几种免疫因子对九孔稚鲍免疫力的影响

选用浓度分别为5×10^-6、10×10^-6、0．5×10^-6、1×10^-6的维生素B6（维生素类）、益母草膏（中草药类）、腐殖酸（天然螯和剂）和大蒜素（免疫药物）4种制剂,采用浸浴的方法,对11-39日龄的九孔稚鲍（Haliotis diversicolor supertexta）进行免疫刺激。试验期间每两天换水、补药一次,以维持各组原有的药物浓度,同时对稚鲍的脱板情况进行计数;最后取样测定各组幼体酚氧化物酶、溶菌酶的活性。试验结果表明。各药物组的酚氧化物酶和溶菌酶含量均显著高于对照组（p〈0．05）,且稚鲍成活率亦有显著性提高。试验结束时大蒜素组的成活率最高,可达60．00±3．33％;其次为益母草膏、腐殖酸和维生素B6组,成活率分别为56．60±1．66％、45．05±2．44％和42．67±3．13％;均极显著高于对照组的8．59±7．14％（0〈0．01）。由此可见,增强机体的抗氧化能力可提高稚鲍的成活率;本试验所选用的4种免疫因子均可提高九孔稚鲍的免疫力．能有效地提高鲍鱼的附板率。     

九孔鲍人工育苗技术探讨

采用阴干加紫外线处理海水催产的方法，进行九孔鲍室内人工育苗研究，使用雌亲鲍1343粒，平均规格5．7cm，雄亲鲍117粒，平均规格5．8cm，共获得受精卵9500万粒，受精率91．5％，以塑料薄膜作为附着基质，共附着匍匐幼体607万粒。经过64～73d的附着期间的管理，剥离0．21～1．0cm稚鲍347万粒，成活率达57．2％，又经过98～102d的培育，获得规格1．0～2．5cm的鲍苗121．5万粒，平均成活率达35．0％。     

杂色鲍自然海区人工放养的初步试验

本文报道了杂色鲍标志放养和人工造礁试验的方法和结果．试验表明，杂色鲍的最适放养壳长为2．5—3．0厘米；2龄的杂色鲍，平均壳长为4．8厘米，这一龄段的鲍生长最快，3龄的杂色鲍平均壳长为6．3厘米，最大的个体可达7．0厘米；4龄以后，其生长明显减慢。据此，似可将3—4龄，壳长超过6．0厘米的杂色鲍定为上市规格。此外，本文还对杂色鲍对自然环境的适应、生长、移动，以及人工造礁的方法和效果作了介绍。     

皱纹盘鲍工厂化育苗技术

利用坑道培育和海捕的皱纹盘鲍亲体，进行人工催产、授精；以高密度集中培育浮游幼虫；用以舟形藻、卵形藻和菱形藻为主的底栖硅藻作为开口饵料，进行稚鲍前期培育；以幼鲍专用饲料作稚鲍后期饵料，进行稚鲍后期流水平面培育。1996年在8m2的采苗水面培育出壳长1．0～1．2cm的稚鲍2．4万个；1997年在50m2的采苗水面培育出壳长1．0～1．7cm的幼鲍16万个。     

长吻旎网箱养殖试验

2005年网箱培育长吻能冬片鱼种，应用5m×5m×3．5m的网箱，放养规格为3～4cm／尾的长吻鲍夏花鱼种，放养密度56～790尾／m^2，投喂粗蛋白为42％～46％的配合饲料，经7个月养殖，长吻鲍鱼种平均规格达165g／尾，成活率82．5％，单产9kg／m^2，饲料系数1．26，投入产出比1：2．04；2006年网箱养殖长吻脆商品鱼，应用5m×5m×4．5m的网箱，放养规格为133g／尾左右的长吻能冬片鱼种，放养密度32～50尾／m^2，投喂粗蛋白为42％～43％的配合饲料，经6个半月时间的养殖期，养成个体规格在0．5kg／尾以上的长吻娩商品鱼比例达86％以上，成活率82．6％～87．0％，饲料系数1．38，单产22．83～26．24kg／m^2，投入产出比1：1．59。     

皱纹盘鲍4个群体与九孔鲍16S rRN A基因遗传差异分析

采用PCR方法扩增了皱纹盘鲍（4个群体）和九孔鲍（1个群体）共5个群体（53个样本）16S rRNA基因片段（16S）,测序获得了1000 bp核苷酸序列,其中669 bp核苷酸序列用于遗传差异分析,旨在评估我国皱纹盘鲍不同群体间及其与九孔鲍间的遗传差异。从52个序列中共检测到17种单倍型,其中皱纹盘鲍4个群体有13种单倍型,九孔鲍1个群体（9个样本）有4种单倍型。单倍型核苷酸序列比对显示,变异位点占比对位点的20．5％,基于单倍型的皱纹盘鲍4个群体间的遗传距离为0．002～0．011,平均为0．005;九孔鲍群体内的平均遗传距离为0．004,两种鲍间的平均遗传距离为0．218;两种鲍间的遗传分化系数 F‐统计量 FST平均为0．982,皱纹盘鲍4群体间的 FST值为0．0051～0．0065。本研究显示2种鲍群体内16S变异很小。系统发育分析鲍属11种鲍的聚类关系,显示皱纹盘鲍与盘鲍、日本鲍交叉聚为一支,九孔鲍与杂色鲍也交叉聚为一支,4个种类未聚成单系支。     

“食神”对仔猪生长性能的影响

选35～45日龄仔猪90头，随机分成试验一组（每吨配合饲料添加“食神”1．6kg，舍半胱胺80g／t）、试验二组（每吨配合饲料添加“食神”2kg，含半胱胺100g／t）和对照组（不添加任何添加剂），每组30头，做对比试验。其结果明显：试验组较对照组日增重提高7．5％～9．0％，料内比下降3．6％～4．7％，发病淘汰率降低41．7％～43．6％，平均每头猪的毛利提高了13.3％～14．8％。可见日粮中添加食神，能有效的提高生产指标和抗病能力，且有明显的经济效益。     

皱纹盘鲍与盘鲍杂交技术的研究

采用皱纹盘鲍大连群体与盘鲍日本群体进行杂交育苗试验和鲍苗种生产。结果表明,皱纹盘鲍和盘鲍正、反交组合的受精率和孵化率均低于两亲本自交组,而其苗种成活率高于两亲本自交组（提高达20％以上）;皱纹盘鲍和盘鲍的正、反交组合鲍苗的生长情况是,其平均壳长明显高于两亲本自交组鲍苗的平均壳长,最长达2．01 cm ;皱纹盘鲍与盘鲍作为亲本进行鲍苗种生产,经160 d培育,共培育出鲍苗种2020．75万只（平均壳长2．01 cm ）,鲍出苗量平均4345．7只／m2。通过鲍种内杂交的育种方法,可以达到改良和优化鲍种质的目的。     

潮间带垒石蒙网养鲍技术研究

1994年4月～1995年10月，在4个岩礁区共设置136个石垛，放养壳长1．3～3．0cm鲍苗55．1万只，进行潮间带垒石蒙网养鲍试验。对场址选择、放养密度、规格、投饵方法等进行了研究。结果：产商品鲍19．254t，平均亩产1397．8kg，平均壳长6．81cm，平均个体重39g，成活率89．6％，实现产值693.144万元、利润352.81万元。专家鉴定认为，养殖方式为国内首创，技术水平属世界先进。     

中国沿岸几种鲍线粒体16S rRNA基因片段序列比较及鲍属系统发育

用PCR技术克隆耳鲍（Haliolis asinina）、羊鲍（H．ovina）和多变鲍（H．varia）的线粒体16S rRNA基因的片段，并将PCR产物直接进行测序，得到长度530bp左右的片段。将这些序列与杂色鲍（H．diversicolor diversicolor）、九孔鲍（H．diversicolor supertexte）、大鲍（H．gigantea）、盘鲍（H．discus discus）、皱纹盘鲍（Haliotis discus hannai）等5种鲍的相应片段进行序列比较。结果表明，不同种鲍间16S rRNA基因的序列同源性较高，同源性范围为87．36％～90．77％，这说明鲍的这段基因片段在遗传过程中比较保守。序列的A＋T含量约为56．68％，G＋C含量约为43．32％。8种鲍序列的主要核苷酸变异位点集中在1-25bp、240-290bp和320～370bp3个区域。在序列的变异碱基巾，碱基的转换大大多于碱基的颠换，转换与颠换之比达到2．33：1，遗传距离的范围为0．002-0．128。用UPGMA法和NJ法绘制出8种鲍的系统发育树。结论认为，大鲍、皱纹盘鲍和盘鲍之间的遗传差异水平为亚种间的差异水平，台湾产的九孔鲍与大陆沿岸产的杂色鲍之间的差异仅仅是种群间的差异。     

不同投饵率对暗纹东方鲀幼鱼生长的影响

比较投饵率水平分别为3%、4%、5%、6%时,对暗纹东方鲀幼鱼生长、饲料效率的影响,以确定暗纹东方鲀幼鱼阶段的适宜投饵率。在23℃下,对规格为3.45～3.56g的暗纹东方鲀幼鱼进行30d的生长实验,结果表明:不同投饵率对暗纹东方鲀幼鱼的特定生长率、质量相对增加率、饲料效率、存活率均有显著影响(p<0.05);暗纹东方鲀幼鱼的适宜投饵率为4%,在投饵率为4℅时,质量相对增加率为116.04±0.04%,饲料效率达83.70±0.02%,特定生长率为111.49±0.03%/d,存活率为84.44±0.02%。     

生物絮团对水质的调控作用及仿刺参(Apostichopus japonicus)幼参生长的影响

采用模拟实验与现场实验相结合的方法,通过添加3种微生态制剂及碳水化合物作为碳源,研究了其在生物絮团形成与水质调节中的作用,并分析了其对水中无机氮含量、悬浮物、细菌总数及幼参生长的影响,为阐明生物絮团在刺参工厂化苗种培育中的生态环境调控作用提供依据。结果表明,亚硝态氮易于在培育池水体中累积,可高达0.25 mg/L;添加芽孢杆菌后,水中总悬浮物含量和细菌总数均为最高值,且未检测到弧菌和大肠菌群;第20天,仅添加蔗糖组幼参增重与特定生长率均明显高于其他复合碳源组和对照组(P0.05),分别为44.34 g和2.19%/d;而添加蔗糖和芽孢杆菌组增重与特定生长率均明显高于其他处理组和对照组(P0.05),分别为66.60 g和3.01%/d;复合碳源组幼参增重与特定生长率随着玉米淀粉含量增加而逐渐降低,但与对照差异均不显著(P0.05)。结果显示,以蔗糖为碳源,添加芽孢杆菌形成的生物絮团不仅可以改善水体水质和微生态结构,还可以明显促进幼参的生长。     

Effects of water flow rate on growth rate,mortality and biomass return of abalone in slab tanks

The capital‐intensive nature of land‐based abalone farming demands that infrastructure be fully utilized. This study investigated whether the negative impact of high stocking density in shallow raceway tanks could be ameliorated by optimizing water flow. We quantified the effect of flow rate (87–246 L min^?1) on the performance of 2‐year‐old hybrid abalone (Haliotis laevigata and Haliotis rubra) held at two stocking densities (11400 and 7600 tank^?1). A 50% higher density yielded a 27% increase in biomass gain, despite a 10% growth reduction and 3% higher mortality. At the lower density, there was an optimal flow rate of approximately 200 L^?1, at which biomass gain was 474 kg and the feed conversion ratio (FCR) was 1.31. At the higher density, biomass gain (max = 658 kg) and FCR (min = 1.41) improved linearly with increasing flow, suggesting that an optimal flow rate exists at 246 L^?1 or beyond those tested. Increased oxygen availability with increasing flow is thought to have enhanced abalone performance, although flows greater than 200 L min^?1 may have reduced performance at low density due to feed washout and nutrient leaching. Overall, greater financial return per tank was favoured by the combination of high stocking density and high water flow.     

The Effects of Water Exchange on Production of Metapenaeus macleayi and Water Quality in Experimental Pools

Two experiments in 4 m diameter, plastic lined pools were conducted nt two densities, 20 shrimp/ m² and 47 shrimp/m², to determine the effects of water exchange rate on the production of the penaeid shrimp Metapenaeus macleayi (Haswell) and on water quality variables. Water exchange rates ranged from 0–40%/d for the 9 wk low density experiment and 0–20%/d for the 8 wk high density experiment. With the exception of mass mortality after prawns escaped from one pool (0% water exchange) on the last day of the high density experiment, shrimp performance indices (survival, weight gain, biomass gain and food conversion ratio) were not significantly affected by water exchange rate. During both experiments water exchange significantly reduced the concentrations of phosphorus and plant pigments (chlorophyll a, b and c and pheophytin) but had no significant effect on pH or the concentration of ammonia or nitrite plus nitrate. Data from this study suggest that while production ponds should not be managed for extended periods without water exchange, simply increasing daily water exchange rates may not necessarily increase shrimp growth or survival. Water exchange can reduce nutrient concentrations and phytoplankton densities but most of the reduction occurs at water exchange rates of between 0–5%/d.     

Some effects of feeding rate on growth,feed conversion and nutrient absorption of channel catfish

In an 8-week trial, 300-g channel catfish (Ictalurus punctatus) were fed at five feeding rates: a control group which was fed at a rate that approximated the ad libitum rate for this size fish, and four groups which were fed at 110, 90, 75 and 50% of the control rate. Significant decreases in growth and feed conversion (feed/gain) rates were obtained in treatments fed 110% of the control rate. Water quality monitoring indicated that this reduction in performance was not due to poorer water quality. Gains were not significantly affected by feeding 90% of the control level, but were reduced in the 75 and 50% treatments. Food efficiencies were improved by reduction of the feeding rate to 90 and 75% of the control level, but were not further improved at the 50% feeding level. Total absorbability and digestible energy values for the test diet were improved by restricting the rate to 90% of the control, but protein absorbability was not affected.     

低聚果糖对仿刺参生长及生长免疫因子的影响

在基础饲料中分别添加0(对照组)、0.20%、0.40%、0.60%、0.80%、1.00%的低聚果糖,制作6组等氮、等能的试验饲料,投喂初始体质量约20 g的仿刺参14周,研究低聚果糖对仿刺参生长、体成分、机体生长免疫因子及肠道糖代谢酶活力的影响。试验结果表明,低聚果糖添加量对仿刺参的成活率无显著影响(P>0.05),但显著影响了仿刺参的质量增加率和特定生长率(P<0.05);仿刺参体壁基本成分不受低聚果糖添加量的影响(P>0.05),总糖含量随低聚果糖的升高而升高(P<0.05);体壁中甘氨酸、半胱氨酸及精氨酸含量随低聚果糖含量的增加呈先升后降的趋势,分别在0.40%、0.50%、0.80%组达到最高,显著高于0%组(P<0.05);体腔液中生长激素、补体C3、补体C4及一氧化氮合酶含量均随低聚果糖的升高呈先升后降的趋势,但肠道丙酮酸激酶和己糖激酶活力均随低聚果糖的升高而升高(P<0.05)。以质量增加率为评价指标,经二次曲线回归分析,仿刺参饲料中低聚果糖的适宜添加量为0.55%。     

Temporal Growth Patterns of Farmed Juvenile Southern Bluefin Tuna, Thunnus maccoyii (Castelnau) Fed Moist Pellets

The growth, condition, and feed utilization patterns of juvenile southern bluefin tuna (SBT) fed moist‐pellets were examined over a 19‐wk period from March to July 1999. The SBT had significant weight gain over the course of the study, increasing on average from about 27 to 34 kg (dependent on size class). No significant weight gain by the SBT occurred in the first 5 wk of the study. Following this initial period of slow growth, the rate of weight gain increased, ranging between 40 to 90 g/d. Weight gain peaked after 11 wk, with no further gain occurring after this time point. Weight gain was strongly related to average daily feed intake (AFI) which was predominantly influenced by water temperature. Weight gain was minimal following the decrease of water temperatures below 15 C, consistent with a decrease in feed intake from peak values at the beginning of the study to basal levels by week 13. Basal feeding levels were maintained for the remainder of the study through to week 19. Although water temperature and AFI were strongly related, other time related effects also appeared to be signillcant. A relationship between condition index and feed intake was also identified. Condition index of the SBT increased from about 19 kg/m³ to 22 kg/m³ over the 19‐wk period. Similar to the patterns observed in growth, there was also an initial delay in increases of condition index. The results from this study support that the majority of weight gain by juvenile SBT occurs during the early part of the production season and that this is most likely influenced indirectly through responses to water temperature. The results of this study also suggest that there is little value in conducting growth trials beyond the point where water temperatures decrease below 15 C. Although there was minimal weight gain or improvement in condition beyond the 11‐wk time point, these parameters would need to be considered in conjunction with flesh quality characteristics to identify optimum harvesting regimes.     

Effects of pond preparation and feeding rate on production of Penaeus monodon Fabricius, water quality, bacteria and benthos in model farming ponds

Fibreglass pools with sediment were used as model farming ponds to investigate the interactive effects of pond preparation and feeding rate on prawn production, water quality, bacterial dynamics, abundance of benthos and prawn feeding behaviour. Pools were either fertilised 1 month (prepared) or 2 days (unprepared) prior to stocking and either ‘high’ or ‘low’ feeding rates were used. The ‘high’ rate was 5.0% (range 4–8%) wet prawn biomass/day and was similar to that recommended for commercial farms. The ‘low’ rate was 2.5% (range 2–4%) wet prawn biomass/day. Juvenile Penaeus monodon (2.0–7.5 g) were stocked at 15 prawns/m² and were cultured for 71 days. With the exception of one prepared, high feeding-rate pool where mass mortality (> 80%) of prawns occurred following an interruption to aeration, prawn survival was high (> 86%) and was unaffected by preparation, feeding rate or their interaction. Pond preparation improved growth and biomass gain by about 20%. Growth was 4% higher with the higher feeding rate but biomass gain was not affected and, as food conversion ratio was much worse, use of the lower feeding rate offers considerable scope to reduce production costs, especially during cooler periods. There was no interaction in relation to growth between pond preparation and feeding rate. Meiofauna were more abundant, and prawns grew faster, in prepared pools than unprepared pools at the start of the experiment. However, changes in bacterial dynamics or meiofauna abundance over time did not explain reductions in prawn growth over time. In general, water quality was reduced in pools receiving the high feeding rate compared with low feeding rate pools. Other interactive effects of pond preparation and feeding rate on water quality, bacteria, benthos and prawn feeding behaviour are discussed.     

Effects of Bdellovibrio and Like Organisms on Survival and Growth Performance of Juvenile Turbot,Scophthalmus maximus

In this study, the impact of Bdellovibrio and like organisms (BALOs) on juvenile turbot rearing was investigated in a static water rearing system with weekly partial change of water. A 60‐d‐long rearing experiment showed that, compared with control, survival rate, percent weight gain, percent length gain, and average daily growth were 92 ± 2.8%, 387.1 ± 4.6%, 78.6 ± 1.5%, and 1.87 ± 0.79 g/d, respectively, significantly higher than those in the control, viz., 81 ± 3.2%, 248.2 ± 5.3%, 56.7 ± 2.1%, and 1.16 ± 0.68 g/d, respectively. Water quality results demonstrated that no significant difference (P > 0.05) was observed between test and control with the addition of BDW03. Compared with the control, total culturable bacteria and total vibrio numbers in rearing water and in intestines were significantly (P < 0.05) reduced by 0.8–1.4 log CFU/mL/ log CFU/g, with the addition of BDW03. Furthermore, denaturing gradient gel electrophoresis profiles in rearing waters collected at a 1.5‐d interval over a week revealed that BDW03 simplified bacterial community structures with time, and some vibrios disappeared with the addition of BDW03. To the best of our knowledge, this is the first report that BALOs can promote growth and survival of juvenile turbots and be beneficial to coldwater fish aquaculture at the production level.     

枯草芽孢杆菌改善水质提高凡纳滨对虾幼体抗逆性的研究

投放不同浓度梯度的枯草芽孢杆菌于凡纳滨对虾幼体养殖环境中,监测不同枯草芽孢杆菌使用浓度下与养殖环境相关的水质因子（氨氮、亚硝酸盐氮、化学需氧量）的变化;观察不同枯草芽孢杆菌使用浓度下凡纳滨对虾幼体对人工制造的胁迫环境的抗逆性;观测不同枯草芽孢杆菌使用浓度下凡纳滨对虾幼体的成活率与体重增长率。研究枯草芽孢杆菌对水质改善和凡纳滨对虾幼体抗逆性的影响。结果表明,枯草芽孢杆菌能显著（P〈0.05）降低化学需氧量、氨氮含量,抑制亚硝酸盐氮的产生;当枯草芽孢杆菌投放浓度为1.25×10^4cfu/ml时,水体中化学需氧量、氨态氮、亚硝酸盐氮含量均值比对照组分别降低了65.30%、59.70%、88.64%,成活率比对照组提高了10.00%,体重增长率是对照组的2.44倍;当枯草芽孢杆菌使用浓度为1.25×10^4～1.25×10^6cfu/ml时,对虾抗逆性显著（P〈0.05）增强,对虾在氨氮、亚硝酸盐氮、高锰酸钾、甲醛胁迫下24小时的成活率均值分别比对照组提高了16.94%、24.44%、44.17%、18.61%。