分段养殖模式在凡纳滨对虾(Litopenaeus vannamei)养殖过程中的应用

通过测定凡纳滨对虾(Litopenaeus vannamei)生长性能和监测池塘水质变化,研究分段养殖模式在对虾养殖过程中的应用价值。养殖实验在6口池塘内(0.267 hm~2/口)进行,首先在其中2口池塘内进行对虾的中间培育,养殖密度为300×104尾/hm~2。经过36 d和48 d的中间培育后,将对虾先后转移到其他4口池塘内,养殖密度为60×10~4尾/hm~2,分别记为T_1和T_2组。剩余的对虾继续养殖在中间培育池塘内,记为C组。结果显示,经过分段养殖的T_1和T_2组对虾,在分池养殖阶段7 d内,生长速度均明显增加,其特定生长率(SGR)分别达到9.36%/d和6.76%/d;养殖期间,T_1组具有最大的SGR(9.36%/d)和饲料投喂量,然而其饲料系数(FCR)(1.053)高于T_2组(0.822);经过分段养殖的对虾FCR均低于C组(1.082)。在分池养殖阶段的大部分时间,T_2组对虾的SGR高于T_1组;C组NH4+-N、NO_2--N和Chl-a浓度低于T_1组和T_2组,而颗粒物含量(T_PM)和总磷(T_P)高于T_1组和T_2组;T_2组Chl-a含量明显高于T_1组和C组。结果显示,经过48 d中间培育后,即对虾体重约为2 g时进行分池养殖仍可保证对虾在较长时间内保持较大的生长速度,对于饲料的节约具有重要意义。由于分池养殖阶段具有较多的饲料投喂,经过36 d中间培育后的对虾具有最大产量。分池养殖池塘内饲料投喂少于全期养殖,有利于养殖系统的稳定,然而单位时间内投喂量增加则会影响水质。分段养殖模式在提高分池养殖阶段对虾的生长速度和保持水质稳定方面具有重要的应用价值。     

分段养殖模式在凡纳滨对虾(Litopenaeus vannamei)养殖过程中的应用

通过测定凡纳滨对虾(Litopenaeus vannamei)生长性能和监测池塘水质变化,研究分段养殖模式在对虾养殖过程中的应用价值.养殖实验在6口池塘内(0.267 hm2/口)进行,首先在其中2口池塘内进行对虾的中间培育,养殖密度为300×104尾/hm2.经过36 d和48 d的中间培育后,将对虾先后转移到其他4口池塘内,养殖密度为60×104尾/hm2,分别记为T1和T2组.剩余的对虾继续养殖在中间培育池塘内,记为C组.结果显示,经过分段养殖的T1和T2组对虾,在分池养殖阶段7d内,生长速度均明显增加,其特定生长率(SGR)分别达到9.36 ％/d和6.76 ％/d;养殖期间,T1组具有最大的SGR (9.36 ％/d)和饲料投喂量,然而其饲料系数(FCR) (1.053)高于T2组(0.822);经过分段养殖的对虾FCR均低于C组(1.082).在分池养殖阶段的大部分时间,T2组对虾的SGR高于T1组;C组NH4+-N、NO2-N和Chl-a浓度低于T1组和T2组,而颗粒物含量(TPM)和总磷(TP)高于T1组和T2组;T2组Chl-a含量明显高于T1组和C组.结果显示,经过48 d中间培育后,即对虾体重约为2 g时进行分池养殖仍可保证对虾在较长时间内保持较大的生长速度,对于饲料的节约具有重要意义.由于分池养殖阶段具有较多的饲料投喂,经过36 d中间培育后的对虾具有最大产量.分池养殖池塘内饲料投喂少于全期养殖,有利于养殖系统的稳定,然而单位时间内投喂量增加则会影响水质.分段养殖模式在提高分池养殖阶段对虾的生长速度和保持水质稳定方面具有重要的应用价值.     

PET净水栅对虾池养殖生态环境的影响研究

以PET细丝缠绕成结而形成线性附着基质作为生物净水栅载体材料,在汕头市牛田洋养殖基地设置实验组池塘和对照组池塘(无PET净水栅),于2015年6月至12月定期采集虾池养殖水、浮游植物及对虾样品,测定各项水质指标、浮游植物多样性、对虾生长指标,分析比较PET净水栅对池塘养殖生态环境、凡纳滨对虾(Litopenaeus vannamei)生长情况的影响。结果表明,较养殖初期(6月23日),养殖末期(12月12日)实验池水体氨氮(NH4-N)、硝氮(NO3-N)、亚硝氮(NO2-N)浓度分别下降了68.25%、42.71%、83.51%。浮游植物研究结果表明,对照池和实验池浮游植物平均丰度为5.17×108个·L-1和3.62×108个·L-1,实验池的Shannon-Wiener指数和均匀度指数分别高于对照池8.70%和6.45%(P0.05)。结果表明,实验期间实验池凡纳滨对虾的平均体长和体质量分别高于对照池6.13%和16.67%(P0.01);实验池单位面积饲料用量低于对照池15.44%(P0.01)。     

对虾养殖池塘浮游植物的管理

在稳定池塘水体生态系统和减少水质变动方面,浮游植物的群落结构起着重要作用。池塘水体中溶氧主要来源为浮游植物的光合作用,并吸收大量CO_2、氨、亚硝酸盐及减少硫化氢含量。浮游植物吸附大量的重金属离子,降低其对对虾的毒性。一定量的浮游生物还可避免阳光直射池底,从而抑制丝状藻大量滋生,给对虾提供安静、荫凉的生存环境。浮游植物给浮游动物提供饵料从而达到给对虾提供生物饵料的目的。浮游植物的生长大量吸收养料,抑制病原微生物的生长,使对虾发病率下降。     

不同施肥组合对盐碱地凡纳滨对虾池塘中浮游生物的影响

本实验在山东省东营市黄河口毛蟹繁育中心的养殖池塘的12个陆基围隔(5.5m×5.5m)中进行.在N施加量相等、N/P质量比为10∶1的情况下,实验共设4个处理,分别为全部施加无机肥(NN)、1/3有机肥和2/3无机肥(NO)、2/3有机肥和1/3无机肥(ON)以及全部施加有机肥(OO).凡纳滨对虾(Penaeus vannamei)的放养密度均为33ind/m2.实验结果表明,全部施加无机肥的水体中浮游植物生物量显著高于其他组合,其浮游动物生物量高峰维持时间最短;2/3有机肥与1/3无机肥混施的水体中浮游植物生物量最稳定,而且浮游动物高峰维持时间最长,与其他组合相比能显著提高对虾的净产量;全部施加有机肥的水体中浮游植物多样性指数显著高于其他组合.     

对虾养殖技术之三全程利用生物饵料养殖对虾技术探讨

全程利用生物饵料养殖对虾具有投资少、无污染、对虾生长速度快、无药物残留等优点,本文主要对利用好生物饵料,以实行对虾健康养殖模式,做初步探讨。一、基础饵料对虾养殖池塘中,自然繁殖、人工施肥繁殖、移植的饵料生物以及所有被对虾利用的有机碎屑形成了对虾的基础饵料,并能够被对虾直接利用,对对虾的发育具有决定意义,它们包括藻类、浮游动物及底栖动物等。对虾处于仔虾阶段时,其生长、养殖成活率与池塘内浮游生物、底栖生物有较大的关系,但在正常情况下,仔虾阶段时间较短,几乎所有的养殖池均可满足对虾对饵料的需求以过渡到幼虾。随着…     

不同养殖密度下凡纳滨对虾工厂化养殖排放水研究

为研究不同养殖密度下微生物调控凡纳滨对虾(Litopenaeus vannamei)工厂化养殖排放水的水质状况,设置了3种放养密度(200、400、600尾/m~2),共9口养殖池,跟踪监测了对虾从苗期到养成期不同生长阶段排放水中氨氮、亚硝酸盐氮、硝酸盐氮、硫化物、总磷、COD、重金属等水质指标。结果表明,在3种放苗密度下,当对虾体长8 cm时,排放水的水质基本能达到海水养殖水排放要求的二级标准;当对虾体长≥9 cm时,排放水中无机氮的含量均不符合一级、二级标准。在采用微生物调控的凡纳滨对虾工厂化养殖条件下,放苗密度不超过600尾/m~2时,对虾生长前期养殖水质基本能达到排放要求,生长后期则需要采取一定的养殖废水处理措施,才能达到排放要求。     

对虾工厂化养殖中浮游动物群落结构的变化规律

为了掌握对虾工厂化养殖过程中浮游动物的变动规律，有效管理水体环境质量，提高养殖效益，于2018年8月17日~11月3日，以凡纳滨对虾(Litopenaeus vannamei)为研究对象，分析了对虾工厂化养殖水体中浮游动物群落结构特征、演替规律及其与养殖水体弧菌、浮游微藻和环境因素的关系。结果显示，从实验塘鉴定出21种浮游动物，隶属于4大类，种类最多的为原生动物，共13种，占总数的61.9%；其次为轮虫和桡足类，均为3种，占总数的14.3%；枝角类最少，占总数的5%。整个养殖期，浮游动物的平均密度约为0.71×103 ind./L，平均生物量约为11.72 mg/L。养殖过程中优势种由原生动物、轮虫、桡足类物种逐渐演变成单一的原生动物物种。实验塘浮游动物Shannon-Wiener多样性指数(H′)在0.52~1.64之间波动，前期先降低后升高，后期有所降低。相关性分析显示，浮游动物数量和浮游微藻数量显著负相关(P<0.05)，典范对应分析(Canonical correspondence analysis, CCA)显示，温度、pH、营养盐等是影响浮游动物优势种演替的重要因素。研究结果为深入认识凡纳滨对虾工厂化养殖中浮游动物的群落结构提供了基础数据。     

三种不同方法处理海水养殖凡纳对虾的研究

通过用沙滤、网滤和消毒三种方法处理海水养殖凡纳对虾,在防病、生长、水色稳定性和产量方面均好于未处理海水养殖凡纳对虾的效果。其中沙滤海水实验组从中后期的水质、水色稳定性、换水次数、换水数量、对虾生长速度及产量均好于网滤和消毒实验组。三个实验组对控制WSSV的水平传播,有一定的效果。对于细菌性病原生物,沙滤组和消毒组由于浮游植物和浮游动物结成良好和稳定的生物链,形成较稳定的微生态,在防病上有一定的效果。     

微孔曝气增氧与叶轮增氧机增氧在南美白对虾池塘养殖的应用比较

试验比较了无油滑片式微孔曝气增氧机与传统的叶轮式增氧机对南美白对虾(Penaeus vannamei)养殖池塘的溶解氧、对虾生长及经济效益的影响.经过4个月养殖试验,结果发现,上午10:00时测得的池塘溶解氧都高于5.9 mg/L,但使用微孔曝气增氧的试验塘溶解氧在养殖过程中高于叶轮式增氧机增氧的对照塘;微孔曝气增氧的池塘,7月份和8月份养殖的南美白对虾的全长分别为6.68 cm和8.98cm,体质量分别为3.19g和9.21 g,显著高于叶轮式增氧的池塘(P＜0.05),但9月份收获时终末体长、体质量与对照塘相比无显著差异;试验塘的饲料系数(1.05)低于对照塘的饲料系数(1.16);微孔曝气增氧提高了亩产量,销售利润(3454.1元/亩)是叶轮式增氧机增氧(2308.1元/亩)的1.5倍.微孔曝气增氧是南美白对虾池塘养殖较好的增氧方式.     

Response of biota to aeration rate in low water exchange ponds farming white shrimp, Penaeus vannamei Boone

The response of phytoplankton, zooplankton and benthos to four aeration rates was evaluated in ponds farming white shrimp, Penaeus vannamei Boone, with less than 5% water exchange. Phytoplankton biomass (measured as chlorophyll-fl) was higher in ponds with aeration rates of 0 and 6 h day^?1 than in those with rates of 24 hday^?1. The abundance of zooplankton and benthos (organisms m^?2) were higher in ponds with aeration rates of 0 and 6 h day^?1, and lower in ponds with rates of 12 and 24 h day^?1. The nauplii of different crustaceans, copepods and larval polychaetes were the most abundant organisms of the zooplankton community. Differences in zooplankton composition were observed among treatments. Polychaetes were the most abundant benthic organisms during the culture period. These organisms were more abundant in ponds with lower aeration rates. The guts of shrimp from ponds with aeration rates of 0 and 6 h day^?1 had a higher abundance of zooplankton and benthic organisms than those from the other treatments. That abundance decreased over time in all treatments. Shrimp had better growth in ponds with an aeration of 6 hday^?1. Survival and yield were similar in ponds with aeration rates of 6, 12 and 24 h day^?1, and lower in ponds with rates of 0 h day^?1.     

Growout of Freshwater Prawn Macrobrachium rosenbergii in Fertilized Ponds with Reduced Levels of Formulated Feed

Formulated feed for freshwater prawn farming under semi-intensive conditions is expensive, presenting a significant portion of the farm's operating costs. Production and availability of natural food in earthen ponds may reduce the needs for formulated feed. This paper evaluates growth of freshwater prawn Macrobrachiurn rosenbergii under three feeding regimes, where supplemental feed was reduced and natural productivity of the ponds was increased by a fertilization program that included the addition of lime, phosphorus and nitrogen. Prawns (4.35 g) were stocked into 12 50-m² earthen ponds (6 juveniles/m²) and grown for 84 d feeding on 25% crude protein ration. Chemical and physical water parameters were monitored routinely. Growth and production were similar at 100% formulated feed supplementation with no fertilization and at 50% formulated feed with fertilization, as determined by weight gain, specific growth rate, and net yield ( P >0.05). However, further reduction in feed supplementation (0, 25%, and 50% of feeding rate, respectively, for each subsequent 28-d period) with fertilization, yielded shrimp smaller than market size. Feed conversion ratios were significantly higher ( P 0.05) for the 100% versus the 50% feed supplementation. Survival rate averaged 86% with no significant differences among treatments. Reducing up to 50% of the supplemental feed with added fertilization for increased natural productivity does not reduce yield of M. rosenbergii raised under semi-intensive conditions in northeastern Brazil. Under the local conditions of semi-arid and warm water temperatures (24.0–33.5 C), increasing natural productivity of ponds significantly improves feed conversion ratio, which is reflected in feed cost savings and potential savings of the farm operating cost.     

牙鲆自净式养殖槽中异养细菌和硝化细菌数量及硝化速率

对牙鲆(Paralichthys olivaceus)自净式养殖槽水层和过滤沙层的异养细菌和硝化细菌数量及硝化速率进行了研究，测得装有循环过滤装置的水槽水中和沙粒上异养细菌平均数量分别为2.32×10     

Promotion and contribution of biota in low water exchange ponds farming blue shrimp Litopenaeus stylirostris (Stimpson)

An experimental study was conducted during 20 weeks in Bahia Kino, Sonora, Mexico, in order to evaluate the feasibility of promoting biota in low‐water exchange ponds farming blue shrimp, Litopenaeus stylirostris. The effect of that promotion on the production parameters of cultured shrimp as well as on the water quality parameters was evaluated. Treatments consisted of: (i) ponds fed formulated food (FF), and (ii) ponds fed formulated plus promoted natural food (NFF). Phytoplankton, zooplankton and benthos were effectively promoted during some weeks of the culture period. Growth and feed conversion ratio (15.16 g and 1.79 respectively) were significantly better in treatment NFF than in treatment FF (13.89 g and 2.02 respectively). Differences in some of the water quality parameters were observed among treatments. Phosphates (0.15 mg/L versus 0.53 mg/L), and total ammonia‐N (0.09 mg/L versus 0.12 mg/L) presented greater concentrations in treatment FF than in the NFF.     

看水越冬及其生物学分析

根据黑龙江、吉林地区数十个鱼类越冬池的实测数据 ,从水色、透明度、浮游生物与水体溶氧间的相互关系 ,总结如下规律 :1 水体透明度与浮游植物量负相关 ,与浮游动物量正相关。透明度 <5 0cm者 ,浮游植物丰富而极少浮游动物 ,一般氧气充足 ;透明度 >80cm者 ,多滤食性浮游动物 ,浮游植物少 ,一般溶氧量较低。越冬池透明度以 5 0～ 70cm为宜。 2 根据水体透明度可了解越冬池营养盐的丰欠 ,在越冬中、后期“肥水 (浮游植物多 )易缺肥而瘦水 (浮游动物多 )不易缺肥”。 3 目测冰下水体中鱼类的活动状况和兼测水温变化 ,可为池鱼越冬效果预测提供重要依据     

The Effect of Continual,Nocturnal, or No Aeration on Water Chemistry and Plankton Standing Crops in Highly-Fertilized Sunshine Bass,Morone chrysops × M. saxatilis,Fingerling Production Ponds Without Fish

ABSTRACT

Production of fingerlings from very small fry depends upon an initial high concentration of rotifers followed by high densities of crustacean zooplankton. High fertilization rates lead to increased zooplankton production but often cause poor water quality conditions that aeration may alleviate. This study was designed to determine the effects of constant, nocturnal, and no aeration on water quality, primary productivity, and standing crops of phytoplankton and zooplankton in heavily fertilized nursery-size ponds that contained no fish.

Four 0.04-ha ponds were aerated continually; four ponds were aerated only at night with a 372-W (1/2 hp) paddlewheel aerator; and four ponds were not aerated. For 21 days after they were filled on July 21, 1999, the ponds received 1,224 kg/ha rice bran and 581kg/ha liquid 9-27-0 fertilizer. Water quality variables, primary production, chlorophyll-a and zooplankton were sampled daily.

Constant aeration resulted in several conditions more conducive to survival of fish fry, such as higher zooplankton densities, more moderate temperatures, and safer dissolved oxygen levels than did nocturnal aeration or no aeration. However, the development of a higher standing crop of phytoplankton and higher total ammonia concentrations in the turbulent, constantly aerated ponds resulted in higher un-ionized ammonia levels that were not favorable to survival and growth of fry. The high concentrations of zooplankton that developed in the aerated ponds have good potential for cropping to inoculate other ponds or to provide live foods for tank culture of zooplanktivorous fish.     

Impact of Copper Sulfate on Plankton in Channel Catfish Nursery Ponds

Many fish culturists are interested in applying copper sulfate pentahydrate (CSP) to channel catfish, Ictalurus punctatus, nursery ponds as a prophylactic treatment for trematode infection and proliferative gill disease by killing snails and Dero sp., respectively, before stocking fry. However, copper is an algaecide and may adversely affect phytoplankton and zooplankton populations. We evaluated the effects of prophylactic use of copper sulfate in catfish nursery ponds on water quality and phytoplankton and zooplankton populations. In 2006, treatments of 0 mg/L CSP, 3 mg/L CSP (0.77 mg/L Cu), and 6 mg/L CSP (1.54 mg/L Cu) were randomly assigned to 0.04‐ha ponds. In 2007, only treatments of 0 and 3 mg/L CSP were randomly assigned to the 16 ponds. Ponds treated with CSP had significantly higher pH and significantly lower total ammonia concentrations. Treatment of both CSP rates increased total algal concentrations but reduced desirable zooplankton groups for catfish culture. CSP has been shown to be effective in reducing snail populations at the rate used in this study. CSP treatment also appears to be beneficial to the algal bloom, shifting the algal population to green algae and increasing total algal biomass within 1 wk after CSP treatment. Although zooplankton populations were adversely affected, populations of important zooplankton to catfish fry began rebounding 6–12 d after CSP treatment. Therefore, if CSP is used to treat catfish fry ponds of similar water composition used in this study, fry should not be stocked for about 2 wk after CSP application to allow time for the desirable zooplankton densities to begin increasing.     

Mineral fertilization of carp ponds in polycultural rearing

The fertilization of carp ponds as an important intensification means has been utilized in Europe since the first half of the 19th century, but even in most intensive fertilization the concentration of nitrogen (N) hardly exceeds 2 mg/l and of phosphorus (P), 0.5 mg/l.Polycultural carp growing using intensive mineral fertilization (weekly and every 3 days) has been experimented in the Freshwater Fishery Research Station in Plovdiv in the 1971–1972 period.The greatest zooplankton and benthos biomass and the greatest fish growth per ha water area are obtained with 3-day mineral fertilization with ammonium nitrate, 708 kg/ha and superphosphate, 395 kg per hectar. The average monthly water temperature in the experimental ponds during the vegetation period (June–September) fluctuates between 21.5 and 24.7°C. The oxygen dissolved (O₂) during the day hours changes within the average of 4.9–7.6 ml/l and the aeration is normal for the carp ponds (4.0–8.1 mg O₂/l). The highest average seasonal zooplankton biomass in mixed fertilization (mineral and organic) is 2.437 g/m³. The zooplankton is represented by the following variaties: Rotatoria — Brachionus calyciflorus; Copepoda — Acanthocyclops vernalis and Cladocera — Moina rectirostric. The benthos consists of: chironomid larvae (family Chironomidae, Diptera) and Oligochaetae. The highest average seasonal biomass of the benthos is established with three-day mineral fertilization, 1.472 g/m². The total fish growth with three-day fertilization is 300 kg/ha higher than in the control ponds (without fertilization). The best fishery results have been achieved with three-day fertilization giving a total growth of the fish of 2 730 kg/ha and a food coefficient of 2.8.     

生物渔肥对水泥池浮游生物种群的影响

试验探讨了施用生物渔肥(绿源生)后水体中浮游植物和浮游动物的变化。试验取2个水泥养殖池,其中一个为试验池,施入生物渔肥量为4 g/L,另一个为不施肥的对照池。试验结果表明:施用生物渔肥后试验池中的浮游植物在第2天开始迅速增长,第4天达到生长高峰,比对照池同期增长116.25%,硅藻门取代绿藻门成为优势种群;试验池中的原生动物在第4天达到最大值,比对照池增长16.18%,轮虫、枝角类,桡足类在第6天大量增长,比对照池分别增长30.40%、20.59%和17.46%;试验池浮游生物总量在施入渔肥后的第12天仍高于对照池。本试验条件下,生物渔肥对浮游植物和浮游动物的种类影响不大,但对浮游植物和浮游动物的密度影响较大。     

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.