轮虫、卤虫无节幼体及蝇蛆三种开口饵料对黄颡鱼仔鱼生长、存活及免疫酶活性的影响

在水温(25±0.5)℃下,将10 000尾4日龄的体长(0.25±0.004)cm的全雄黄颡鱼Pelteobagrus fulvidraco仔鱼放入长2m×宽1.4m×水深30cm的孵化槽中,投喂轮虫、卤虫无节幼体和蝇蛆三种开口饵料,研究不同开口饵料对黄颡鱼仔鱼生长、存活率以及免疫相关酶活性的影响。结果表明,饲养3d时,投喂卤虫无节幼体组仔鱼的体质量显著大于轮虫组(P0.05),而投喂蝇蛆组仔鱼的体质量介于二者之间,且与两组无显著差异(P0.05);7d后,投喂蝇蛆组仔鱼体质量最大,显著大于后两组(P0.05),卤虫无节幼体组次之,轮虫组最小;投喂蝇蛆组仔鱼的存活率最高,投喂蝇蛆组仔鱼酸性磷酸酶(ACP)、碱性磷酸酶(AKP)和溶菌酶(LZM)活力显著高于其他两组(P0.05),而其他两组仔鱼这三种酶活力没有显著影响。认为与轮虫、卤虫无节幼体相比,蝇蛆是一种更适宜黄颡鱼仔鱼培育的开口饵料。     

卤虫无节幼体的营养强化对半滑舌鳎稚鱼生长、消化酶及相关激素水平的影响

通过投喂经蛋氨酸及裂壶藻强化的卤虫,研究其对半滑舌鳎稚鱼(初始体长1.67±0.14cm)生长性能、主要消化酶活性(淀粉酶、胃蛋白酶、类胰蛋白酶)、碱性磷酸酶活性及胆囊收缩素(CCK)、甲状腺素(T4)、三碘甲状腺原氨酸(T3)和皮质醇浓度的影响.试验设3个实验组(蛋氨酸组、裂壶藻组和蛋氨酸加裂壶藻组),分别投喂经蛋氨酸、裂壶藻及蛋氨酸十裂壶藻强化的卤虫,对照组投喂未经强化的卤虫.试验进行16d,每4d取样1次.结果显示,裂壶藻组的体长和体重在试验结束时处于最高水平,体重显著高于对照组(P＜0.05),体长在12d时显著高于其他组(P＜0.05).裂壶藻组碱性磷酸酶活力在16d时显著高于蛋氨酸组和对照组,类胰蛋白酶活力在16d时显著高于其他组(P＜0.05),T3含量在12d时显著高于蛋氨酸组及对照组,T4水平在12d时显著高于对照组(P＜0.05).蛋氨酸加裂壶藻组淀粉酶活力在12d时显著高于蛋氨酸组(P＜0.05).对照组的CCK含量在4d时显著高于蛋氨酸组和蛋氨酸加裂壶藻组(P＜0.05),12d显著高于3个实验组,16d时显著高于裂壶藻组(P＜0.05).蛋氨酸组的皮质醇含量在4d时显著低于其他3个试验组(P＜0.05),8d和16d时显著低于对照组及蛋氨酸加裂壶藻组(P＜0.05).其碱性磷酸酶、淀粉酶活力及T4和T3水平在试验前期都较高,说明蛋氨酸强化的卤虫投喂对半滑舌鳎稚鱼的生长及激素水平有较微弱的促进作用,可能是由于卤虫无节幼体含有的蛋氨酸基本可以满足鱼体生长需要.     

不同饵料对海蜇幼体生长、消化酶、抗氧化和免疫酶活力的影响

本研究旨在探讨不同饵料对海蜇(Rhopilema esculentum)幼体生长、消化酶、抗氧化酶和非特异性免疫酶活力的影响。实验设置4个饵料组:小球藻组、虾片(对虾开口饵料)组、卤虫无节幼体组和混合组(卤虫无节幼体和虾片等比例混合),养殖实验持续进行30 d。结果显示:混合组和卤虫无节幼体组海蜇的增重率(WGR)和特定生长率(SGR)都显著高于其他各组(P<0.05);混合组海蜇胃丝的蛋白酶活力显著高于小球藻组和虾片组(P<0.05);虾片组海蜇口腕的淀粉酶活力显著高于其他各组(P<0.05);各饵料实验组的脂肪酶活力均显著高于初始组(P<0.05);在海蜇的体腔液中,混合组和卤虫无节幼体组的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、总抗氧化能力(T-AOC)和溶菌酶(LZM)活力均显著高于其他各组(P<0.05)。研究表明,混合组和卤虫无节幼体组可以显著促进海蜇的生长,增强海蜇的抗氧化能力和免疫酶活力。     

云斑尖塘鳢转饵期仔鱼生长和存活率的研究

在水温(30±1)℃条件下对人工孵化的云斑尖塘鳢(Oxyeleotris marmorata)仔鱼进行转饵期不同投喂策略实验,对仔鱼生长和成活情况进行了研究,设计5个投喂组:轮虫投喂组(A组);70%轮虫+30%卤虫投喂组(B组);50%轮虫+50%卤虫投喂组(C组);30%轮虫+70%卤虫投喂组(D组);卤虫(幼虫)投喂组(E组)。结果显示:云斑尖塘鳢仔鱼对卤虫的摄食强度随卤虫在饵料中比例的升高而增大,其对混合饵料中轮虫和卤虫的摄食强度的比值(Ir/Ia)随食物组成的变化发生相应的变化。以轮虫-卤虫不同比例的混合饵料投喂时,D组仔鱼的增长率、增重率最高,可存活率不足50%,高于E组,显著低于其它各组;C组仔鱼生长指标略低于D组,但存活率为(74.00±2.29)%,综合指标显著好于其它各组。当混合饵料中轮虫和卤虫各占50%时,10日龄开始投喂组仔鱼的全长(13.07±0.13)mm,特定生长率(10.25±0.37)%/d,存活率(82.14±0.72)%,综合生长指标最好。结果表明,云斑尖塘鳢仔鱼转饵期进行联合投喂的最佳饵料比例为50%轮虫+50%卤虫,最佳转饵时间为10日龄。     

微颗粒饲料中添加消化酶对半滑舌鳎仔、稚鱼生长和消化酶活性的影响

以初始体长16.61±2.33 mm的半滑舌鳎仔鱼(孵化后第20天)为实验对象,在室内进行为期25d的摄食生长实验.在基础饲料中分别添加0、0.05%和0.1%的胰蛋白酶配制3组微颗粒饲料,同时,以活饵料(卤虫)作为对照组,研究饲料中添加不同剂量的消化酶对半滑舌鳎仔鱼生长和消化酶活性的影响.实验结果表明,添加胰蛋白酶组的仔、稚鱼体重明显高于未添加组(P＜0.05),但是低于活饵料组(P＜O.05),添加胰蛋白酶组之间没有显著性差异(P＞0.05).成活率的结果显示,活饵料组明显地高于微颗粒饲料组(P＜0.05),但是3个微颗粒饲料组之间没有显著性差异(P＞0.05).消化酶分析结果表明,除了碱性磷酸酶以外,不同饵料对蛋白酶、淀粉酶和脂肪酶的活性均没有影响.结果表明,在饲料中添加外源性消化酶可以显著地提高半滑舌鳎仔、稚鱼的生长,对于体内消化酶的影响却不显著,其中的机制有待进一步研究.     

芽孢杆菌微生态制剂对灰海马幼体生长、成活率及消化酶活力的影响

通过给灰海马(Hippocampus erectus Perry)初生幼体口服卤虫包膜的芽孢杆菌微生态制剂,探讨其对海马幼体生长、成活率及消化酶活力的影响。共计3批初生的灰海马幼体(3对亲本一次产出的全部幼体),每批平均分为两组,分别作为试验组和对照组。3批幼体作为3个重复组,以排除初生幼体质量不同引起的差异。试验组投喂用芽孢杆菌微生态制剂处理过的卤虫幼体,对照组投喂未经芽孢杆菌微生态制剂处理的卤虫幼体,试验时间为25 d。试验结束时,试验组灰海马幼体体长和体长增量与对照组无显著差异;体质量方面,仅第3批中试验组显著高于对照组(P＜0.05),其它两批无显著差异;3批次试验组灰海马幼体的成活率均显著高于对照组(P＜0.05);消化酶方面,试验组与对照组间除第3批试验灰海马幼体的脂肪酶活力及第1批试验灰海马幼体的蛋白酶活力无显著差异外,其它批次中试验组灰海马肠道脂肪酶、蛋白酶和淀粉酶的活力均显著高于对照组(P＜0.05)。结果表明,口服芽孢杆菌微生态制剂能够显著提高人工养殖灰海马幼体的成活率及肠道消化酶活力。     

饵料结构对池塘河蟹生长性能及营养积累的影响

通过全程投喂冰冻小鱼、全程投喂颗粒饲料及颗粒饲料和冰鱼混合投喂的三种方式,对平均规格达(6.25±0.31)g/只,投喂280 d后,采样测定生长指标、肝胰腺指数、性腺指数。经单因素方差分析结果显示饲料组及混合组的平均规格、成活率、显著大于冰鱼组(P0.05),特定生长率在组间差异不具有统计学意义(P0.05),冰鱼组的肥满度及饵料系数远大于其他两组,且差异具有统计学意义(P0.05)。颗粒饲料组投喂下的雌、雄蟹肝胰腺指数最高,冰鱼组的雌、雄蟹性腺指数最高,由此可见,颗粒饲料组仍有生长的空间。从成本核算来看,混合组效益最高,颗粒饲料组其次,冰鱼组最小,从投入产出比来看,颗粒组最高。综上所述,全程投喂颗粒饲料对河蟹生长及营养积累有促进作用,具有更广阔的应用前景。     

长薄鳅开口饵料的研究

为寻找合适的长薄鳅仔鱼开口饵料,分别以卤虫、枝角类、蛋黄、卤虫+蛋黄、枝角类+蛋黄、卤虫+光合细菌、枝角类+光合细菌等7种不同的饵料对刚脱膜4d的仔鱼进行了饲喂试验.结果表明:(1)不同饵料对长薄鳅仔鱼的生长具有显著影响(P＜0.05),其中,枝角类+光合细菌组生长最快,绝对增重率和特定增重率分别为4.63±0.075 mg/d和19.02±0.404 ％/d;蛋黄组生长最慢,绝对增重率和特定增重率与其他各组差异显著(P＜0.05).(2)第1周投喂卤虫+光合细菌组合的饵料,仔鱼的成活率最高,为96％;蛋黄组的最终成活率最低,只有34％,且该组仔鱼个体发育较为缓慢,与其他各组差异显著(P＜0.05).根据试验结果,建议在水泥池育苗的条件下,对刚脱膜4d的长薄鳅仔鱼,第1周投喂卤虫+光合细菌,后期投喂枝角类+光合细菌,以提高仔鱼的成活率和成长率.     

不同饵料对胭脂鱼生长和肠道消化酶活性的影响

研究了不同饵料(卤虫、饲料、水蚯蚓、水蚯蚓+饲料)对胭脂鱼生长和消化酶活性的影响。在水温(18±2)℃将初始体质量为(6.60±0.40)g的胭脂鱼随机分成4组,每组3个重复,每个重复放养10尾鱼,分别饲喂卤虫、饲料、水蚯蚓、水蚯蚓+饲料,试验周期56d。试验结果表明,水蚯蚓+饲料混合组和水蚯蚓组生长效果最佳,混合组优于水蚯蚓组(P0.05),饲料组和卤虫组次之,饲料组优于卤虫组(P0.05);肠道消化酶活性卤虫组饲料组水蚯蚓组混合组,卤虫组和饲料组3种消化酶活性均最低,水蚯蚓组与水蚯蚓+饲料混合组差异显著(P0.05)。     

卤虫在不同饵料培养介质中的生长规律

以啤酒酵母和单胞藻为投喂饵料，新疆艾比湖卤虫（Artemia parthenogenetica)为投喂对象，建立三个实验组分别进行研究，观察在不同饵料条件下艾比湖卤虫的生长，探讨不同饵料对卤虫的生长、成活的影响。通过对卤虫体长和存活率的测量，建立了卤虫在不同饵料情况下的生长方程、生长曲线和存活率曲线，并通过对方程和曲线的分析获得以下结论：投喂单胞藻组卤虫的生长最慢，存活率最低25表面以后全部死亡；投喂酵母组卤虫生长最快，在0≤t≤42.6时体长值最高，存活率较低，投喂单胞藻和酵母的混合饲料组卤虫的前期生长次于酵母组，后期生长超过之，存活率较高且成熟个体产虫量和产卵量也多于酵母组。     

Effect of Diet Processing Method and Ingredient Substitution on Feed Characteristics and Survival of Larval Walleye, Sander vitreus

Two methods were developed for the production of larval fish diets. The first method, microextrusion marumerization (MEM), has been tested in laboratory feeding trials for many years and produces particles that are palatable and water stable. The second method, particle‐assisted rotational agglomeration (PARA), produced diets that have lower density than diets produced by MEM. Each method was used to produce diets in the 250‐ to 400‐ and 400‐ to 700‐μm range and compared with a reference diet (Fry Feed Kyowa * [FFK]) for feeding larval walleye in two experiments. The effect of substituting 4% of the fish meal with freeze‐dried artemia fines was also investigated. In the first experiment, 30‐d survival was greater (P < 0.05) for fish fed a diet produced by PARA without Artemia (49.1.0%) than for fish fed the same diet produced by MEM (27.6%). The addition of Artemia to a diet produced by MEM did not increase survival of larval walleye. Fish fed the reference diet had 24.4% survival. In the second experiment, there was an effect of both processing method and Artemia supplementation, and an interaction of these effects, on survival. Fish fed a diet produced by PARA without Artemia supplementation had 48.4% survival, and fish fed the same diet produced by MEM had only 19.6% survival. Inclusion of 4% freeze‐dried Artemia improved (P < 0.04) survival of fish fed MEM particles but not those fed PARA particles. Fish fed FFK had greater weight gain than fish fed other diets in both experiments. Data indicate that the PARA method of diet processing produces smaller, lower density particles than the MEM process and that diets produced by the PARA process support higher survival of larval walleye with low capital and operating costs.     

光照对红条鞭腕虾繁殖性能及饵料对其幼体生长发育的影响

为了深入了解光照对红条鞭腕虾(Lysmata vittata)亲虾抱卵情况的影响,本研究通过将正常光照组(12L∶12D)亲虾的抱卵率与全暗(黑)组进行对比,发现正常光照组红条鞭腕虾亲虾抱卵率为(95.8±3.6)%,而全暗(黑)组的抱卵率为0,正常光照组亲虾的抱卵率显著高于全暗(黑)组(P0.05),表明适宜的光照强度对红条鞭腕虾亲虾抱卵行为起到促进作用。本研究还对比分析了投喂不同生物饵料对红条鞭腕虾溞状幼体成活率和生长发育周期的影响。结果发现,投喂丰年虫(Artemia nauplii)和蒙古裸腹溞(Moina mongolica Daday)混合组的溞状幼体成活率为(38.3±2.3)%,幼体经过25～29 d全部发育成仔虾;而单一投喂丰年虫组的溞状幼体成活率为(26.8±4.9)%,幼体经过37～41 d全部发育成仔虾;混合组的溞状幼体成活率显著高于单一组(P0.05),且其幼体的生长周期也明显短于单一组,表明投喂丰年虫和蒙古裸腹溞混合饵料比只投喂丰年虫饵料更有利于幼体的存活和发育。此外,本研究还观察和详细描述了红条鞭腕幼体发育过程的形态和结构变化特征,并将它分为溞状幼体1～9期等9个不同时期,幼苗经过9期溞状幼体期后通过蜕皮最终变态为红条鞭腕虾仔虾。本研究对丰富鞭腕虾属虾类的生殖生物学理论和开展其人工繁育研究具有重要的指导意义。     

Use of commercial Artemia replacement diets in culturing larval American lobsters (Homarus americanus)

This work reports on the successful incorporation of commercial formulated Artemia replacement diets as 50% of a larval American lobster diet. Combination diets of either live Artemia nauplii or frozen adult n-3 fatty acid enriched Artemia with a rotation of three commercial formulated diets resulted in equivalent survival to stage IV (19–25%), postlarval size and subsequent early juvenile performance compared to an Artemia nauplii plus frozen Artemia combination diet. A 100% formulated diet resulted in reduced larval survival (6%) and postlarval size, while a larval diet of 100% frozen adult Artemia resulted in reduced postlarval quality and early juvenile performance. The much lower price of the formulated diets compared to the prices of Artemia nauplii and frozen Artemia makes its inclusion in the lobster larval diet the most cost-effective diet choice.     

饲料中花生四烯酸含量对刺参生长性能、抗氧化能力及脂肪酸代谢的影响

为探究饲料中添加花生四烯酸(arachidonic acid,ARA)对刺参(Apostichopus japonicus)生长性能、抗氧化能力及脂肪酸代谢的影响,选用初始体重为(10.78±0.06)g的刺参为研究对象,以鱼粉和发酵豆粕为主要蛋白质源,小麦粉为主要糖源制作基础饲料,通过在基础饲料中添加不同比例的ARA-纯化油,制成ARA含量分别为0.02%(对照组)、0.17%、0.36%、0.51%、0.59%和0.98%(占饲料干重)的6组等氮等脂的实验饲料,在室内循环水养殖系统进行为期56 d的养殖实验。结果表明,随着饲料中ARA含量的升高,刺参增重率(weight gain rate,WGR)呈先上升后降低的趋势,0.36%和0.51%ARA饲料组刺参WGR显著高于其他处理组(P0.05),刺参的特定生长率(specific growth rate,SGR)和饲料效率(feed efficiency,FE)与WGR具有相同的变化趋势;刺参体壁粗脂肪含量随饲料ARA含量升高呈先降低后升高的趋势,在0.51%ARA饲料组含量最低,且显著低于对照组与0.98%ARA饲料组(P0.05);同时,随饲料中ARA含量的提高,刺参体壁中ARA和n-6多不饱和脂肪酸(n-6 polyunsaturated fatty acids,n-6 PUFA)含量呈显著上升趋势,而二十碳五烯酸(eicosapentaenioc acid,EPA)、二十二碳六烯酸(docosahexaenoic acid,DHA)和n-3多不饱和脂肪酸(n-3 polyunsaturated fatty acids,n-3 PUFA)含量显著降低(P0.05);抗氧化能力方面,0.36%和0.51%ARA饲料组刺参肠道中超氧化物歧化酶(superoxide dismutase,SOD)、过氧化氢酶(catalase,CAT)和总抗氧化能力酶(total antioxidant capacity enzyme,T-AOC)活性均显著高于对照组与0.98%ARA饲料组(P0.05),而肠道丙二醛(malondialdehyde,MDA)含量呈相反的变化趋势(P0.05);刺参肠道中脂肪酸合成酶(fatty acid synthase,FAS)和乙酰辅酶A羧化酶(acetyl-Co A carboxylase,ACC)活性随饲料ARA含量的升高呈显著降低趋势(P0.05);刺参肠道中肉毒碱棕榈酰转移酶-1(carnitine palmitoyltransferase-1,CPT-1)活性随饲料ARA含量升高呈先升高后降低的趋势(P0.05)。研究表明,在本实验条件下,饲料中添加适量ARA(0.36%~0.51%)能够对刺参生长、抗氧化能力起到一定的促进作用,同时结果显示,饲料ARA含量会对刺参肠道内脂肪酸代谢产生一定的影响。     

Lipid enrichment for Senegalese sole (Solea senegalensis) larvae: effect on larval growth, survival and fatty acid profile

Results from three larval Senegalese sole (Solea senegalensis) feeding trials using non-enriched Artemia and Artemia enriched with Super HUFA®, Arasco®, sunflower oil and microalgae are presented and the effects on larval survival, growth and fatty acid (FA) composition are reported. The FA profile of Senegalese sole eggs was analysed to gather information about the nutritional requirements of the early larval stages and a quite high DHA/EPA ratio (4.3) was found. However, there was no evidence of a high dietary demand for DHA or EPA, given that no relationship was found between dietary HUFA concentration and larval growth and survival. When larvae were fed non-enriched Artemia a significantly better growth and comparable survival were obtained than with Artemia enriched with Super HUFA® (containing the highest HUFA level and DHA/EPA ratio). The FA profiles of the larvae generally reflected those of their diets. DHA was an exception, as it was present in high proportions, even in larvae fed DHA-deficient prey. Total FAME concentration decreased during larval development, with SFA, MUFA and PUFA being equally consumed; HUFA appeared to be less used, with its relative concentration being either kept constant (particularly EPA and ARA) or increased (DHA). A specific requirement for ARA in the first larval stages could not be confirmed but it was always present in considerable amounts, even in larvae fed an ARA poor diet.     

The Effect of Maturation Diets on the Reproductive Output of the White‐striped Cleaner Shrimp,Lysmata amboinensis

Aquaculture production of the cleaner shrimp Lysmata amboinensis, a high‐valued marine ornamental, has been problematic because of prolonged larval development punctuated by periods of mortality. Broodstock maturation diets have been shown to affect fecundity and offspring quality and early survival. The common practice in shrimp culture is the use of fresh frozen foods supplemented with artificial diets. The objective of the study was to identify a suitable maturation diet (natural or artificial) for L. amboinensis. Six diets, comprised of squid, mussel, adult Artemia, a commercial feed, and combinations of the aforementioned, were fed to L. amboinensis for four reproductive cycles. Broodstock fed the squid–mussel diet lost a large proportion of the eggs during incubation, with decreased larval production (P < 0.05). In contrast, broodstock fed Artemia retained the highest proportion of the egg mass; however, hatchability was poor, resulting in low larval numbers per hatch. The Artemia and squid–mussel diets produced significantly fewer larvae than the combination or commercial diets (P < 0.05). In L. amboinensis, a maturation diet consisting of natural feeds alone resulted in poor reproductive performance and partial or complete replacement with an artificial diet was feasible.     

银鲳卵黄发生期间组织中抗氧化水平的变化及饲料n-3 LC-PUFA对其的影响

研究了银鲳(Papus argenteus)肝及卵巢组织中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性、总抗氧化能力(T-AOC)及丙二醛(MDA)含量在整个卵黄发生过程中的变化情况,并分析了饲料n-3 LC-PUFA对卵黄发生期间组织中抗氧化水平的影响。分别以100%鱼油(FO组)、70%鱼油和30%大豆油(FSO组)、30%鱼油和70%大豆油(SFO组)、100%大豆油(SO组)为脂肪源,配制了4组等氮、等能及等脂的试验饲料。以1年龄雌性银鲳为试验对象,每组饲料设3重复,试验周期185 d。研究结果表明,肝与卵巢组织SOD、CAT活性、T-AOC水平及MDA含量在卵黄发生过程中均呈现逐渐升高的趋势,且卵黄发生后期各指标水平均显著高于卵黄发生前期(P0.05)。肝SOD(除SO饲料组外)、CAT活性、T-AOC水平及MDA含量在卵黄发生中期与前期之间未表现出显著性差异(P0.05),而卵黄发生中期FO与FSO饲料组卵巢SOD、CAT活性及T-AOC水平则均显著高于卵黄发生前期(P0.05)。FSO饲料组肝与卵巢SOD、CAT活性在卵黄发生过程中均为最高值,且在卵黄发生中、后期均显著高于SO饲料组(P0.05),但与FO饲料组无显著性差异(P0.05)。各饲料组间肝与卵巢T-AOC水平在卵黄发生前期均未表现出显著性差异(P0.05),而在卵黄发生后期,FO与FSO饲料组肝与卵巢T-AOC水平均显著高于SO饲料组(P0.05),但FO与FSO饲料组间无显著性差异(P0.05)。肝与卵巢中MDA含量随着饲料n-3 LC-PUFA含量的升高而呈现出升高趋势,且这种升高趋势在肝组织中表现更为明显,卵巢组织MDA含量在卵黄发生中、后期仅FO饲料组表现出显著性升高趋势(P0.05),其他各饲料组在卵黄发生各期均未表现出显著性差异(P0.05)。统计分析表明,银鲳卵黄发生过程中组织中抗氧化水平逐渐升高,适宜的饲料n-3 LC-PUFA含量(4.01%,FSO饲料组)可明显改善银鲳卵黄发生中期与后期组织中的抗氧化水平。双因素方差分析结果表明,试验饲料与卵黄发生时期对银鲳组织抗氧化水平均具有极显著性影响(P0.01),且两者对肝T-AOC水平与MDA含量存在显著性的交互作用(P0.05)。     

酵母水解物对凡纳滨对虾生长、消化酶活性和肠道形态的影响

本实验旨在研究饲料中添加酵母水解物对凡纳滨对虾(Litopenaeus vannamei)生长性能、血清生化指标、肝胰腺消化酶活性以及肠道形态的影响。酵母水解物添加量分别为0%、1%、3%和5%,配制4种等氮等脂(42.5%粗蛋白和8.5%粗脂肪)的实验饲料。选取初始体重为(1.86±0.02)g的凡纳滨对虾480尾,随机分为4组,每组4个重复,每个重复30尾,进行为期8周的养殖实验。结果表明饲料中添加5%酵母水解物组的增重率(WGR)、特定生长率(SGR)和蛋白质效率(PER)显著高于对照组(P0.05),而该组饲料系数(FCR)最低(P0.05)。对虾全虾粗蛋白含量随饲料中酵母水解物的增加而呈上升趋势,且5%酵母水解物添加组显著高于对照组(P0.05)。添加5%的酵母水解物显著提高了凡纳滨对虾血清总蛋白(TP)和甘油三酯(TG)含量,降低了谷草转氨酶(AST)和谷丙转氨酶(ALT)的活性(P0.05)。各处理组肝胰腺淀粉酶活性和对照组相比差异不显著(P0.05),但3%酵母水解物添加组的胰蛋白酶和脂肪酶活性显著高于对照组(P0.05)。3%酵母水解物添加组的对虾肠道皱襞高度和皱襞宽度显著高于对照组(P0.05),而5%添加组的微绒毛高度显著高于对照组(P0.05)。综上所述,在本实验条件下,饲料中添加3%~5%的酵母水解物能有效改善凡纳滨对虾生长性能、提高饲料利用率、促进消化吸收以及改善肠道形态学指标。     

Influence of larval co-feeding with live and inert diets on weaning the tongue sole Cynoglossus semilaevis

The tongue sole Cynoglossus semilaevis, an inshore fish in China, has showed great potential in aquaculture recently. However, poor survival was recorded during the period of weaning from live Artemia to artificial diets. In this paper, the influence of co‐feeding larvae with live and inert diet on weaning performance was described. The C. semilaevis larvae were reared at 21 ± 1 °C and fed four different feeding regimes from 6 days post‐hatching (dph): A, Artemia (10 individuals mL^?1); B, Artemia (5 individuals mL^?1); C, mixed diet (10 Artemia individuals mL^?1 and 12 mg L^?1 inert diet); and D, mixed diet (5 Artemia individuals mL^?1 and 12 mg L^?1 inert diet). Rotifers were also supplied in all cases during the first days of feeding. Mixed diets of commercial formulated feed and live prey (rotifers and Artemia) allowed larvae to complete metamorphosis, achieving similar specific growth rate (SGR) (18.5 ± 1.4% and 18.7 ± 1.6%) and survival (40 ± 7.6% and 48.5 ± 6.8%) compared with larvae fed on live feed alone (SGR of 18.3 ± 1.2%, 19.3 ± 1.9% and survival of 41.2 ± 11.3%, 38 ± 4.9%). However, in metamorphosed fish, when live feed was withdrawn on 31 dph, there was significant difference (P < 0.05) in survival and growth among treatments. Metamorphosed fish, previously fed mixture diets during larval stages, had similar survival (62.1 ± 7.6% and 62.8 ± 3.9% for regimes C and D, respectively) but higher than that obtained for fish that previously fed on live feed (49.3 ± 2% and 42.1 ± 3.9% for regimes A and B, respectively) after weaning (day 60). The SGR of weaned fish previously fed live feed was similar (3.1 ± 0.6% and 2.92 ± 0.6% for regimes A and B, respectively) but lower than that recorded for fish that was fed from day 6 to day 30 on the mixed diet (4.5 ± 1.1% and 4.9 ± 0.3% for regimes C and D, respectively). It is suggested that weaning of C. semilaevis from early development would appear to be feasible and larval co‐feeding improves growth and survival.     

添加嗜酸乳杆菌对凡纳滨对虾生长、酶活性及相关酶mRNA表达的影响

本实验旨在研究饲料中添加嗜酸乳杆菌(Lactobacillus acidophilus)对凡纳滨对虾(Litopenaeus vannamei)幼虾生长、非特异性免疫酶活性、抗病力和相关酶m RNA表达的影响。选取840尾初始均重为(0.58±0.01)g的凡纳滨对虾幼虾为研究对象,分为7个处理,每个处理3个重复。投喂添加不同比例(0%,0.1%,0.2%,0.4%,0.6%,0.8%,1.0%)嗜酸乳杆菌的饲料,养殖期8周。结果显示:添加不同比例嗜酸乳杆菌对凡纳滨对虾的成活率无显著影响(P0.05)。增重率与特定生长率随添加量的增加呈先上升后下降的趋势,但均显著高于对照组(P0.05),在0.4%组达到最大值;当添加0.2%时,饲料系数最低,其他各组显著低于对照组(P0.05),而蛋白质效率的变化规律则与饲料系数相反。血清酚氧化物酶(phenoloxidase,PO)、碱性磷酸酶(alkaline phosphatase,AKP)和酸性磷酸酶(acid phosphatase,ACP)活性随添加量的增加先升高后降低,分别为0.4%、0.1%和0.2%时,达到最大值。过氧化氢酶(catalase,CAT)、溶菌酶(lysozyme,LZM)和超氧化物歧化酶(superoxide dismutase,SOD)活性,实验组均显著高于对照组(P0.05)。实验组过氧化氢酶(CAT)m RNA表达量和溶菌酶(LZM)m RNA表达量均显著高于对照组(P0.05)。哈维弧菌(Vibrio harveyi)攻毒96 h,对虾存活率随添加量的增加显著升高(P0.05)。以增重率(weight gain rate,WGR)为判断依据,根据折线模型得出,饲料中添加0.23%嗜酸乳杆菌可显著促进凡纳滨对虾生长,并提高非特异性免疫酶活性。