Monitoring shrimp growth with control charts in aquaculture     

《Aquacultural Engineering》2021

This work proposes a method for the statistical monitoring of the weekly weight of shrimp in a fish farm. The design of control charts for shrimp growth presents several challenges, the main ones being the presence of trend and autocorrelation. Several control charts are proposed, the most efficient being a chart based on the residuals of a second order autoregression whose parameters vary with the week. A control chart with less computational complexity is also provided. It is simply based on growth rates and works well at detecting negative weight changes. Real data from a large shrimp farm has been used for both the design and the evaluation.  相似文献   

Lethal Effects of Elevated pH and Ammonia on Early Life Stages of Hybrid Striped Bass     

《Journal Of Applied Aquaculture》2013,25(3-4):81-100

Hybrid striped bass larvae (striped bass, Morone saxatilis, ♀ x white bass, M. chrysops, ♂) are often stocked into fertile culture ponds. High rates of photosynthesis may result in elevated pH which can be lethal to fry and can affect the toxicity of ammonia. Six-hour static toxicity tests were performed on hybrid larvae of various ages to determine the toxicity of elevated pH and the effects of elevated pH on ammonia toxicity. Six-hour mortality threshold pH's with no measurable ammonia were estimated for various age larvae and found to be between pH's 9.8 and 10.2 for D2 (Dl is day of hatch), between 9.0 and 9.4 for D4, between 8.8 and 9.2 for D13, and between 9.2 and 9.4 for D20 fish. The addition of 0.7% NaCl had no effect on the toxicity of elevated pH to D2 or D4 fish but caused a significant reduction in the mortality of Dl3 and D20 fish exposed to high pH. The tolerance to elevated pH decreased as ammonia concentration increased. Sub-lethal un-ionized ammonia concentrations increased the toxicity of elevated pH, suggesting an interaction of pH and un-ionized ammonia toxicity.  相似文献   

Effects of binder type and binder addition on the growth of juvenile Palaemonetes varians and Palaemon elegans (Crustacea: Palaemonidae)     

Jorge Palma  Dominique P. Bureau  José Pedro Andrade 《Aquaculture International》2008,16(5):427-436

This investigation compared the effects of using two binders of no nutritional value, lignosol and agar, and the binding method, microbinding and microcoating, on the growth of juvenile Atlantic ditch shrimp, Palaemonetes varians, and rockpool prawn, Palaemon elegans. Shrimp were fed one basal diet which varied solely in binder type and method of inclusion (Diet A, with lignosol added by microbinding, Diet B, with agar added by microbinding, and Diet C with lignosol added by microcoating) for a period of 45 days. At the end of the experiment significant differences in the final wet weight were found between shrimps fed Diet A and Diet C and between shrimps fed Diet B and Diet C (P < 0.001), but no significant differences were found between Diet A and Diet B (P > 0.05). These results were verified for both species. Significant differences were found between the linear regression slopes of the three tested diets for P. varians (F _3,411 = 3.41; P < 0.04), and for P. elegans (F _3,431 = 10.51; P < 0.0003). Palaemon elegans grew faster than P. varians and at the end of the experiment significant differences were found between the final wet weight of the two species (F _3,842 = 48.17, P < 0.0001). The growth parameters analysed, weight gain (WG), thermal-unit growth coefficient (TGC), and food conversion rate (FCR) were always higher for P. elegans. Results indicate that use of either lignosol or agar, added to the diet by microbinding, is advisable.  相似文献   

我国市售虾酱产品品质分析与评价          下载免费PDF全文

田龙  赵玲  孙慧慧  胡梦月  赵玉巧  曹荣 《渔业科学进展》2024,45(1):224-233

为了解我国市售虾酱产品的品质现状，探究不同品种虾酱之间的品质差异，采集了32种市售虾酱，进行了感官评价和水分、盐分、蛋白质、氨基酸态氮等理化指标的检测，对品质相关数据进行了统计分析和主成分分析，并进一步采用电子鼻和气相–离子迁移谱(GC-IMS)对气味进行了分析。结果表明，市售虾酱色泽和质地差异相对较小，而气味差异较大。理化指标中，市售虾酱的氨基酸态氮含量变异系数为33.91%，离散程度最大。在主成分分析中，提取到3个主成分，累计方差贡献率达82.32%，表明能够涵盖虾酱品质的基本信息，水分、氨基酸态氮、气味是影响虾酱综合品质的关键指标。电子鼻聚类热图表明，在欧式距离4.03处可将32种虾酱聚为4类，原料是影响聚类的主要因素。对海银虾、蜢子虾和白虾3种原料的虾酱进行GC-IMS分析，共鉴定出63种挥发性成分，主要是醇类。研究结果可为虾酱产品品质评价与生产工艺改进提供参考。  相似文献   

对虾养殖中新生残饵耗氧动态及其规律的研究   总被引：2，自引：0，他引：2  

孙耀  杨琴芳  崔毅  李健 《中国水产科学》1996,3(4):53-59

本文根据实验模拟研究的结果，估算了由配合饵料和贻贝肉形成残饵后３６天时间内的耗氧量，并讨论了其耗氧动态和规律。残饵耗氧量的变化范围为４．０９～１７．６１ｇ／ｋｇ·ｄ。残饵耗氧曲线随残饵形成时间的不同而显著变化，且始终呈二次曲线衰减形式，在其演变过程中，该二次曲线方程的二次项系数由负数逐渐演变为正数，并最终接近于污染虾塘底质的耗氧曲线。配合饵料和贻贝肉的耗氧曲线变化形式相近，但程度上存在较大差异。另外，本文还初步探讨了残饵的耗氧高峰期，估算了残饵在虾塘底质总耗氧量中的作用。  相似文献   

显微注射生长激素基因导入中国对虾（Penaeus chinensis）受精卵的研究   总被引：4，自引：0，他引：4  

刘萍  孔杰  王清印  李健  杨丛海  梁利群  孙孝文 《中国水产科学》1996,3(4):35-38

本实验采用显微微量注射方法，交羊生长激素基因导入中轻地虾受精卵，受精卵发育到蚤状幼体第三期后采样检测。ＰＣＲ检测结果表明：７个样品共９３尾幼体，有３个样品呈出阳性信号，基因转移比率至少在３％以上。同时斑点杂交结果也证明有两个明显阳性斑点。  相似文献   

Shrimp and fish pond soils: processes and management   总被引：7，自引：0，他引：7  

Yoram Avnimelech  Gad Ritvo 《Aquaculture (Amsterdam, Netherlands)》2003,220(1-4):549-567

The pond bottom soil and the accumulated sediments are integral parts of ponds. Concentrations of nutrients, organic matter and microorganism density in the pond bottom are several orders of magnitude greater than in the water. The accumulation of organic sediments may limit pond intensification. The intensive organic matter degradation at the pond bottom and high sediment oxygen demand exceeds the oxygen renewal rate. This leads to the development of anoxic conditions in the sediments and at the sediment–water interface. A series of anaerobic processes, affected by the redox potential of the system, are taking place. A large number of potentially toxic materials are generated. Among those are organic acids, reduced organic sulfur compounds, reduced manganese and sulfides.

Shrimp, as animals that normally live on or near the bottom, are exposed to conditions on the pond bottom. Exposure to toxic materials endanger the well being of the cultured shrimp. Reduced feeding, slower growth, mortality and possibly higher sensitivity to disease are reported.

The rational use of aerators to minimize the area of sludge accumulation, construction of ponds to trap sludge, stirring sediments, chemical poising of the redox system and environmentally accepted treatment and reuse of drained sediments are means to control the conditions at the pond bottom.  相似文献   

Grow-out of sandfish Holothuria scabra in ponds shows that co-culture with shrimp Litopenaeus stylirostris is not viable     

Johann D. Bell  Natacha N. Agudo  Pascal Blazer  Dominique Pham 《Aquaculture (Amsterdam, Netherlands)》2007,273(4):509-519

We examined the potential for producing the large numbers of sandfish (Holothuria scabra) needed for restocking programmes by co-culturing juveniles with the shrimp Litopenaeus stylirostris in earthen ponds. Our experiments in hapas within shrimp ponds were designed to detect any deleterious effects of sandfish on shrimp, and vice versa. These experiments showed that a high stocking density of juvenile sandfish had no significant effects on growth and survival of shrimp. However, survival and growth of sandfish reared with shrimp for 3 weeks were significantly lower than for sandfish reared alone. Increased stocking density of shrimp also had a significant negative effect on survival and/or growth of sandfish. A grow-out trial of juvenile sandfish in 0.2-ha earthen ponds stocked with 20 shrimp post-larvae m^− 2, and densities of sandfish between 0.8 and 1.6 individuals m^− 2, confirmed that co-culture is not viable. All sandfish reared in co-culture were dead or moribund after a month. However, sandfish stocked alone into 0.2-ha earthen ponds survived well and grew to mean weights of ∼ 400 g within 12 months without addition of food. The grow-out trial demonstrated that there is potential for profitable pond farming of sandfish in monoculture. Further research is now needed to identify the optimal size of juveniles, stocking densities and pond management regimes.  相似文献   

鱼粉质量对中国对虾、真鲷、饲料转化率和蛋白质消化率的影响     

梁明青  AndersAksnes 《海洋水产研究》2001,22(4):75-79

IntroductionInherent to the practice of intensive aquaculture is the generation of wastes having immediate and verybroad effects on the aquatic environment.There is a growing consensus about the need to reduce waste pro-duction in aquaculture to minimize the negative impacts on the environment.Nitrogen(N) and phosphorus(P) wastes are major concerns for many aquaculture operations.In the past,formulation of diets in intensive aquaculture was often aimed at meeting requirements formaximum growt…  相似文献   

Sperm maturation and capacitation in the open thelycum shrimp Litopenaeus (Crustacea: Decapoda: Penaeoidea)     

Jorge Alfaro  Karol Ulate  Maribelle Vargas 《Aquaculture (Amsterdam, Netherlands)》2007,270(1-4):436-442

Transmission electron microscopy was applied to sperm removed from males and females belonging to Litopenaeus vannamei, L. stylirostris and L. occidentalis. It was discovered that a region named filamentous meshwork (FM), located between the nucleus and the hemispherical cap, develops differently in these three closely related species. In L. vannamei, the FM is synthesized in the male reproductive system, but seems to complete its formation after mating. In L. stylirostris, the FM region was not present in spermatophores collected from males or in sperm from the thelycum. In L. occidentalis, the FM region is fully developed in male sperm. It is suggested that completion of the FM is required for acrosome maturation, and the process continues after mating in some species of Litopenaeus. In vitro induction of the acrosome reaction in sperm from males and females of L. occidentalis demonstrated for the first time that reactivity is significantly superior in sperm cells that have been attached to the open thelycum for some hours, as compared to sperm in males (prior to transfer). This finding suggests that matured sperm cells of L. occidentalis become capacitated to react against egg water after mating.  相似文献