我国海水养殖贝类病害发生现状及防控策略

贝类养殖是我国水产养殖业的重要组成部分，在促进经济社会发展、提高就业率、改善人民生活及保护生态环境等方面发挥了重要作用，其经济、社会和生态功能日益凸显。近年来，因环境胁迫和病原侵染引发的海水养殖贝类暴发性病害时有发生，所造成的经济损失巨大，严重阻碍了海水养殖产业的绿色高质量发展。贝类缺乏适应性免疫，且主要养殖于开放或半开放水体，难以通过疫苗注射或环境调控等手段进行病害防控。贯彻“绿色防控”的理念，加快病害预警预报体系建设是海水养殖贝类病害防控的重要发展方向。本文综述了我国海水贝类养殖及病害发生的现状，并结合团队前期研究和病害预警预报工作实践,提出了海水养殖贝类病害防控策略，以期提升我国水产动物疫病防控能力，为保障水产品稳定安全供给、促进水产养殖业绿色高质量发展提供参考。     

履带式滩涂贝类采收机设计与试验

针对环渤海地区滩涂贝类养殖产业贝类采收环节缺少机械化采收设备，人工采收贝类劳动强度大、作业效率低、作业环境泥泞等问题，设计了一款履带式滩涂贝类采收机。整机采用液压双联泵进行液压动力的分配，并通过液压系统仿真软件AMESim对整机液压动力系统进行仿真模拟；根据滩涂养殖贝类的生物特性、地质特点和作业需求，设计挖掘传送装置，采用固定式挖掘铲和振动筛进行贝泥沙混合物的挖掘与筛选，通过液压缸的伸缩调整采收机作业深度；基于各个机构和液压元件的分布，设计履带式底盘。通过实地试验，完成样机的性能测试。结果显示：试验地区采收机的最佳工艺参数为作业速度0.15 m/s,振动筛转速380 r/min,振动筛筛面倾角12°,可实现满足农艺要求的滩涂贝类无水化和浅水化机械化采收作业。研究表明，履带式滩涂贝类采收机具有较好的稳定性，且在提高工作效率、降低劳动强度等方面效果显著，具有较好的推广应用前景。     

浙江滩涂贝类种业科技创新发展及展望

我国拥有1 512 300 hm²沿海滩涂,而滩涂贝类是潮间带滩涂的优势种类,具有生长快、适应性强、环境友好等诸多优点,因此发展滩涂贝类养殖空间广阔、条件优越、潜力巨大。浙江滩涂贝类养殖历史悠久,在养殖技术与模式、人工采苗与育苗、大规格苗种培育、新品种培育等方面具有明显特色和优势,同时在种业科技创新与发展方面面临巨大挑战。本文综述了浙江滩涂贝类养殖产业、苗种生产技术、种质创新与良种创制的历史与现状,围绕经济性状精准测评、育种技术创新、优质抗逆新品种培育、高效扩繁关键技术和装备研发、种业体系建设等方面,提出了未来特别是“十四五”期间滩涂养殖贝类良种创制与种业发展的重点任务。     

深水网箱选址初步研究

为给深水网箱的合理选址提供参考，初步研究了网箱拟养海区需具备的环境条件、水质要求、网箱设施的安全性及养殖鱼类的适应性等。结果表明，深水网箱的选址应符合法律法规，以不破坏环境及其它产业的发展、同时又能取得较好效益为原则。在确定深水网箱养殖区域前，应进行海区初选、拟养海区的水文环境调查、当地的社会经济和生态调查，结合网箱类型和养殖品种，以网箱设施安全性、养殖鱼类适应性以及网箱养殖经济实用性和规划合理性等方面的综合论证为基础，分析拟养海区的利弊因素，综合平衡后确定养殖海区。     

贝类多倍体研究中部分问题的探讨

海洋贝类增养殖作为水产养殖的重要组成部分，在近几十年中发展迅速，但随着养殖面积和养殖密度的不断增加，近几年出现了严重制约产业发展的瓶颈问题，如单产降低、品质下降、大面积死亡等问题，其主要原因是贝类种质资源衰退、动物能量收支失窃，因而以改良贝类种质资源、改善动物能量收支平衡、提高贝类增养殖的产量为目的的贝类多倍体研究，已成为海洋生物技术发展中的一个热点，许多专家和学者都在这方面做了不少的工作。但随着研究的进一步深入，在该方面存在着的许多问题也变得越来越明显，对这些问题还需做一步的研究。     

我国滩涂增养殖业存在的问题与应对措施

1存在的问题1.1缺乏系统研究和沿岸带整体开发意识 我国海水增养殖业的发展,是在缺乏系统理论和技术研究的情况下,大规模启动的,特别是对虾养殖。因此无论是在布局上,还是在养殖模式方面,都缺乏养殖生态学理论和生态调控等技术的指导。如大规模发展中国对虾单一种类的养殖,一方面导致其产业滑坡,另一方面也严重破坏了大片滩涂的生态平衡。近年来,我国近海鱼类和滩涂埋栖性贝类资源的严重衰退,酷捕滥采     

重庆市名特优水产养殖现状及对策

我市名特优水产养殖在90年代取得较大发展，但总体上仍处于较低水平，制约因素主要有生产技术（苗种培育、饲料开发、疾病防治等）开发与推广滞后，资金短缺，基础设施落后；宏观调控力度弱；种质资源污染及产业化程度低等，我市发展名特优水产品生产在政策、技术、市场、地域、品种等方面具有优势，应采取加强宏观调控，积极开展苗种繁育、养殖方式、产品保鲜和加工等技术研究，强化种植资源管理，大力调整品种结构等措施。     

17β-HSDs的种类和功能概述及其在贝类中的研究进展

为深入解析17β-HSDs (17β-羟基类固醇脱氢酶)对贝类性腺发育和生殖内分泌的调控机制，本文综述了17β-HSDs的种类和功能，对迄今已报道的所有亚型进行了分类归纳，并对贝类等水产动物中17β-HSDs的克隆表达、功能阐述、机制推测进行了调研总结。目前，虽然17β-HSDs调控贝类生殖过程研究已取得一定的进展，但仍有很多重要的科学问题尚待解答，需要重点加强“发现贝类中17β-HSDs新亚型、分析时空表达特征、解析构效关系、明晰环境污染物的影响、制定相应对策、指导产业实践应用”等方面的研究。本综述结合了其他物种的成熟研究和最新成果，为深入探究17β-HSDs调控贝类性腺发育和生殖内分泌的机理及应用提供了借鉴。     

福建省抗风浪网箱养殖产业化问题刍议

本文分析了福建省抗风浪网箱养殖的发展现状及存在的问题，提出了积极、稳妥地推进我省近海抗风浪网箱养殖产业化的对策与措施。即：(1)政府对抗风浪网箱制造企业、养殖龙头企业及相关企业、养成品销售市场等方面继续给予资金和优惠政策扶持，加快已发展网箱的投产速度；(2)鼓励“强强企业联合”，建立抗风浪网箱养殖基地，积极推行“网箱基地 养殖户”和“订单渔业”的抗风浪网箱养殖经营模式；(3)加大科研投入，尽快完善重力型沉浮式抗风浪网箱的技术性能，并开展阻流设施、换网机械、鱼规格分级设备、自动投饵设备等配套设施的后续研究，加速产业化进程；(4)开展全省抗风浪网箱养殖规划研究。     

秦皇岛市贝类产业发展状况调研报告

为了解秦皇岛市贝类产业的发展状况,从不同角度对秦皇岛市的贝类产业进行了调查研究。从微观的角度,考察了养殖、加工、销售、技术服务机构的经营状况;从宏观的角度,考察了产业化经营组织以及各级政府对贝类产业发展所提供的政策支撑及其效果。根据调研结果,总结了秦皇岛市贝类产业在发展规模、产业集群、出口营销、政策支撑等方面具有突出优势,也分析了政府监管不到位、人才短缺、产品层次低、产业链发展不协调等问题,并针对问题提出了对策和建议。     

Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean

The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna.     

Rare serotype occurrence and PFGE genotypic diversity of Streptococcus agalactiae isolated from tilapia in China

Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China.     

Growth performance,digestive enzyme activity and immune response of Japanese sea bass,Lateolabrax japonicus fed with fructooligosaccharide

In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg.     

Evaluation of a Fast Method Based on the Presence of Two Restriction Sites in the Mitochondrial ND5 (mt ND5) Gene for the Identification of Scomber Species

The purpose of this work was to evaluate the suitability of a method based on the presence of two restriction sites (for Hae III and Hindf I) in the mitochondrial NADH dehydrogenase subunit 5 (mt ND5) gene to identify Scomber species. The evaluation was performed on 144 reference and market samples by sequencing of the entire 505-bp fragment of the mt ND5 gene and of a 464-bp fragment of the Kocher fragment of the cytochrome b gene (mt Cytb). Sequence analysis of any of the two fragments allows the identification of each of the four Scomber species, but S. japonicus and S. colias had the same restriction sites at the ND5 amplicon and would not have been differentiated by this analysis. Similarly, loss of the Hae III site in some S. scombrus individuals would have misidentified them as not being Scomber. All the market products were correctly labeled except one acquired in Spain labeled as originating in the Atlantic and containing S. japonicus.     

Growth hormone (GH) and reproduction: a review

Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations.     

Purification and partial characterization of GtHs (cfLH and cfFSH) from Indian walking catfish (Clarias batrachus) (L.) and development of a homologous ELISA for cfLH

Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL^?1 (1.25 ng well^?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation.     

Controlled infection of Poecilia reticulata Peters (guppy) with Tetrahymena by immersion and intraperitoneal injection

Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg^?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality).