光合成细菌在斑节对虾育苗中的应用初步研究

<正> 光合成细菌(Photo Synthetioc Ba-cteria),是一类分布于江河、湖泊、海洋中,可在人工培养条件下迅速繁殖的微生物,由于其具有较强的利用水体中低级有机物的特性,其菌体富含蛋白质、维生素,生物素等动植物所不可缺少的营养成份的优点,因此是净化水质和作为饲料添加剂的理想材料。为了探索光合成细菌在斑节对虾育     

斑节对虾养殖池塘藻-菌关系初探

本研究通过对斑节对虾养殖系统中的异养细菌、浮游微藻进行为期3个月的监测，发现浮游微藻和异养细菌的总量都表现为养殖后期高于养殖前期，其中浮游微藻增加了2个数量级，异养细菌增加了1个数量级，施放有益芽孢杆菌群对池塘菌群和藻群的变动有明显的影响。施放有益芽孢杆菌群的池塘，异养细菌总数略低，弧菌数量维持在10^3 CFU／mL以下，浮游微藻平稳增长，蓝藻占20％以下；对照池异养细菌的总数略高，弧菌数量达到10^3 CFU／mL，浮游微藻数量波动，养殖后期蓝藻占60％，为绝对优势种群。表明有益芽孢杆菌群有促进浮游微藻平稳繁殖的作用，但对浮游蓝藻和弧菌的繁殖起抑制作用，浮游蓝藻与弧菌之间具有一定的繁殖相关性。     

斑节对虾室外人工育苗试验报告

<正> 斑节对虾(Penaeus monodon)又称角虾、青根虾,台湾称草虾,它个体大,生长速度快,且对饵料选择不严格(偏植物性),广盐性,耐高温,离水后的抵抗耐力强,具有活虾出口的优越条件,是虾类养殖的理想品种,是东南亚各国及我国南方、台湾省对虾养殖的主要品种。近几年来,斑节对虾工厂化育苗取得了可喜的成绩,产量逐年增     

残饵及代谢物对斑节对虾育苗的影响

试验对象为平均体重0.57毫克、全长6.5毫米的斑节对虾后期幼体,放养在充气的海水水族箱内,密度为每升20尾,试验用的饲料为碎虾肉,各试验组的投饲量分别为10毫克/升、50毫克/升、100毫克、250毫克/升和500毫克/升,并设一水族箱投喂硅藻作对照。试验结果表明:投饲量为10毫克/升、50毫克/升、100毫克/的试验组,后期幼体的增重率接近,且都比对照组高一倍左右;最低投饲量试验组的成活率较好,与对照组比较无显著差异(P>0.05);其它试验组的成活率随投饲量增加而下降;投饲量为50毫克/升时,仔虾的成活及生长均可,超出这个投饲量,水体中有机物和代谢物积累加快,溶氧量下降,水质迅速恶化。     

台湾省的斑节对虾育苗技术

斑节对虾Penaeus monodon是目前台湾省虾类养殖的主要对象。自1968年以来,斑节对虾的养殖产量逐年递增,其速度之快相当惊人。1968～1977年,其成虾年产量由61吨上升到1,000吨,增长约16倍;至1985年,成虾年产量达到30,000吨,较1977年又增长近30倍。最近三年间,产量继续上     

斑节对虾人工育苗技术

斑节对虾俗称“草虾”,是虾农所喜爱的虾类之一。草虾人工育苗是一项既具高难度技术,又具高利润的工作。再者这几年,海区水质受到不同程度的污染,草虾育苗工作风险更大。现将育苗主要技术介绍如下。     

弧菌影响斑节对虾受精卵和无节幼体发育的研究

用8种弧菌对斑节对虾受精卵和无节幼体进行感染试验,结果表明,8种弧菌严重地影响虾卵的孵化和幼体的正常发育,其中以混合弧菌感染致病性最强。试验还显示了弧菌对越是早期的胚胎侵害力越强。     

斑节对虾健康育苗的技术措施

<正> 斑节对虾(Penaeus monodon),是暖水性对虾类,具有对环境适应力强、生长快、个体大、经济价值高等优点,早在80年代初已成为东南亚各国及我国南方沿海地区对虾养殖的主要品种 近年来,随着海南省对虾养殖面积的不断扩大和放养密度的增加,虾病蔓延之势日趋严重,养殖风险越来越大,成为制约当地对虾养殖业发展的主要因素。1998年3～5月,海南省对虾养殖暴发性病害相当严重,在对虾养殖面积较集中的万宁市,虾池发病率高达80％,除了与沿海水域的污染、气候条件     

试论斑节对虾人工育苗中的几个问题

斑节对虾(俗称草虾)人工育苗在广东已进入集约化、工厂化大规模生产阶段,为对虾养殖业的稳步发展奠定了良好的苗种基础。现从亲虾的选择和催熟、育苗水质、加温和充气、饵料、病害防治等几个技术环节进行探讨,以祈抛砖引玉达到虾苗质优价廉,使斑节对虾养殖更快地发展。     

斑节对虾室内育苗与室外育苗的比较

采用室外水泥池遮光与传统的室内水泥池育苗两种方法进行斑节对虾的种苗培育，并比较其育苗效果。结果显示；早春季节，室外育苗与室内育苗相比，成活活率提高17.0%，育苗周期缩短4-7天，且虾苗质量好，均匀度高；而秋季育苗，两种方法育苗的成活率差别不明显，室外育苗风险增大，但与室内育苗相比可缩短育苗周期3-5天，且虾苗的质量好，均匀度高。     

军曹鱼肠道及水体异养菌和弧菌的周年变化

采用总活异养菌2216E平板计数法和弧菌TCBS平板计数法对广东深圳大鹏养殖军曹鱼(Rachycentron canadum Linnaeus)养殖水体及鱼肠道细菌进行了周年监测。结果显示,育苗初期养殖水体异养菌和弧菌密度分别为0.63×104～6.2×104CFU/mL和0.30×102～1.03×104CFU/mL,鱼肠道异养菌和弧菌密度分别为0.80×106～7.5×107CFU/g和0～1.30×107CFU/g;网箱养殖监测期间,养殖水体异养菌和弧菌密度分别为4.20×103～5.40×105CFU/mL和0.70×102～1.14×105CFU/mL,鱼肠道异养菌和弧菌密度分别为1.50×107～8.78×108CFU/g和1.00×107～3.50×108CFU/g。周年监测结果显示,水体异养菌、弧菌的数量高峰均出现于8-9月份;肠道异养菌及弧菌的数量高峰均出现于6-7月份,分别又在12月份和2月份出现次高峰,弧菌变化趋势始终与异养菌一致。对分离得到的407株菌鉴定到属并进行多样性分析。结果显示,育苗期水体以假单胞菌(Pseudomonas)、黄单胞菌(Xanthomonas)和芽孢杆菌(Bacillus)为优势菌,三者约占水体异养菌总数的70%;养殖后期,弧菌(Vibrio)和发光杆菌(Photobacterium)的数量逐渐上升并占据一定优势,其中假单胞菌、黄单胞菌、弧菌和芽孢杆菌常年出现。鱼肠道异养菌以假单胞菌和芽孢杆菌为优势菌,其次是肠杆菌科(Enterbacteriaceae)细菌,也多次检测到弧菌、发光杆菌、气单胞菌(Aeromonas)和小球菌(Microccus)等。总之,养殖微生态系统的可持续稳定平衡与系统的种群多样性、群落组成及水质因子等因素相关,而整个环境生态系统的平衡直接影响到鱼类肠道的细菌生态系统。     

Formulated Feeds Containing Fresh or Dried Artemia as Food Supplement for Larval Rearing of Black Tiger Shrimp,Penaeus monodon

Supplementation of microalgae and Artemia nauplii with practical formulated feeds containing fresh or dried Artemia biomass for larval rearing of black tiger shrimp, Penaeus monodon, was assessed. Five feeding treatments were carried out in a recirculating seawater system with fifteen 30-L fiberglass tanks. Shrimp nauplii were stocked at a density of 150 L^?1 for 23 days. In the control treatment, live feed was supplemented with commercial formulated feed (Inve Aquaculture NV, Belgium). In two other treatments, live feed was supplemented with a pelleted feed based on either fresh or dried Artemia. In the remaining two treatments live feed was supplemented with a combination of 50% commercial feed and 50% fresh or dried Artemia feeds. Overall, performance of PL in the combination treatments (commercial feed and Artemia diets) were equal to or better than those fed commercial feed alone as seen by the better growth rate and higher resistance to formalin stress. The results indicate that feed containing fresh or dried Artemia biomass can partially supplement live feeds for larval rearing of P. monodon.     

斑节对虾池塘淡化养殖试验

投放平均体长0.8cm的斑节对虾苗种，经120d养殖，平均体长11.6cm，平均产量为1808－2860kg/hm^2，出池规格19.2g，成活率40％－56％，投入产出比1：1．55－2．10，为生产单位推广养殖提供可行的技术措施。     

斑节对虾基因组微卫星分离及其序列特征研究

采用(CA)_(12)(AG)_(12)及(TA)_(16)生物素标记探针及磁珠富集法构建了斑节对虾Penaeus monodon基因组微卫星富集文库。随机挑选254个克隆进行PCR筛选,得到51个候选克隆(20．1%)。其中,32个克隆来源于CA-文库,另19个克隆来源于AG-文库。测序发现48个克隆含有微卫星重复单元,通过序列比对,最终获得40个具有特异微卫星序列的阳性克隆。微卫星(GA/CT)_N及(CA/GT)_n 2碱基重复序列分别占所有分离的微卫星数目的20．7%及60．4%。此外,还检测到其它多种微卫星重复类型,如(AT)_n、(GC)_n、(TGG)_n、(AAG)_n、(AAT)_n、(GAA)_n、(GTGC)_n、(GCGT)_n、(GGTTA)_n、(GTGCGT)_n,占检测到的微卫星数目的18．9%。获得的微卫星序列中属于完全型序列的有76条(68．5%),不完全型序列的有22条(19．8%),另有13条属于复合型序列(11．7%)。微卫星(GT/CA)_n 2碱基重复次数(3～52次)要远大于(GA/CT)_n 2碱基次数(3～27次)。获得的微卫星序列长度大小范围为129～601 bp,平均为286 bp。研究为进一步开展斑节对虾分子育种及资源评价分析提供了基础资料。     

斑节对虾与凡纳对虾幼体对卤虫无节幼体摄食量的比较试验

用1000ml小水体进行斑节对虾和凡纳对虾各期幼体对卤虫无节幼体摄食量的比较实验，结果表明，二种对虾的卤虫摄食量与卤虫密度有关，在相同密度下，糠虾期凡纳对虾卤虫日摄食量明显高于斑节对虾，而卤虫密度对摄食量的影响凡纳对虾略低于斑节对虾，仔虾期卤虫摄食量差异日渐减小，P5-P6已很接近。     

Probiotic bacteria effects on growth and bacterial composition of black tiger shrimp (Penaeus monodon)

The effects of Bacillus probiotic forms on growth performance and microbiota were examined in black tiger shrimp (Penaeus monodon). Shrimp were fed for 120 days with one of three diets; a control diet alone or supplemented with either probiotics consisting of live‐sprayed Bacillus (LS) or freeze‐dried Bacillus (FD). Culturable bacteria counts in the hepatopancreas, intestine and culture water of the three treatments were relatively constant during the experiment. Bacillus numbers in the hepatopancreas and intestines of probiotic‐treated groups increased significantly (P < 0.05) after 30 treatment days and remained relatively constant afterwards while no appreciable changes occurred in the control. Shrimp supplemented with LS and FD contained significantly lower concentrations of Vibrio (P < 0.05) in the hepatopancreas, intestine and culture water, compared to those in the control group. Shrimp treated with LS and FD probiotic bacteria showed a significant improvement (P < 0.05) in specific growth rate (SGR) and feed efficiency (FE), compared to those of control group. Probiotic bacteria have the potential to enhance shrimp culture by reducing Vibrio and improving growth performance.     

The effectiveness of a commercial microbial product in poorly prepared tiger shrimp, Penaeus monodon (Fabricius), ponds

The efficacy of a commercial microbial product was tested in commercial tiger shrimp, Penaeus monodon (Fabricius), ponds for one culture period in Kuala Selangor, Malaysia. Four ponds with replicates for treatment and control were used. The pond bottom was dried but the organic sludge was not removed as normally practised in pond preparation. The ponds were stocked with 15 post‐larvae at the rate of 31.m^?2. Physical, chemical and biological parameters of the pond were analysed every 2 weeks during the culture period. Water quality parameters remained within the optimum range for shrimp culture except for ammonia‐nitrogen being significantly higher in control ponds and silica in treated ponds. Benthic organisms were not found in any of the ponds. The average counts of different bacteria were not significantly higher in treated ponds than control. Because of poor health, the shrimp were harvested earlier (72 days) than the usual 120 days. An average of 875.60 ± 67.00 kg shrimp ha^?1 was obtained in treated ponds with a feed conversion ratio (FCR) of 1.57 ± 0.10 and survival rate of 42.35 ± 5.37% compared with 719.50 ± 130.94 kg shrimp ha^?1, 2.99 ± 0.70 and 21.25 ± 3.26%, respectively, in control ponds. Neither the microbial product nor the frequent water exchange was effective in overcoming the problems caused by the poor pond bottom.     

池塘养殖斑节对虾生长、发育与性成熟

为了解不同养殖条件下斑节对虾的生长、外生殖器发育、性腺发育及性成熟之间的关系,对其养殖进行跟踪调查研究.结果显示:①斑节对虾雌雄外生殖器官发育和头胸甲长呈线性关系;②不同养殖环境条件下,斑节对虾性成熟生物学最小型个体无显著差异.雄性精荚出现的生物学最小型个体为头胸甲长3.1 cm,体长11.1 cm,体质量20.0 g;雄性性成熟个体的头胸甲长3.7 cm,体长13.0 cm,体质量37.0 g.池养雌性斑节对虾的性成熟生物学最小型个体以纳精囊的发育完全(可与雄虾交配)为标志,其最小性成熟个体的头胸甲长4.3 cm、体长15.1 cm、体质量53.0 g,雌性性成熟个体为头胸甲长5.0 cm,体长17.0 cm,体质量75.0 g以上;③池塘养殖斑节对虾性成熟与日龄和养殖环境相关.鱼塭雄虾精荚出现的最早时间为日龄120 d前后,其性成熟日龄约为160 d;池塘养殖雄虾精荚出现的最早时间为日龄150 d前后,其性成熟日龄约为260 d.鱼媪雌虾最早交配发生在日龄165 d前后,性成熟日龄205～236 d,池养雌虾最早交配发生在日龄240～ 280 d,性成熟日龄295～360 d以上.     

宽沟对虾人工育苗试验

此次人工育苗试验 ,共投放无节幼体 1.1× 10 6尾 ,培育成仔虾 (P6) 7.8× 10 5尾 ,育苗成活率为 6 2 .4 % ,此外还观察了胚胎发育和幼体发育