光合细菌的鉴定、生长特性及其应用

光合细菌HZPSB株分离自淡水养殖池塘底泥,经富集与纯化培养,菌落形态、培养特征和菌体形态学观察,细胞吸收光谱及生理生化特性测定,鉴定为类球红细菌(Rhodobacter sphaeroides).测定了HZPSB株的最佳培养条件,其最佳培养条件为29℃、3000Lux、pH7.0和1‰盐度.测定了光合细菌对池塘水质(溶氧、pH、氨氮、亚硝酸盐氮、COD)影响;添加于饲料后对鱼血清中溶菌酶活力的影响;同时进行了光合细菌的大田应用试验.结果表明:光合细菌对池塘水的溶解氧、pH没有影响;降低水中氨氮、亚硝态氮、有机物(COD);饲料中添加光合细菌饲喂鲫鱼、罗非鱼,鱼血清中溶菌酶的活性明显高于对照组.光合细菌分别在湖州、绍兴、杭州、嘉兴、上海等进行大田应用试验,取得了较好的应用效果.养殖虾蟹的发病率有明显的减少,与不使用光合菌的池塘相比,发病率降低了25%以上,提高了虾蟹产量.     

罗非鱼池塘投放光合细菌后水质研究

本文利用光合细菌改善池塘水质的作用,测定了池塘水质(溶氧、NH 4-N、NO-2-N、COD)、透明度、pH及异养细菌总数,研究水质和浮游生物的变化情况.实验结果表明:投放光合细菌后,对降低水中COD、氨氮、透明度,提高亚硝酸态氮等有一定的效果;但是对水中溶氧、pH值、硝酸态氮等的变化并没有起太大的作用.     

一株光合细菌的分离筛选及其对无机氮的去除能力

通过对海洋环境污泥进行富集培养及分离筛选得到一株光合细菌,通过16S rDNA全序列分析,结合菌株形态和结构,鉴定其为Ectothiorhodospira magna。研究表明菌株在盐度30‰、28℃、DO 8 mg/L的条件下,对初始浓度分别为280、84、98 mg/L的氨氮、亚硝酸盐氮和硝酸盐氮经过10 d处理的去除率分别为81.83%、46.21%、86.79%。在氨氮、亚硝酸盐氮和硝酸盐氮共存的环境下,菌株首先利用氨氮,之后将亚硝酸盐氮转化成硝酸盐氮。     

包膜硫酸钠/过氧化氢/氯化钠加合物对尼罗罗非鱼养殖水体的改善效果

选取经食盐水浸浴10 d后平均体重为40 g左右的健康尼罗罗非鱼,随机分成两组,一组为对照组.另一组为试验组,每组设3个重复,每个重复30尾,饲养于水族箱中.试验组按3 g/m3水的添加量投放包膜硫酸钠/过氧化氢/氯化钠加合物,每2 d投放1次,试验期20 d,试验期间不换水,24 h增氧,每天两次投饵,不捞残饵,研究包膜硫酸钠/过氧化氢/氯化钠加合物对尼罗罗非鱼养殖水体的改善效果.结果表明,(1)试验组和对照组水体的溶氧和pH值没有明显的差异;试验组和对照组氨氮、亚硝酸盐氮和COD浓度均随着试验时间的延长而升高,相同时间点试验组水体氨氮、亚硝酸盐氮和COD浓度均低于对照组,其中氨氮在第12、15和20天达到显著水平(P＜0.05),亚硝酸盐氮和COD在第9、12、15和20天达到显著水平(P＜0.05);(2)与对照组相比,试验组养殖水体细菌数量显著降低(P＜0.05);(3)与对照组相比,试验组尼罗罗非鱼日增重、特定生长率和存活率分别提高40%(P＜0.05)、40.9%(P＜0.05)和14.2%(P＜0.05),饵料系数降低12.3%(P＜0.05).     

高效复合微生态制剂对养殖水体修复效应的研究

利用模拟池塘水质实验和采集水处理实验来验证高效复合微生态制剂(枯草芽孢杆菌:球形赖氨酸芽孢杆菌:蜡状芽孢杆菌为2∶1∶1)的脱氮效果。模拟实验中,亚硝酸盐的去除率达75%,氨氮的去除率在40%;采集水实验中,氨氮和亚硝酸盐的去除率分别为34%、48%,除此之外,COD的去除率可达30%。     

水芹对富营养化水体的净化效果研究

利用聚乙烯板作为浮床栽植水芹(Oenanthe javanica),观测其对4组不同富营养化程度水体的净化效果。结果表明,水芹对总磷(TP)有较好的去除效果,初始浓度越高去除率越低,去除率范围53.3%～84.0%;水芹对低于5mg/L的总氮(TN)有较好的去除效果,去除率也随初始浓度升高而降低,去除率范围36.1%～85.7%,如果总氮浓度过高(达到20mg/L左右),去除效果不明显。试验组氨氮(NH3-N)的浓度虽然有明显的降低,但与对照组比没有明显优势,水芹对亚硝酸盐氮(NO2--N)的去除作用不明显,硝化细菌对氨氮和亚硝酸盐氮的去除起主要作用,水芹通过降低水中总氮水平对氨氮和亚硝酸盐氮有一定间接的去除作用。在整个试验过程中,各组高锰酸盐指数(CODMn)维持在较低水平(<3mg/L),未观察到栽植水芹对高锰酸盐指数的降低作用。     

硝化细菌改善鱼苗培育环境增强罗非鱼抗逆性研究

人工引入硝化细菌于罗非鱼鱼苗培育环境中,检测主要水质因子,并测定罗非鱼对主要环境因子抗逆性,研究微生态调控对水质改善和对罗非鱼抗逆性的影响.结果表明,引入不同浓度硝化细菌能显著改善罗非鱼鱼苗培育环境的水质,提高罗非鱼苗的抗逆性.硝化细菌浓度在100 cfu/L时,氨氮含量相对于对照组降低了25.05%,亚硝酸氮含量降低了45.16%,COD值降低了12.33%,显著低于对照组(P<0.05);鱼苗培育成活率相对于对照组高7.58%,体长增长22.18%,体重增加46.15%,显著高于对照组(P<0.05);在氨氮、亚硝酸盐氮、pH、盐度、温度、耐氧抗逆性试验条件下,幼鱼成活率分别为80%、100%、80%、80%和82.5%,缺氧死亡一半的时间为601 s,均显著高于对照组(P<0.05).     

2种复合微生态制剂对大海马幼鱼生长存活及水质影响

以体长为(1.13±0.07)cm的大海马幼鱼为研究对象,观察复合微生态制剂AQ菌和EM菌对大海马幼鱼生长与存活及水中pH、化学需氧量(COD)、氨氮(NH_+~4-N)和亚硝酸盐氮(NO_2~--N)含量的影响。实验设二个处理组AQ菌组(A)和EM菌组(B),均保持养殖水体中有益菌浓度约1×10~4 CFU/mL,另设对照组C(不加复合微生态制剂)。经过35 d实验,结果表明:AQ菌和EM菌对幼鱼的生长及水质影响效果相差不大(P0.05),都可促进幼鱼生长和提高成活率;能够提高水中的pH值,维持在7.7~8.2的适宜范围;有效降低水中COD、NH_4~+-N和NO_2~--N含量,与对照组相比,分别降低了31.0%、51.8%和68.3%,表现出显著性差异(P0.05)。     

不同水循环率对大菱鲆生长和水质的影响研究

研究了封闭循环水养殖系统中不同水循环率对大菱鲆(Scophthalmus maximus)生长和水质变化的影响。试验设置4个水循环率梯度12,24,36,48次/d,大菱鲆初始平均体重为200.36 g。经43 d养殖,12次/d组大菱鲆最终平均体重为277.98 g/尾,而48次/d组达到了296.24 g/尾;12次/d组水体氨氮(TAN)和亚硝酸盐氮(NO2--N)浓度分别为0.41~1.50 mg/L和0.12~0.38 mg/L,而48次/d组分别为0.33~0.56 mg/L和0.05~0.09 mg/L。试验结果显示,提高水循环率可降低系统中氨氮和亚硝酸盐氮的积累速度,优化养殖水质,减小水中有害物质对大菱鲆的胁迫作用,从而加快大菱鲆的生长速度,但对化学需氧量(COD)的去除没有显著影响。     

球形红假单胞菌对三角帆蚌养殖水体水质的影响

将红螺菌科的红假单胞菌应用于三角帆蚌养殖水体,测定水化学环境因子变化情况。结果表明,光合细菌可稳定养殖水体pH,去除氨氮、亚硝酸盐氮、总氮,降低COD,促进水体氮循环,改善养殖水体水质。按水体体积计算,红假单胞菌密度109/mL的菌液合理施用量为0.1%。     

锯缘青蟹苗池微生态环境影响因素的初步探讨

通过对锯缘青蟹苗池微生态环境和水质环境的全过程检测,探讨了总菌数、弧菌数及弧菌数/总菌数的消长规律,并对苗种培育阶段涉及的各种外源因素及控制苗池微生态环境的相关手段的有效性作了初步的探讨。结果表明:苗池水体中总菌数在Z1~Z2少量添加水不换水阶段,呈相对稳定状态,进入Z3后总菌数逐渐增加,最高达3.5×106cfu/m l;弧菌数在Z1培育阶段出现2×102cfu/m l激增至5×104cfu/m l的峰值,第二峰值出现在Z5阶段,达6×105cfu/m l;弧菌数/总菌数比值在育苗起始时仅为0.4%,之后迅速升至30%~40%,在Z5阶段,由于弧菌数量急剧上升,达到50%的高比值;NH4-N与COD检测值在育苗过程中变动较大,两者与弧菌数/总菌数比值呈正相关关系。现行育苗方式中对苗池微生态环境产生影响的主要因素是苗种培育密度,海水、饵料的处理方式和抗生素;净化功能菌和蛭弧菌应用于育苗水体具有抑制弧菌繁殖的效果。     

Effect of Water Exchange Rate on Waste Production in Semi-Intensive Shrimp Ponds During the Cold Season in New Caledonia

An experiment was conducted in six earthen ponds with 20 shrimp/m² ( Litopenaeus stylirostris ) during the cold season in New Caledonia to determine the effect of water exchange rate on characteristics of effluents and pond sediment. The nitrogen budget was established, taking into account the different forms of nitrogen in the water, sediment, feed, and shrimp. Mean water exchange rates ranged from 10 to 23% per day. Increasing water exchange rate did not cause any significant change in the average quality of the rearing environment (water and sediment) during the whole growout period. However, the results showed that increasing exchange rates boosted primary productivity. Compounds produced by the mineralisation and metabolism of organic matter (feces, uneaten feed) were exported as particulate, rather than soluble matter. The nitrogen budget showed that the amount of exported wastes from the pond into the coastal environment was only 40–50% of nitrogen inputs due to nitrogen accumulation in the pond sediments and/or release to the atmosphere. The highest accumulation of dry material, as well as the highest Δ N (concentration of total N at the end of rearing - concentration of total N before rearing), was observed in ponds with the highest WER.     

UV treatment in RAS influences the rearing water microbiota and reduces the survival of European lobster larvae (Homarus gammarus)

The rearing environment is important for a stable production of good quality lobster juveniles. By providing an environment excluding pathogens and dominated by mutualistic bacteria, the probability of developing healthy host-microbe relationships and produce healthy juveniles is increased. Disinfection of water and sudden increase in the supply of organic matter in culture tanks are processes that open for uncontrolled microbial regrowth in the rearing water. This increase the variability in the development of the microbiota between replicate rearing tanks and promotes selection for potentially harmful opportunistic bacteria. In two start feeding experiments with European lobster (Homarus gammarus) we compared the bacterial environment in three types of rearing systems: a recirculating aquaculture system (RAS) with UV treatment directly in front of the rearing raceways, a RAS without disinfection, and a conventional flow through system (FTS). The RAS with no disinfection was hypothesised to stabilise the microbiota of the rearing water, select against opportunistic bacteria, and reduce variability in production outcome between replicate tanks compared to the other systems. As predicted, the three different systems developed significantly different compositions of the microbiota in the rearing water and the larvae. On average, the survival of larvae in RAS without disinfection increased with 43 and 275 %, in the first experiment, and 64 and 18 % in the second experiment, compared to RAS with UV and FTS, respectively. Also, the RAS without disinfection showed less variability in the survival of larvae between replicate tanks and batches compared to the other treatments. The results are promising for controlling the microbiota of the rearing water to improve, increase and stabilise the production of marine larvae by competent use of water treatment and selection regimes. Based on the presented and previous work, RAS is recommended over FTS, and in RAS it is recommended to avoid point-disinfection of the recirculating water, to provide a stable and beneficial microbial environment in the cultivation of marine larvae.     

双棘黄姑鱼人工育苗技术的研究

对双棘黄姑鱼催产、孵化和育苗技术进行了试验,并观察描述了其仔、稚鱼及幼鱼早期发育的主要特征.通过对饵料强化及水质控制等育苗关键技术的改进,在水温24.5～28.5℃、盐度26～30的条件下,共培育出平均全长30.92 mm的鱼苗约2.45×105尾.     

不同消毒剂对凡纳滨对虾育苗水质和菌群结构的影响

该研究使用碘(I2)、二氧化氯(ClO2)、甲醛溶液(HCHO)和漂白粉[Ca(ClO)2]4种常用消毒剂对凡纳滨对虾(Litopenaeus vannamei)育苗海水处理后,研究了不同发育期育苗水体总菌和弧菌数量、氨氮和亚硝酸氮含量、幼体成活率以及水体和幼体菌群的变化.结果显示:1)甲醛组水体的总菌数较低,且弧菌数...     

美洲鲥当年鱼种池塘大棚越冬养殖试验

于2017—2019年采用在池塘上方搭建简易保温大棚的方式开展了美洲鲥当年鱼种越冬养殖试验,研究探讨了越冬养殖相关的技术参数。结果显示:搭建保温大棚后,冬季池塘水温可保持在10℃以上,在美洲鲥当年鱼种(0+龄鱼种,平均体长12.45~16.65 cm,平均体质量27.29~66.41 g)放养密度为1518~2970尾/亩(15亩=1 hm^2,下同)和81.04~100.78 kg/亩的条件下,在越冬前中期(12月至次年3月中旬),日投饲量在0.8~1.6 kg/亩,越冬后期(次年3月中旬至4月上中旬),日投饲量也由2.0 kg/亩左右迅速增加到4.0~5.0 kg/亩。经过125~130 d的越冬养殖,鱼种平均体长达17.48~21.19 cm,增长28.04%~40.40%,平均体质量77.57~137.96 g/尾,增加了106.53%~184.24%,鱼种的体长和体质量特定生长率分别为(0.193~0.261)%/d和(0.585~0.804)%/d,日均增长量和日增重分别为0.036~0.039 cm/d和0.387~0.572 g/d;收获时美洲鲥鱼的肥满度为1.42~1.43 g/cm3,养殖成活率为89.29%~94.81%,饲料系数为1.50~1.65,亩产量为198.50~205.68 kg。试验结果表明,在江浙地区,养殖池塘上方搭建保温大棚后,冬季池塘水温(10~20℃)在美洲鲥当年鱼种的适宜水温范围,能获得较理想的越冬养殖效果。     

Acclimation Induced Responses of SDH Activity of Tilapia (Oreochromis mossambicus) Following Introduction in a New Pond Habitat

Responses of the major mitochondrial respiratory enzyme succinate dehydrogenase (SDH) activity in gill and muscle tissue of tilapia (Oreochromis mossambicus) were investigated upon their transfer to a new pond habitat. Sixty healthy adult fish were procured from each of the three ponds used and were distributed in three cages in equal numbers; the cages were placed in each of the other two ponds as well as into original rearing pond. Four fish were removed from each cage every week and were sacrificed for the assay of SDH activity in gills and muscles. Transfer of fish from a stress condition to a benign environment and vice versa resulted in an increase and decrease in SDH activity of fish, respectively. The intensity of increase upon transfer was again dependent upon the amount of stress in the new habitat. In general, the SDH activity of the test fish strongly correlated with the ammonia concentration (P?<?0.05) of water regardless of habitats. Time required for the introduced fish to acclimatize with new environmental conditions was dependent upon the environmental milieu of both its initial and final place of rearing and hence their physiological states. Differences in water quality, especially ammonia concentration, between its original place of rearing and the place of transfer were found to be responsible for the differences in acclimation period of two or three weeks. Relatively less difference in ammonia (2.68 for gills and 3.20 for muscles) between the initial place of rearing and new habitat resulted in acclimation of the fish one week earlier (second week) than the relatively wide difference (4.46 for gills and 5.62 for muscles) for third week. It may be reasonable to conclude that the varied responses of the mitochondrial respiratory enzyme of exogenously introduced fishes with the differences in the water quality—especially the ammonia concentration of ambient water between the original fish holding pond and growout pond—can be used to predict the time that will be required for the exogenously introduced fish to fully acclimatize with the new habitat.     

黑鮶控光育苗技术研究

利用体重1～4kg的怀仔黑亲鱼56尾,完全人工控制弱光,长流水、自然水温培育,共产仔272万尾。布池后,根据不同日龄投喂轮虫、卤虫无节幼体、配饵和糠虾,控制光照,调节水质,防病治病,及时疏稀,420m~3水体育出平均全长28.8mm的黑苗77.6万尾,总成活率30％。认为,全人工控制光源蓄养亲鱼,溢水法布池,夜间开灯少量投饵,效果较好。     

Hatchery seed production of giant freshwater prawn,Macrobrachium rosenbergii using inland ground saline water in India

The suitability of inland saline water (ISW) from the Lahli‐Baniyani Fish Farm, Rohtak was investigated for the larval rearing of giant freshwater prawn (GFP), Macrobrachium rosenbergii. Six experiments were conducted. In Experiment‐I, 54% of the larvae metamorphosed to postlarvae (PL) in constituted seawater (CSW) whereas total mortality occurred at larval stages (LS)‐II and LS‐III in ISW with salinity of 12 g L^?1. Larvae survived to LS‐IV in Experiment‐II, when ISW was supplemented with K⁺~ SW. In Experiment‐III, total hardness in ISW was reduced serially, but K⁺ ~ SW was supplemented. The larvae did not survive beyond LS‐V. In Experiment‐IV, ISW was amended with different ratios of Mg²⁺/Ca²⁺ and K⁺ ~ SW. The larvae successfully metamorphosed to postlarvae with highest survival of 51.6% in Mg²⁺/Ca²⁺ ratio of 2.5. In Experiment‐V, eight larval cycles were run with water quality used in Experiment V, where all the cycles produced PL's with a survival rate of 20–67%. In Experiment VI, the larvae were reared in Mg²⁺/Ca²⁺ ratio of 2.5 and different levels of K⁺ to optimize its requirement. The ISW amended with K⁺ 80% ~ SW and Mg²⁺/Ca²⁺ ratio of 2.5 was found to be commercially suitable for the seed production of GFP.     

昆明裂腹鱼人工繁殖技术研究

于2003年8月起进行野生昆明裂腹鱼(Schizothorax grahami)亲鱼培育研究,并2009年5月3日—9日进行了人工繁殖技术和鱼苗培育实验。结果显示:野生昆明裂腹鱼在人工驯化养殖条件下,能在池塘内正常生长发育。亲鱼初次性成熟年龄为4龄,雌鱼以5～6龄最佳。采用二次胸鳍基部注射,催产孵化水温为14～17℃,效应时间平均为46h,平均孵化时间为176 h,鱼苗经60 d培育(平均水温14～18℃)体长可达5.05 cm。