卵形鲳鲹海水网箱养殖技术

卵形鲳鲹属鲈形目、鲹科、鲳鲹属，又名金鲳、黄腊鲳等，因其肉质细嫩、味道鲜美、营养丰富，深受东南亚市场的青睐。卵形鲳鲹具有生长速度快、适应环境能力强、成活率高等特点，一般当年养殖，当年即可达到上市商品规格，经济效益显著，因而深受养殖业者的欢迎。随着人工育苗与养殖技术的发展，卵形鲳鲹现已成为我国南方沿海地区广泛养殖的一种经济鱼类。卵形鲳鲹的养殖方式主要有网箱养殖、池塘养殖、鱼媪养殖等，近几年来在我国海南和广东等地沿海进行网箱养殖的规模不断扩大，因此，下面主要就卵形鲳鲹的网箱养殖技术做一个简单的总结和介绍。     

卵形鲳鯵海水网箱养殖技术

卵形鲳鯵属鲈形目、鱼参科、鲳鯵属,又名金鲳、黄腊鲳等,因其肉质细嫩、味道鲜美、营养丰富,深受东南亚市场的青睐。卵形鲳鯵具有生长速度快、适应环境能力强、成活率高等特点,一般当年养殖,当年即可达到上市商品规格,经济效益显著,因而受到养殖业者的欢迎。随着人工育苗与养殖技术的发展,卵形鲳鯵现已成为我国南方沿海地区广泛养殖的一种经济鱼类。     

彩虹鲷网箱养殖技术要点

彩虹鲷属鲈形目,罗非鱼属,属内种间杂交育出的新品种,其体色诱人,生长速度快,食性广泛,适应性强,肉味鲜美,抗病强,经济效益好,为一般养殖鱼类价格的2～4倍,具有广泛的养殖推广前景,尤其适宜于网箱养殖。近几年,彩虹鲷网箱养殖在平度各大水库发展很快,已达到40多箱。2006年我们在尹府水库投放彩虹鲷网箱5只,     

花尾胡椒鲷的生物学特性及网箱养殖技术

花尾胡椒鲷（Plectorhynchus cinctus）,英文名：Grunt,俗称：打铁母、假包公、斑加吉,隶属于鲈形目,石鲈科,胡椒鲷属。主要分布于印度洋和北太平洋西部,我国黄海、东海和南海均产,以南海产量为最多。为亚热带和温热带浅海底层鱼类。该鱼肉质细嫩、味道鲜美、市场价值高,是国内及港台市场上畅销的水产品,目前已成为广东、福建及浙江沿海海水养殖的优良鱼类品种。     

海水网箱养殖鲈鱼技术

<正> 鲈鱼属于浅海内湾性鱼类,喜栖息于河口或淡水处,是一种重要的食用经济鱼类,它生长快、肉细、味美,营养价值高,是海水网箱养殖的优良品种。1994年,作者在温岭市乐清湾海区进行了网箱养殖鲈鱼探索,取得了一定的经济效益,现将其养殖技术简要介绍如下:     

真蛸海水网箱养殖技术试验

真蛸(Ooctopus ocellatus),俗名真章、章鱼、红章,是一种很有养殖潜力的水产经济品种。但养殖周期不易过长,因真蛸寿命很短,只有12￣18个月当体重超过3kg时,死亡开始增加,养殖就导致减产。从2006年6月份开始对真蛸养殖进行试验,现将海水网箱养殖试验结果做如下介绍:     

花尾胡椒鲷海水网箱养殖技术

花尾胡椒鲷（Plectorhinchus cincuts）俗称花加志、打铁母，其肉质结实、营养丰富、是近年来新开发的海水养殖品种。作者于2005年进行试养，体长7～10cm的花尾胡椒鲷经养殖10～13个月，平均体重可达600g～650g。现将花尾胡椒鲷养殖情况介绍如下。     

海水深水网箱常规养殖技术

一、养殖海区的选择选择２０米等深线以内的半开放海区（至少有一到二处自然屏障物），泥沙质底较平坦海区，潮流通畅，流速在５０～１００厘米／秒；表层水温８～２８℃，最适水温２０～２６℃；pH７．８～８．６；透明度０．３米以上，溶解氧５毫克／升以上。主要水质指标不超过鱼类养殖要求的安全浓度及国家海区水质标准。二、网箱海区布局网箱设置面积不宜超过养殖海区面积的１０％。网箱布局应与流向相适应，可使潮流通畅。为了便于操作管理，可以两组并列排列，组与组间距８０～１００米，中间可设管理通道。列与列之间应在５０米以…     

卵形鲳鲹网箱养殖技术

卵形鲳鲹(Trachinouts ovatus)属于鲈形目、鲈亚目、鲳鲹亚科、鲳鲹属,俗称红三、金鲳、短鳍鲳、黄腊鲳,是我国台湾省海水网箱养殖的主要品种之一。卵形鲳鲹具有生长速度快、适应环境能力强、养成成活率高等特点,其肉为白色,较细嫩,肉质鲜美可口,为名贵海产经济鱼类之一;一般当年放养体     

斜带髭鲷海水网箱养殖技术总结

斜带髭鲷（图见彩中插2）隶属于鲈形目、石鲈科、髭鲷属,俗称打铁婆、包公鱼,为近海中下层鱼类,斜带髭鲷活鱼运输方便、成活率高,价格多年稳定在40～50元／千克。本人从2003年就开始试养斜带髭鲷,多年在福鼎沙埕港不同海区养殖摸索,现将斜带髭鲷海水网箱养殖情况介绍如下：     

Optimization of Feeding Rate for Hatchery-Produced Juvenile Gilthead Sea Bream Sparus aurata

Abstract.— A 61-d growth trial (five 11-d feeding periods) was conducted to determine the effects of feeding rate on growth, feed utilization, morphology, and body composition of the gilthead sea bream Sparus aurata . Gilthead sea bream juveniles with an average initial body weight of 3 g were fed a commercial diet (51% crude protein, 11% crude fat) at rates of 0.5, 1.0, 1.5, 2.0, 2.5, or 3.0% of their body weight (BW) per day in two equal meals. Water temperature was approximately 21.4 C throughout the experiment. Each ration was administered to triplicate groups of 60 fish, with ration readjusted every 11 d. Growth rate was measured as specific growth rate (SGR). Survival rate and coefficient of variation did not differ significantly among the groups fed different rates. Body weight, condition factor, and hepatosomatic and viscerosomat-ic indices displayed significant increases with increasing feeding rate from 0.5 to 3.0% BW/d. Fish fed 0.5% BW/d had significantly higher moisture and ash and lower protein contents than those fed at higher rates. Moisture and protein contents were not significantly different for fish fed at the highest feeding rates (2.0, 2.5, and 3.0% BW/d). Lipid contents increased significantly with increasing feeding rate from 0.5 to 3.0% BW/d. The SGR showed a curvilinear significant increase when the feeding rate was increased from 0.5 to 3.0% BW/d. Feed efficiency (FE) increased significantly to a maximum value with increasing feeding rate from 0.5 to 2.0% BW/d and decreased significantly with increasing feeding rate from 2.5 to 3.0% BW/d. Based on the data obtained, feeding rates of 2.3% and 0.6% BW/d are recommended as optimum and maintenance rations, respectively.     

Predicting aquaculture waste from gilthead seabream (Sparus aurata) culture using a nutritional approach

A model to estimate the waste production from sea cage culture was established. Using known feed inputs of nitrogen, phosphorus and organic matter, the model quantifies waste discharge from seabream culture. Daily feed intake and growth in Sparus aurata fed a commercial diet with known composition were measured and found to be dependent on fish weight and water temperature. Digestibility of the commercial feed was measured using chromic oxide as a marker and collection of feces by stripping. The proximate composition of Sparus aurata at different sizes was determined and nitrogen and phosphorus content were on average 28.5 and 7.2 g·kg⁻¹ body mass, respectively. Excretion of ammonia-nitrogen and inorganic phosphorus after metabolic processes was calculated as the difference.     

Economic optimisation in seabream (Sparus aurata) aquaculture production using a particle swarm optimisation algorithm

The purpose of this study is the economic optimisation of seabream farming through the determination of the production strategies that maximise the present operating profits of the cultivation process. The methodology applied is a particle swarm optimisation algorithm based on a bioeconomic model that simulates the process of seabream fattening. The biological submodel consists of three interrelated processes, stocking, growth, and mortality, and the economic submodel considers costs and revenues related to the production process. Application of the algorithm to seabream farming in Spain reveals that the activity is profitable and shows competitive differences associated with location. Additionally, the applications of the particle swarm optimisation algorithm could be of interest for the management of other important species, such as salmon (Salmo salar), catfish (Ictalurus punctatus), or tilapia (Oreochromis niloticus).     

Microbial Growth Models in Gilthead Sea Bream (Sparus aurata) Stored in Ice

ABSTRACT

This study analyzes microbiological changes in whole, ungutted farmed gilthead sea bream (Sparus aurata) stored for an 18-day period in ice using traditional methods for mesophilic aerobic bacteria, psychrotrophic, Pseudomonas spp., Aeromonas spp., Shewanella putrefaciens, Enterobacteriaceae, sulphide-reducing Clostridium (Clostridia), and Photobacterium phosphoreum in muscle, skin, and gills, evaluating their seasonal differentiation. Two different statistical models were used to analyze microbiological growth. Simultaneously, physicochemical parameters such as the temperature, pH, biological oxygen demand (BOD), total dissolved solids, salinity, ammonia nitrogen, and total phosphorus content of growing waters were analyzed. The results showed that by the end of the storage time, specific spoilage bacteria (SSB) such as Pseudomonas spp., Aeromonas spp., and S. putrefaciens as H₂S-producing bacteria were dominant in sea bream harvested in temperate water in the Canary Islands. Muscle tissue had the least contamination, followed by skin and gills. The values of the analyzed seawater parameters were constant during the four seasons, except that the temperature showed a small difference between winter and summer. Seasonal effects were observed among the fish analyzed, suggesting that the lower levels of contamination detected in winter may have been due to the slight difference observed in water temperature in that season.     

Disinfection of Sparus aurata eggs with glutaraldehyde

This study was conducted to determine suitable conditions fordisinfecting eggs of gilthead sea bream (Sparus aurata)with glutaraldehyde. Effects of the developmental stage (4–8 cells,morula, blastopore closure or heart beating), of the concentration (C = 200,300or 400 ppm) and of the duration of the glutaraldehyde treatment (T= 2 to 10 min) were investigated. Before the blastopore closurestage, egg manipulation and treatment induced mortality. After this stage, thetoxicity of the glutaraldehyde treatment was negligible if the value of theproduct C × T was less than 1000. Above this value, the percentage ofhatching and of normal larvae decreased and the percentage of imprisoned larvaeincreased. Toxic effects of glutaraldehyde varied according to the egg qualityat the time of the treatment. It was concluded that 200 ppmglutaraldehyde for 4 min, at the blastopore closure stage or attheheart beating stage, were acceptable conditions for disinfecting gilthead seabream eggs at 18 °C.     

Disinfection of Sparus aurata eggs with glutaraldehyde

This study was conducted to determine suitable conditions fordisinfecting eggs of gilthead sea bream (Sparus aurata)with glutaraldehyde. Effects of the developmental stage (4–8 cells,morula, blastopore closure or heart beating), of the concentration (C = 200,300or 400 ppm) and of the duration of the glutaraldehyde treatment (T= 2 to 10 min) were investigated. Before the blastopore closurestage, egg manipulation and treatment induced mortality. After this stage, thetoxicity of the glutaraldehyde treatment was negligible if the value of theproduct C × T was less than 1000. Above this value, the percentage ofhatching and of normal larvae decreased and the percentage of imprisoned larvaeincreased. Toxic effects of glutaraldehyde varied according to the egg qualityat the time of the treatment. It was concluded that 200 ppmglutaraldehyde for 4 min, at the blastopore closure stage or attheheart beating stage, were acceptable conditions for disinfecting gilthead seabream eggs at 18 °C.     

Optimization of Artemia Metanauplii on Growth and Survival of Gilthead Sea Bream Larvae Sparus aurata

–Growth, feed efficiency and survival of gilthead sea bream Sparus aurata larvae fed exclusively various levels of enriched Artemia during the period 25 DPH-34 DPH were investigated. Larvae had an average initial fresh body weight (BW) of 4.99 mg and were fed on Artemia at rates of 20, 35, 50, 65, and 80% of their body weight per day, in two equal meals. Each ration was administered to duplicate groups of 1,000 larvae, with ration readjusted every second day. Feeding rate had a significant effect on larval survival, which was lower in larvae fed the 20 and 35% BS/d rations. The specific growth rate (SGR) showed a curvilinear significant increase when the feeding rate was increased from 20 to 65% BW/d, but there was no improvement when the feeding rate was increased from 65 to 80% BW/d. Percent feed efficiency (FE) decreased significantly from a maximum value at 20% ration to 80% BW/d but at 65% and 80% rations the values of FE were not significantly different. Optimum ration (minimum quantity of Artemia concomitant with maximum larval growth) was estimated close to 65% BW/d. The significance of the results is discussed in relation to potential economics of Artemia cysts use in commercial hatcheries.     

Different Packaging Conditions to Improve Shelf Life of Filleted Gilt-Head Sea Bream (Sparus aurata)

Abstract

Shelf life of cultured gilt-head sea bream fillets (Sparus aurata) in over-wrap, vacuum and gas mixture packages stored during 27 days at 1±1°C was compared. The gas mixtures used contained CO₂, O₂, and N₂ at different percentages (0% O₂ + 50% CO₂ + 50% N₂; 10% O₂ +50%CO₂ +40%N₂;20%O₂ +50%CO₂ +30%N₂;30%O₂ +50% CO₂ + 20% N₂).

The evolution of the freshness degree of the packaged fillets was carried out by measurements of total volatile bases (TVB), trimethylamine (TMA), Tiobarbituric Acid Reactives Substances (TBARS), K _i and H values, psychrotrophic bacterial counts and sensory evaluation (color, odor, flavor).

Fish fillets were obtained 3 hours after harvesting with the best handling practices. As a consequence of this, the initial bacterial load was very low. The inhibitory effect of CO₂ on bacterial growth was very effective, keeping very low counts throughout all the storage period. Gas packages without O₂ and vacuum packages presented very low oxidation, whereas TBARS values in over-wrap and 10%, 20% and 30% O₂packaged fillets increased according to the oxygen content in the package. K_i value and specially H value differentiated very well among aero-bically stored fillets, vacuum and modified atmosphere packaging. TVB and TMA productions were poor freshness indicators, since no differences were found among treatments. Sensory quality of fillets deteriorated faster in over-wrap than in vacuum and gas packages. Modified atmospheres containing 20 and 30% O₂ were given lower sensory scores than vacuum packages, since they gave rise to yellowness of the fillets and off-odors and off-flavors.

In summary, modified atmosphere packaging of filleted gilt-head sea breams with a gas mixture consisted of 50% CO₂ + 50% N₂ gave rise to an important extension of shelf life compared to over-wrap packaging, vacuum and modified atmosphere packaging with gas mixtures containing O₂. This was due to the very low oxidation levels produced during the storage, the lower H value as a consequence of a minor production of Hx and the great inhibition on microbial growth.