鲟鱼流水生态养殖中的疾病防控与健康管理研究

流水生态养殖环境中华鲟疾病防治与健康管理。对鲟鱼生态养殖进行了分析,分析了鲟鱼常见病害的分类、特点及其对养殖产业的影响。疾病的早期监测和诊断,包括水质监测、免疫接种技术和早期诊断方法。强调鲟鱼健康管理和营养要求、鲟鱼饲料和营养要求、疾病预防管理、养殖密度和环境适应性。为鲟鱼养殖业提供可行的疾病防控和健康管理实践,为养殖技术创新和疾病防控新技术提供建议。

大刺鳅简易式循环水生态养殖系统养殖试验

本试验用的循环水生态养殖系统包括面积约6.7 m^(2)、深0.8~1.0 m的养殖池、净化池、过滤设备、NFT管道水培装置和气动力系统等设备。试验组和对照组分别采用空气能和普通加热设备。放养前10~15 d,在NFT管道培育装置中移入培育好的绿萝(Epipremaum aureum),向养殖系统中投放硝化细菌、光合细菌、芽孢杆菌,待菌膜成熟和植物根系长成后进行养殖实验。在水温25~30℃下,向养殖池中分别放养体质量2~3 g、7~10 g和20~50 g的大刺鳅(Mastacembelus armatus),密度500尾/m^(2)、300尾/m^(2)和150尾/m^(2),饲养60 d、90 d和90 d,研究循环水生态养殖系统对大刺鳅苗种培育、鱼种和成鱼养殖效果的影响。结果显示,试验组的成活率比对照组分别高16.29%(苗种培育)、12.38%(鱼种养殖)和7.05%(成鱼养殖);与对照组相比,试验组用水量减少了88.04%~91.70%,加热保温成本降低了89.16%~92.48%;饲料系数下降了14.15%~19.10%,产量提升至7.57kg/m^(2)。该模式可以有效降低能耗需求,减少用水量,提升养殖效率等,可作为大刺鳅规模化养殖的重要参考。

池塘循环水生态化养殖技术分析

渔业养殖作为多数地区发家致富的重要产业模式,由于受到气候和水源等因素的影响难以向集约化和规模化发展,阻碍水产养殖产业的健康发展。因此,文章提出了池塘循环水生态养殖技术,介绍此技术的常用模式和特点,提出此技术实际应用中需要注意的技术要点,以及开展养殖工作时的注意事项,总结应用此生态养殖技术所需的环境、社会和经济效益等,以供参考。

陆基循环推水水槽式生态养殖试验初探

为验证陆基循环推水水槽式生态养殖的具体养殖效果,促进其在浙北地区进一步推广应用,对陆基循环推水水槽式生态养殖和常规土塘养殖的养殖效果进行了比较试验。结果表明,相对于常规土塘养殖,陆基循环推水水槽式生态养殖的水产品养殖密度大幅度提高,溶氧量表现更优,饵料比表现更佳,经济效益更好,综合性价比更高,符合当前水产品养殖方向,在浙北地区具有一定的推广应用价值。

A novel male-associated marker for sex identification in Ussuri catfish Pseudobagrus ussuriensis

The Ussuri catfish Pseudobagrus ussuriensis is a promising aquaculture fish with sexual dimorphism that males grow 2–3 times faster than females. Therefore, all-male breeding could increase production of this fish, and sex-linked markers would be useful during the breeding process. In this study, a male-associated marker named PuGT54 was isolated in P. ussuriensis from a previously constructed microsatellite library. A total of 185 P. ussuriensis individuals containing 95 females and 90 males were used to test the usage of this maker. And results showed that sexes of all individuals were successfully identified, indicating the high reliability and accuracy of this marker for sex identifi cation. Furthermore, the male-specifi c fragment amplifi ed by this maker was cloned and sequenced, which was 118 base pairs in length. As homologous genes of this fragment was not found through BLASTn, detailed information of the male-specifi c fragment is unknown presently. Nevertheless, this marker would be helpful in conservation, breeding and ecological study of P. ussuriensis.

Gene expression during different periods of the handling-stress response in Pampus argenteus

Common aquaculture practices subject fish to a variety of acute and chronic stressors. Such stressors are inherent in aquaculture production but can adversely affect survival, growth, immune response, reproductive capacity, and behavior. Understanding the biological mechanisms underlying stress responses helps with methods to alleviate the negative effects through better aquaculture practices, resulting in improved animal welfare and production efficiency. In the present study, transcriptome sequencing of liver and kidney was performed in silver pomfret( Pampus argenteus) subjected to handling stress versus controls. A total of 162.19 million clean reads were assembled to 30 339 unigenes. The quality of the assembly was high, with an N50 length of 2 472 bases. For function classification and pathway assignment, the unigenes were categorized into three GO(gene ontology) categories, twenty-six clusters of egg NOG(evolutionary genealogy of genes: non-supervised orthologous groups) function categories, and thirty-eight KEGG(Kyoto Encyclopedia of Genes and Genomes) pathways. Stress affected different functional groups of genes in the tissues studied. Differentially expressed genes were mainly involved in metabolic pathways(carbohydrate metabolism, lipid metabolism, amino-acid metabolism, uptake of cofactors and vitamins, and biosynthesis of other secondary metabolites), environmental information processing(signaling molecules and their interactions), organismal systems(endocrine system, digestive system), and disease(immune, neurodegenerative, endocrine and metabolic diseases). This is the first reported analysis of genome-wide transcriptome in P. argenteus, and the findings expand our understanding of the silver pomfret genome and gene expression in association with stress. The results will be useful to future analyses of functional genes and studies of healthy artificial breeding in P. argenteus and other related fish species.

Edible Peanut Worm(Sipunculus nudus) in the Beibu Gulf： Resource, Aquaculture, Ecological Impact and Counterplan

Sipunculus nudus is an important economic species because of its high nutritional and medicinal values. The exploitation and utilization of S. nudus primarily occur in the coastal regions of the Beibu Gulf. However, wild resource of S. nudus is rapidly decreasing because of the overexploitation, which has led to considerable developments of artificial breeding techniques. The cultivation scale of S. nudus has increased in response to successful artificial breeding; however, methods for culturing S. nudus in tidal flats or ponds require further study. Most studies have focused on the breeding, nutrition, medical value and ecological impact of these worms. Studies on the distribution, sediment requirements, nutrition characteristics, breeding techniques and aquaculture ecology of this species are summarized in this paper to promote the development of the aquaculture industry for S. nudus. The high biomass of S. nudus in the Beibu Gulf is positively correlated with the sediment characteristics and water quality of the region. The production of peanut worm has improved to some extent through culturing; however, the nutrient value and ecological environment problems have been observed, which reflect the over exploitation of trace elements and the sediment. These problems will worsen unless they are resolved, and the release of organic materials, nitrogen and phosphorus during harvesting impacts the coastal environment. Moreover, genetic erosion is a potential risk for larvae in artificial breeding programs in tidal flats. Therefore, culturing and collecting methods should be improved and the wild resource conservation should be implemented to promote the sustainable development of the peanut worm.

The metabolite profiling of coastal coccolithophorid species Pleurochrysis carterae(Haptophyta)

Pleurochrysis carterae is a calcifi ed coccolithophorid species that usually blooms in the coastal area and causes aquaculture losses. The cellular calcifi cation, blooming and many other critical species specifi c eco-physiological processes are closely related to various metabolic pathways. The purpose of this study is to apply the unbiased and non-destructive method of nuclear magnetic resonance(NMR) to detect the unknown holistic metabolite of P. carterae. The results show that NMR spectroscopic method is practical in the analysis of metabolites of phytoplankton. The metabolome of P. carterae was dominated by 26 metabolites involved in a number of dif ferent primary and secondary metabolic pathways. Organic acids and their derivatives, amino acids, sugars, nucleic aides were mainly detected. The abundant metabolites are that closely related to the process of cellular osmotic adjustment, which possibly refl ect the active ability of P. carterae to adapt to the versatile coastal niche. DMSP(dimethylsulphoniopropionate) was the most dominant metabolite in P. carterae, up to 2.065±0.278 mg/g lyophilized cells, followed by glutamate and lactose, the contents were 0.349±0.035 and 0.301±0.073 mg/g lyophilized cells respectively. Other metabolites that had the content ranged between 0.1–0.2 mg/g lyophilized cells were alanine, isethionate and arabinose. Amino acid(valine, phenylalanine, isoleucine, tyrosine), organic acid salts(lactate, succinate), scyllitol and uracil had content ranged from 0.01 to below 0.1 mg/g lyophilized cells. Trigonelline, fumarate and formate were detected in very low content(only thousandths of 1 mg per gram of lyophilized cells or below). Our results of the holistic metabolites of P. carterae are the basic references for the further studies when multiple problems will be addressed to this notorious blooming calcifying species.