDorsal 基因 6 h 表达最高, 均为对照组的 1.5 倍。本研究表明 FpRelish 和 FpDorsal 在长毛明对虾免疫调控中发挥了重要作用。 相似文献
4.
为探讨饲料代替活饵投喂对鳜(Siniperca chuatsi)胃饥饿素(ghrelin)的调控作用, 本研究通过转录组测序和基因组测序数据匹配, 首次获得了鳜(Siniperca chuatsi)胃饥饿素前体基因 DNA 序列, 对其胃中分泌细胞进行定位。 诱食试验模拟鳜进食前看到食物但不能摄食, 进食试验模拟鳜正常摄食。研究检测了诱食、进食后胃饥饿素基因和蛋白表达水平变化。结果表明, 鳜胃饥饿素前体由信号肽、成熟肽(胃饥饿素)和 C-端肽 3 部分构成;前体基因含有 4 个外显子和 3 个内含子, 属于Ⅱ型基因型; 编码 107 个氨基酸, 成熟肽胃饥饿素由 20 个氨基酸构成, 活性中心为 GSSF。免疫组化显示胃饥饿素阳性细胞位于胃腺中。诱食试验中, 活饵组胃饥饿素 mRNA 和蛋白表达水平均显著升高; 而饲料组胃饥饿素基因 mRNA 和蛋白表达水平未发生显著变化, 且显著低于活饵组(P＜0.05)。进食实验中, 活饵组进食后 0 h, 胃饥饿素 mRNA 和蛋白表达水平显著上升(P＜0.05), 进食后 2 h 下降至摄食前水平 (P＜0.05), 后续无显著变化(P＞0.05); 饲料组进食后 0 h 胃饥饿素 mRNA 表达水平未出现显著变化(P＞0.05), 蛋白水平呈波动变化, 进食后 2 h 及后续胃排空时间内皆无显著变化(P＞0.05)。综上, 鳜胃饥饿素细胞位于胃腺位置, 参与调节摄食活动, 进食前上升, 进食后下降, 而饲料投喂下 ghrelin 对摄食调节作用明显减弱, 研究结果可为鳜饲料养殖提供科学参考。 相似文献
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《福建水产》2020,(2)
为了分析真蛸(Octopus vulgaris)长期摄食鱼类后拒食的原因,本研究进行了蓝圆鲹(Decapterus maruadsi)和锐齿蟳(Charybdis acuta)喂养真蛸试验,观察了蓝圆鲹喂养的真蛸停止摄食的时间,测定了试验组与对照组(野生真蛸)真蛸消化腺的蛋白质、氨基酸及脂肪酸组成。结果显示:蓝圆鲹组真蛸消化腺中苏氨酸、异亮氨酸、苯丙氨酸、天门冬氨酸、丝氨酸、酪氨酸、组氨酸和脯氨酸极显著低于对照组,缬草氨酸、亮氨酸、甘氨酸、丙氨酸、胱氨酸、精氨酸和非必需氨基酸总量显著低于对照组;锐齿蟳组真蛸消化腺中缬草氨酸、异亮氨酸、亮氨酸、苯丙氨酸、赖氨酸、甘氨酸和丙氨酸显著低于对照组;两试验组必需氨基酸总量均显著低于对照组;蓝圆鲹组真蛸消化腺中酪氨酸显著低于锐齿蟳组。蓝圆鲹组真蛸消化腺中C14∶0、C18∶3n3c和C22∶6n3c极显著高于对照组,C18∶0、C20∶0、C22∶0、C18∶1n9c和C20∶4n6c极显著低于对照组,单不饱和脂肪酸总量显著低于对照组,C14∶0、C16∶0和饱和脂肪酸总量显著高于锐齿蟳组;锐齿蟳组真蛸消化腺中C18∶0极显著低于对照组,C22∶0、C18∶1n9c显著低于对照组,C18∶3n3c、C20∶3n6c极显著高于对照组,C20∶5n3c和C22∶6n3c显著高于对照组;蓝圆鲹组真蛸消化腺中C14∶0、C16∶0和饱和脂肪酸总量显著高于锐齿蟳组。以上结果表明造成真蛸摄食鱼类过久最后拒食的原因不是饲料中氨基酸组成而是饱和脂肪酸的含量。试验结果将为真蛸配合饲料研究提供一些基础数据。 相似文献
6.
真核翻译起始因子 4E 结合蛋白 1 (4E-BP1)是 mTOR 信号通路下游的翻译抑制因子, 调节翻译的起始和蛋白质的合成。为探究中华绒螯蟹(Eriocheir sinensis) 4E-BP1 基因特征、时空表达模式及其在蜕壳过程中的潜在作用, 本研究利用 RACE 技术克隆获得中华绒螯蟹 Es4E-BP1 全长 cDNA 序列, 利用 qPCR 技术探究其时空表达, 利用 dsRNA 干扰探究其在中华绒螯蟹蜕壳中的作用。测序结果显示, Es4E-BP1 cDNA 全长 1678 bp, 包括 134 bp 的 5? 非编码区、1193 bp 的 3?非编码区和 351 bp 的开放阅读框。氨基酸序列分析发现, Es4E-BP1 含有 1 个 eIF4E 超级家族的典型保守域, 且包含 1 个超二级结构 TOS 基序和 1 个 YXXXXLΦ 基序。多序列比对和系统进化树分析显示, Es4E-BP1 与蓝蟹(Callinectes sapidus)、三疣梭子蟹(Portunus trituberculatus)聚为一支并且具有很高的同源性 (95.69%和 93.16%)。qPCR 结果显示, Es4E-BP1 在成蟹各个组织均有表达, 其中 Y 器官表达量最高, 其次为肌肉, 鳃丝中表达量最低。一个完整蜕壳周期内, 幼蟹不同组织表达模式不同, 但均在蜕壳后期 A-B 期表达量最高, 蜕壳前期表达量较低。注射 dsEs4E-BP1 后, 中华绒螯蟹存活率远低于对照组 CG 组; 蜕壳间隔显著高于 CG 组。研究结果表明, Es4E-BP1 在中华绒螯蟹各组织中广泛表达, 在调控蜕壳生长中具有重要作用, 为进一步研究甲壳动物 4E-BP1 基因提供了重要参考。 相似文献
7.
为探究胆汁酸对高脂饲料饲喂下大口黑鲈(Micropterus salmoides)生长生理、脂代谢和胆汁酸代谢的影响, 配制基础饲料(脂肪含量 10.6%, 对照组 C)、高脂饲料(脂肪含量 17.5%, 高脂组 HF)、高脂饲料+300 mg/kg 胆汁酸 (HFB1)、高脂饲料+600 mg/kg 胆汁酸(HFB2)、高脂饲料+900 mg/kg 胆汁酸(HFB3) 5 种试验饲料。将 750 尾大口黑鲈随机分为 5 组, 每个组设置 3 个平行缸, 每缸 50 尾, 进行 7 周养殖实验。结果表明: 高脂饲料显著降低大口黑鲈生长性能, 而添加胆汁酸后可改善高脂饲料对大口黑鲈生长的不利影响。饲喂高脂饲料组血浆和肝脏中甘油三酯 (TG)含量显著升高(P＜0.05)。添加胆汁酸后, 肝脏中 TG 含量显著降低(P＜0.05), 而血浆中 TG 含量在胆汁酸添加量为 900 mg/kg 时显著下降(P＜0.05)。肝脏和血浆中总胆酸(TBA)含量随着胆汁酸添加量的升高而显著增加(P＜0.05)。 胆汁酸添加量为 600 mg/kg 时, 肝脏中法尼醇 X 受体基因(fxr)表达量上调(P＜0.05), 胆汁酸合成和转运相关基因 (cyp7a1、bsep、asbt)均显著上调(P＜0.05)。同时对脂代谢相关基因表达进行检测, 发现 fxr 诱导 shp 的表达, 抑制肝脏中 srebp1 及脂肪合成相关基因(fas、acc2)的表达。此外, 胆汁酸增加肝脏中脂肪分解和 β 氧化相关基因(lpl、 hl、hsl、cpt1、acox1)的表达水平。综上所述, 高脂饲料中添加胆汁酸可改善大口黑鲈生长性能, 通过 FXR/SHP/ SREBP1 信号通路调节脂质代谢, 并促进胆汁酸合成和循环, 本研究为进一步研究胆汁酸在鱼类中的营养调控作用奠定了基础。 相似文献
8.
为探究刺鼠相关蛋白/神经肽Y (AgRP)神经元在金钱鱼应答饥饿与复投喂过程中所起的调控作用，采用反转录PCR自金钱鱼下丘脑克隆了agrp1和agrp2 2种亚型基因，并采用实时荧光定量PCR分析了2种基因在金钱鱼不同组织中的表达情况和正常投喂组(2、7 d)、饥饿组(2、7 d)、复投喂组(饥饿7 d然后复投喂3 h)金钱鱼(体质量52～60 g)下丘脑、肝脏和肠道中agrp1和agrp2基因的表达情况。序列分析结果显示，agrp1和agrp2基因的开放阅读框长度分别为429 bp和351 bp。组织表达结果显示，agrp1基因主要在下丘脑和肌肉中表达，agrp2基因主要在下丘脑和脑垂体中表达。饥饿及复投喂结果表明：下丘脑中，agrp1基因表达水平在饥饿2 d后差异不显著，饥饿7 d后显著下调，复投喂后其表达水平恢复正常；肝脏中，agrp1基因表达水平在饥饿2 d后下调，但饥饿7 d后显著上调，复投喂后其表达水平下调到正常水平；肠道中，agrp1基因表达水平在饥饿2 d后无显著差异，饥饿7 d后显著上调，复投喂后其表达水平下调到正常水平。饥饿和复投喂期间，下丘脑、肝脏和肠道中agrp... 相似文献
9.
为探究不同投喂频率对脊尾白虾(Exopalaemon carinicauda)生长的影响, 确定脊尾白虾养殖适宜投喂频率, 本研究分析了在不同投喂频率下脊尾白虾眼柄和肝脏中的生物钟基因表达节律变化, 评估了不同投喂频率对脊尾白虾生物钟系统同步性的影响, 并开展了生长及肌肉组成的同步养殖验证。结果表明: 在投喂频率为＜3 次/d 时, 生物钟基因的表达节律并没有随着投喂频率的改变而发生变化, 无论在眼柄或肝脏中均表现出相似的表达周期及表达顶相, 且各自的表达量间也无显著性差异变化。然而, 当投喂频率增加到 4 次/d 时, 肝脏中部分生物钟基因的表达节律发生了显著变化, 表现为表达周期改变、相位明显偏移及表达量变化。其中, 投喂频率为 3 次/d 时, 脊尾白虾眼柄与肝脏中生物钟基因表达节律的同步性最高。生长结果也显示, 脊尾白虾的生长性能随投喂频率升高(从 1 次/d 至 3 次/d 时)而升高, 3 次/d 时达到最高, 其特定生长率及增重率分别为(6.65±0.98)%/d 和(199.46±5.42)%。同时, 随着投喂频率升高, 脊尾白虾肌肉组织中的粗蛋白及粗脂肪含量也呈现上升趋势, 在 3 次/d 时达到最高, 分别为(19.98±0.04)%和(1.88±0.23)%。投喂频率对脊尾白虾肝脏中生物钟基因的表达节律有重要影响, 表明该因素对重置或调控脊尾白虾外周生物钟系统有一定的牵引作用。 相似文献
10.
获得了草鱼脂蛋白脂酶(lipoprotein lipase, LPL)部分cDNA序列（GenBank注册号为FJ612596）,并进行了序列同源性分析;采用半定量反转录聚合酶链式反应（SQ-RT-PCR）方法,检测了LPL基因在草鱼不同组织和不同发育阶段脂肪细胞中的表达状况;研究了饥饿和再投喂对草鱼肝胰脏LPL基因表达的影响。结果显示,所获得的草鱼LPL部分cDNA序列长度为360 bp,与其它物种的同源性为70%~89%; LPL基因在肝胰脏、肌肉、心脏、鳃、腹腔脂肪组织中均表达,其中在腹腔脂肪组织中表达丰度最高,在鳃中表达丰度最低;在成熟脂肪细胞中的表达丰度显著高于基质脉管组分（stromal vascular fraction,SVF）细胞;草鱼LPL基因表达水平在饥饿48 h后显著升高,再次投喂后12 h,回复到0 h的表达水平。研究表明,草鱼LPL在不同组织及脂肪细胞分化的起始和终末阶段均有表达,显示其在草鱼不同组织和脂肪细胞分化中具有重要作用,同时,其表达水平受营养状况的调控。论文首次克隆得到草鱼LPL基因部分cDNA序列,并对其进行了表达分析,研究结果可为LPL在鱼类脂质代谢中的作用研究提供参考和依据。 相似文献
11.
为了解黑棘鲷(Acanthopagrus schlegeli)在大亚湾生态系统食物网结构中的地位和作用, 2018 年 3 月至 2019 年 1 月逐月在大亚湾采集黑棘鲷样本, 分析黑棘鲷的食性组成、摄食强度、生态位宽度以及食性随季节和体长变化的趋势。结果表明, 大亚湾黑棘鲷饵料生物组成主要包括藤壶、鱼类、贝类、蟹类、虾类、星虫类、头足类、 水生植物等 8 个类群, 相对重要性指数百分比(IRI%)表明藤壶是最重要的饵料类群(IRI%为 42.41%), 其次依次是鱼类、贝类、蟹类、虾类、星虫类、头足类和水生植物。大亚湾黑棘鲷全年均有摄食, 摄食强度随季节变化显著, 其中胃饱满指数以春、冬季较高, 夏、秋季较低; 而空胃率则以夏季显著高于其他季节。不同季节食性差异明显, 春季主要以藤壶为食, 夏季主要以鱼类为食, 秋季主要以贝类为食, 冬季则主要以藤壶和鱼类为食, 影响食性组成随着季节变化的主要因子为水温、食物资源的可获得性等; 黑棘鲷体长越长, 越倾向于摄食大个体饵料, 摄食强度也越大, 营养生态位宽度先宽后窄。本研究结果将为今后黑棘鲷的保护和人工养殖提供理论依据。 相似文献
12.
The lack of specific compound diets for cephalopods is limiting the industrial development of some species. In this study, four agglutinated moist diets were tested in individually reared Octopus vulgaris (979 ± 151 g) for 8 weeks. All diets were based on bogue Boops boops, accidentally reared in fish farms (aquaculture by‐product), and agglutinated with alginate and calcium. One diet was based exclusively on bogue fillets, two on bogue fillets complemented with meat from two crab species (Portunus pelagicus, Grapsus grapsus) and the last one on bogue and G. grapsus meals. As a control diet, bogue and P. pelagicus were supplied fresh on alternate days. All diets induced similar feed intake (2.1–2.6% day?1). However, the meal‐based diet induced negative growth in comparison with the control and the other agglutinated diets (0.80–0.85% day?1). Higher lipid content in agglutinated diets (28–30% dw) in comparison with the control diet (16% dw) led to higher protein retention in muscle. These results underline the inadequacy of traditional meals in diets for cephalopods and that the inclusion of crab meat did not increase feeding rates and growth in O. vulgaris. The dietary fatty acid, with high levels of oleic and linoleic acid and low levels of ARA, clearly reflected in digestive gland, while only decreasing ARA and increasing EPA levels were observed in muscle, with no apparent negative effect on growth. 相似文献
13.
Jesús Cerezo Valverde Silvia Martínez-Llorens Ana Tomás Vidal Miguel Jover Carmen Rodríguez Juán Estefanell Joan I. Gairín Pedro Miguel Domingues Carlos J. Rodríguez Benjamín García García 《Aquaculture International》2013,21(2):413-433
The amino acid composition and protein levels of three species of cephalopods (Octopus vulgaris, Loligo gahi and Todarodes sagittatus), the natural diets of common octopus (O. vulgaris) and different kinds of meals were determined in order to optimise the content of these nutrients in artificial feeds. Arginine, leucine and lysine were the most abundant essential amino acids in cephalopods, while glutamate and aspartate represented the main non-essential amino acids. Arginine and leucine were the limiting amino acid in most samples, with maximum Chemical Score values for mussel (79–98 %), squid (84 %) and crustaceans (65–91 %); medium for fish (41–70 %); and minimum for meals (29–64 %). Mussel, squid, crustaceans and fish showed a high essential amino acid index according to Oser (OI: 88–99 %) suggesting a suitable amino acid balance. The protein from animal meals (fish and krill) covered all the essential amino acids except arginine and lysine in fish meal. The vegetable meal presented the worst amino acid balance (OI: 74–89 %) with several deficiencies in essential amino acids, including arginine, threonine, lysine and methionine. Supplementation with arginine or leucine and protein complementation of crustaceans and bivalves with fish or animal meal are proposed as alternatives for improving the performance of protein in feed for cephalopods. 相似文献
14.
Plasma insulin, glucagon, glucagon-like peptide (GLP) and glucose were measured in samples taken from rainbow trout,Oncorhynchus mykiss. (1.5 years of age) before feeding and at selected times up to 9 days after feeding. The feed contained 21.7% carbohydrate (65% digestibe) in the dry matter. The fish responded to feeding with an elevated plasma insulin level (p<0.005) 0.5 h post-feeding, which may account for the unchanged plasma glucose levels. Twentyfour hours after feeding, plasma insulin level had returned to prefeeding levels, while 4–9 days after feeding, a significant reduction compared to pre-feeding levels was observed (p<0.001). During this period plasma glucose levels remained unchanged. The corresponding plasma glucagon or GLP levels showed no significant elevation in response to starvation, the plasma GLP concentration was even significantly reduced on days 4–9 post-feeding (p<0.01–0.001).Atlantic salmon,Salmo salar, (3.5 years of age) fed a calculated satiation ration (RL=100) throughout their lifetime had, in addition to a higher body weight, significantly higher plasma insulin (p<0.005) glucagon (p<0.0001) and GLP levels (p<0.0001) than fish fed half the satiation ration. The plasma glucose levels were, however, not significant different between the groups. 相似文献
15.
以东海沿海捕获的野生真蛸(Octopus sinensis)为实验材料,用含秋水仙素终浓度为0.005%的海水活体暂养的方法,取鳃和肾脏细胞,利用热滴片法制备染色体标本,对其核型进行分析。结果显示,真蛸的二倍体染色体条数为60条,核型公式为2n=14 m+26 sm+12 st+8 t,其染色体臂数(NF)为100。未发现带有随体和次溢痕的染色体和异型染色体,推断真蛸可能为常染色体性别决定类型。本研究可为蛸属的细胞遗传学研究及真蛸种质鉴定和资源保护提供基础资料和参考依据。 相似文献
16.
Masafumi Amano Noriko Amiya Takehiko Yokoyama Yoko Takakusaki Hiroyuki Minakata 《Fisheries Science》2011,77(6):953-959
We have developed a time-resolved fluoroimmunoassay (TR-FIA) for octopus gonadotropin-releasing hormone (oct-GnRH) to determine
the profiles of oct-GnRH peptide levels in cephalopods. The sensitivity and the intra-assay and inter-assay coefficients of
variation were 4.9 pg/well and 6.8 (n = 10) and 2.7% (n = 5), respectively. Anti-oct-GnRH antibody was tested on all known forms of GnRH and found to cross-react with lamprey GnRH-II
(27.1%), annelid GnRH (3.36%), tunicate GnRH-I (0.92%), dogfish GnRH (0.51%), and scallop Patinopecten yessoensis GnRH (0.05%). The displacement curve obtained for serially diluted brain extracts of three cephalopods, the spear squid Loligo bleekeri, swordtip squid Loligo edulis, and North Pacific giant octopus Octopus dofleini, paralleled the oct-GnRH standard curve. The presence of oct-GnRH in the central nervous system (CNS) of these cephalopods
was further examined by a combination of reverse-phase high performance liquid chromatography and oct-GnRH TR-FIA. CNS extracts
from these cephalopods showed peaks with retention times similar to that of synthetic oct-GnRH. These results indicate that
this novel oct-GnRH TR-FIA is widely applicable for oct-GnRH measurement in cephalopods. 相似文献
17.
Iker Uriarte Jos Iglesias Pedro Domingues Carlos Rosas María T. Viana Juan C. Navarro Pedro Seixas Erica Vidal Alberto Ausburger Sandra Pereda Flix Godoy Kurt Paschke Ana Farías Alberto Olivares Oscar Zuiga 《Journal of the World Aquaculture Society》2011,42(6):735-752
The increasing market demand for cephalopods and the experiences obtained with different species has boosted the interest in developing their culture in Latin America. In 2008, an international workshop was held in Puerto Montt, Chile, with 14 experts in experimental cephalopods aquaculture from Brazil, Chile, Spain, and Mexico. Several topics were approached within the holobenthic species Octopus maya and the merobenthic species Enteroctopus megalocyathus, Octopus vulgaris, and Robsonella fontaniana. Part of the conclusions demonstrated that the two greatest difficulties for their production were survival of paralarvae for merobenthic species, and survival of early juveniles for holobenthic species. Besides, there is a need to study the endogenous and exogenous factors affecting health and nutritional status of embryos, paralarvae, and juveniles. These stages, which may limit the culture, should be extensively studied in order to develop the appropriate environmental conditions and culture systems for the physiological and behavioral requirements, from egg incubation up to juveniles to reach a grow‐out phase. 相似文献
18.
J. Sunde S.A. Eiane A. Rustad H.B. Jensen J. Opstvedt E. Nygård G. Venturini & K. Rungruangsak-Torrissen 《Aquaculture Nutrition》2004,10(4):261-277
The responses of the digestive proteases trypsin and chymotrypsin and protein metabolism to differences in feed protein quality were investigated in Atlantic salmon (Salmo salar L.). Two sets of experimental feeds were produced. Each set of high and low quality feeds was provided to either 150 g or 2 kg salmon. Protein in the high quality feeds had significantly higher percentages of free (reactive) sulphydryl (SH) groups than the corresponding feeds based on low quality meals. After 90 days feeding, groups given high and low quality feeds did not differ in their specific growth rates (SGR) in either experiment. However, feed conversion efficiency (FCE) was significantly different between the high and low quality feed groups in 2 kg salmon, where the difference between the high and low feed protein qualities was larger, 10% versus 4% SH/[SH + (S–S)] in 150 g salmon. Higher FCE was preceded by significantly higher trypsin and chymotrypsin specific activities on day 60. SGR, in general, changed after the first month and was stable during the last 2 months in both experiments. Concurrently, both trypsin (T) and chymotrypsin (C) decreased with an increased activity ratio of trypsin to chymotrypsin (T/C ratio), and resulting in significantly lower T/C ratio on day 90 in salmon feeding on high quality feeds in both sizes of fish. Differences in FCE were associated with significant differences in levels of total free amino acids (TFAA) in the plasma and the white muscle, as well as in the ratio of essential to non‐essential free amino acids (EAA/NEAA ratio), free hydroxyproline, and RNA in the white muscle. Interestingly, after 3 days starvation (day 93), 5–7 h postprandial EAA/NEAA ratio in the plasma was significantly lower in the high quality diet groups in both experiments. Trypsin specific activity inversely correlated with muscle TFAA levels in 2 kg salmon, concurrent with higher muscle levels of RNA, lower free hydroxyproline and higher FCE in fish fed higher quality diets. 相似文献
19.
Zhi Luo Yong-Jian Liu Kang-Sen Mai Li-Xia Tian Xiao-Ying Tan Jin-Fang Shi 《Journal of the World Aquaculture Society》2006,37(1):32-40
An experiment was conducted to determine effects of feeding levels on growth performance, feed utilization, body composition, and apparent digestibility coefficients (ADCs) of nutrients for juvenile grouper Epinephelus coioides (initial weight, 10.31 ± 0.36 g). Grouper were fed a practical diet from 0 (starvation) to 3.5% (at 0.5% increments) body weight per day (bw/d) for 8 wk. ANOVA indicated that growth performance, feed utilization, body composition, and ADCs of dry matter, protein, and energy were significantly (P < 0.05) affected by feeding levels. Survival was the lowest for the starvation group and for fish fed a ration of 0.5% bw/d. Final mean body weight, weight gain (WG), specific growth rate, and metabolic growth rate increased with feeding rate from 0 to 2.5% bw/d (P < 0.05) and showed no significant differences above the level (P > 0.05). Feed conversion rate was significantly lower at a feeding level of 2.0% bw/d than above and below the level (P < 0.05). Protein efficiency ratio was markedly highest at the 2.0% bw/d ration level (P < 0.05). Lipid contents of whole body, muscle, and liver increased with increasing feeding rates from 0 to 3% bw/d and showed a slight decline at the feeding level of 3.5% bw/d. Protein contents of whole‐body composition, muscle, and liver remained relatively stable with the different ration amount with the exception of fish fed a ration of 0.5% bw/d, at which grouper possessed significantly lower body protein concentration (P < 0.05). Condition factor, viscerosomatic index, and hepatosomatic index were the lowest for fish fed 0.5% bw/d and tended to increase with the increasing feeding levels. ADCs of dry matter, protein, and energy decreased with increasing feeding levels from 0 to 2.5% bw/d and then remained relatively constant over the level. Based on the broken‐line regression analysis using WG data, the optimum and maintenance feeding levels for grouper were 2.5% bw/d and 0.25% bw/d, respectively. 相似文献
20.
为探究延迟首次投喂对乌江中华倒刺鲃(Spinibarbus sinensis)仔鱼补偿生长、消化酶活性及饵料日转化率的影响,对肠道贯通后的仔鱼进行了不同饥饿天数(H0、H1、H3、H5、H7、H9、H11)后补偿投喂17 d的实验。结果显示,全长和体重的损失率随饥饿时间的延长而增加。补偿投喂后,全长补偿率在H9组以后明显下降,体重补偿率在各实验组间无明显差异。各组全长和体重的特定生长率都呈波动性变化趋势,且实验后期各实验组都大于正常组都存在显著性差异。全长、体重及特定生长率的变化表明该饥饿仔鱼补偿投喂后能完成部分补偿生长。饥饿处理中,淀粉酶、碱性磷酸酶和胰蛋白酶随饥饿时间都呈下降趋势,脂肪酶呈先上升后下降趋势,补偿投喂后,除了淀粉酶呈先上升后下降外,其余三种酶都呈上升趋势。各组在饥饿处理下消化酶活性在实验后期与正常组存在显著差异,再投喂后与正常组差异不显著。各组在再投喂后的饵料日转化率随补偿时间呈不规则上升,但都无法恢复到正常投喂水平。综上,延迟首次投喂对中华倒刺鲃仔鱼补偿生长、消化酶活性及饵料转化都存在不同程度的影响。 相似文献