中国对虾(Fenneropenaeus chinensis)“黄海3号”新品种的培育

2006年收集中国对虾“黄海1号”保种群以及海州湾、莱州湾2个野生群体为基础群体构建核心育种群,采用群体选育技术以仔虾Ⅰ期耐氨氮胁迫成活率和收获时对虾体重为选育指标,经过连续5代选育,培育出中国对虾“黄海3号”新品种。新品种耐氨氮胁迫能力强,仔虾Ⅰ期成活率较商品苗种提高21.2%,养殖成活率提高15.2%;生长速度快,收获对虾平均体重较商品苗种提高11.8%。AFLP技术分析获得5代选育群体的平均多态位点比例分别为42.28%、40.64%、40.32%、39.95%和38.05%。研究结果显示,随着选育世代的增加,选育群体的遗传多样性呈现下降趋势,但随着选育时间的延长,世代之间的分化逐渐降低,群体的遗传结构开始趋于稳定。     

三疣梭子蟹新品种“黄选1号”的选育

2005年收集鸭绿江口、莱州湾、海州湾、舟山4个三疣梭子蟹野生地理群体,构建核心育种群体,评估有效群体含量,制定合理保种模式;在5％留种率下,采用群体选育方法进行新品种培育.到2010年经过连续5个世代选育,形成特征明显、性状稳定的三疣梭子蟹新品种“黄选1号”.在相同养殖条件下与商品苗种进行对比测试.“黄选1号”收获时平均个体体重提高20.12％,成活率提高32.00％,全甲宽变异系数小于5％“黄选1号”新品种2010～2012年进行中试养殖200余hm2,养殖方法以“蟹、虾、贝、鱼”多品种生态养殖为主.结果显示,新品种收获时个体规格大、成活率高、整齐度好,平均单产提高30％;已推广到山东、河北及浙江等地,累计养殖面积6 000余hm2,获得较显著的经济效益和社会效益.     

中国对虾“黄海2号”新品种的培育

选取中国对虾“黄海1号”、“即抗98”2个养殖群体,朝鲜半岛南海群体、乳山湾群体、青岛沿岸群体及海州湾群体等4个自然群体,采用不平衡巢式交配方案设计,于2005年建立了中国对虾育种的基础群体。设计并建立了中国对虾的多性状复合育种技术,选育的目标性状为生长速度、白斑综合症病毒感染后的存活时间及养殖存活率。为最大限度消除环境差异对遗传方差的影响,在中国对虾家系构建过程中采用标准化程序培育苗种,经过对体长为3cm左右的幼虾进行荧光标记,每个家系标记后混合养殖测试。随机从每个家系中抽取同等数目的标记对虾分成2组,一组共同养殖在养殖池中,测试生长速度和养殖存活率,另一组在封闭的水泥池中进行WSSV感染实验,测试病毒感染后的存活时间长短。中国对虾遗传参数的估计结果表明,养殖170天收获体重的遗传力为0.22,抗WSSV存活时间的遗传力为0.14,存活率的遗传力为0.03。采用BLUP法估算个体育种值,通过百分比加权的形式,分别赋予生长速度、抗WSSV存活时间和存活率的加权值为：80%、15%和5%,并对性状育种值进行标准化,获得综合选择指数;按照每个家系及个体的综合选择指数大小进行家系间及家系内留种,并根据系谱信息,设计交配方案,将每代的近交系数控制在1%以内。选育4代后的统计结果表明,平均每代的遗传进展为：生长速度,13.56%;抗病力,6.76%;存活率,5.05%。三个性状中,收获体重的遗传力最高、加权最大,每代获得的遗传进展稳定在12%以上;抗WSSV存活时间与存活率遗传力较低,每代获得的遗传进展相对小且不稳定。实验培育的新品种“黄海2号”于2009年通过全国水产原良种委员会审定,可在适合中国对虾的养殖区进行推广养殖。为更快地培育抗病新品种,解决对虾养殖病害问题,进一步的研究需查明对虾抗病的遗传机制,提高抗病性状的选择强度,快速培育对虾抗病新品种。     

2014年全国渔业主导品种——虾

<正>A.中国对虾"黄海2号"品种来源:收集4个中国对虾自然群体及2个选育群体,由中国水产科学研究院黄海水产研究所选育。审定情况:2009年2月通过全国水产原种和良种审定委员会审定,获水产新品种证书。审定编号:品种登记号:GS01-002-2008。特征特性:生长速度快,收获体重比未经选育的野生种提高30%以上,适     

凡纳滨对虾“海兴农2号”

<正>针对当前对生长速度快、抗逆性强的凡纳滨对虾新品种需求量不断提高,广东海兴农集团有限公司、广东海大集团股份有限公司、中山大学、中国水产科学研究院黄海水产研究所联合选育出新品种凡纳滨对虾"海兴农2号"(品种登记号:GS-01-004-2016)。该品种利用从美国夏威夷、佛罗里达、关岛和新加坡等地区引进的8个亲虾群体,以生长和成活率为选育目标,采用BLUP技术经连续5代选育而成。     

凡纳滨对虾“中科1号”

凡纳滨对虾“中科1号”（品种登记号：GS-01-007-2010）,是以从美国夏威夷、佛罗里达州引进的2个群体和国内5个养殖群体为基础群体,以生长速度和仔虾淡水应激成活率为主要选育指标,经2代群体选育及5代家系选育获得的品种。     

河北省开展中国对虾“黄海5号”新品种养殖示范

正中国对虾"黄海5号"新品种(GS—01—002—2008),是黄海水产研究所在中国对虾"黄海2号"和野生群体基础上采用多性状复合育种技术,经6代选育而成。在相同养殖条件下,与未经选育的中国对虾相比,白斑综合征病毒抗性平均提高30.1%,生长速度提高26.5%。该品种是农业部2018年主推品种之一。2018年,河北省农业产业技术体系特色海产品创新     

2个凡纳滨对虾群体仔虾的生长比较

以凡纳滨对虾二代群体自交、选育家系(♀)×引进SPF(♂)群体杂交,通过自然交配和人工培育获得2个仔虾群体,待仔虾长至体长0.8～1.0 cm时,随机选取60万尾放养于3口0.133 hm2的对虾养殖高位塘中,密度150万尾/hm2,其中二代仔虾2口塘,杂交仔虾1口塘.投喂"恒兴"牌饲料,相同的养殖环境和管理措施,养殖30 d后,每隔10 d进行一次生长测定.结果表明,杂交仔虾的生长速度和成活率高于二代仔虾,体质量和体长的总生长率高于二代仔虾,抗应激能力强于二代仔虾,较二代仔虾均匀;在40 d的观测期内杂交仔虾体长的绝对增长量为4.49 cm,二代仔虾为3.66 cm,提高22.68%,杂交仔虾体质量的绝对增长量为3.73 g,二代仔虾为2.20 g,提高69.55%,杂交仔虾生长优势明显.     

凡纳滨对虾“正金阳1号”

正一、品种名称凡纳滨对虾"正金阳1号"二、品种来源凡纳滨对虾"正金阳1号"养殖新品种是以3个引进的凡纳滨对虾群体和凡纳滨对虾"中科1号"种虾为基础群体,以耐低温、耐低盐、生长速度和成活率为目标性状,采用家系选育和品系选育相结合的选择育种技术,经连续4代选育获得的凡纳滨对虾选育品种。三、审定情况2017年通过全国水产原种和良种审定委员会审定。审定编号为GS-01-006-2017。     

凡纳滨对虾群体杂交与自交 F1低溶氧与高氨氮耐受性比较

利用6个遗传背景不同的凡纳滨对虾(Litopenaeus vannamei)群体,通过群体间自交与杂交建立了8个交配组合。对不同交配组合F1,在幼虾和成虾阶段,进行低溶氧与高氨氮48 h胁迫试验,比较不同交配组合群体在不同生长阶段的高氨氮与低溶氧耐受性。结果显示,低溶氧胁迫,YH♀×ZX♂、SS♀×SS♂、HD♀×YH♂交配组合幼虾存活率分别为76.23%、74.61%、74.38%,显著高于其他交配组合存活率(P0.05),成虾的存活率分别为83.08%、65.57%、71.12%,可作为耐低溶氧优良品系选育的候选材料;高氨氮胁迫,YH♀×KN♂、HD♀×YH♂、YH♀×ZK♂交配组合幼虾存活率分别为97.71%、86.43%、80.01%,显著高于其他交配组合(P0.05),成虾存活率分别为85.53%、74.18%、69.23%,可作为耐高氨氮优良品系选育的候选材料;HD♀×YH♂交配组合低溶氧与氨氮耐受性均较好,但不同交配组合低溶氧与氨氮耐受性间相关性检验不显著(P0.05)。研究发现,亲本中雌虾来源为YH,子代低溶氧耐受性优良,推断抗低溶氧性状为母系主导遗传;对虾低溶氧的耐受性随着生长发育的进行而降低,高氨氮耐受性随着生长发育的进行而增强;各交配组合高氨氮和低溶氧耐受性,在幼虾阶段和成虾阶段均呈极显著相关(P0.01),表明凡纳滨对虾低溶氧与高氨氮耐受性适宜在幼虾阶段进行遗传评估。     

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.     

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.     

Involvement of gonadal steroids in final oocyte maturation of white perch (Morone americana) and white bass (M. chrysops): in vivo and in vitro studies

Plasma estradiol-17 (E₂), testosterone (T), 17,20-dihydroxy-4-pregnen-3-one (DHP) and 17,20,21-tri-hydroxy-4-pregnen-3-one (20-S) levels were measured by radioimmunoassay (RIA) in white perch (Morone americana) and white bass (M. chrysops) that were induced to undergo final oocyte maturation (FOM) with human chorionic gonadotropin (hCG). Plasma DHP levels increased in females of both species in association with oocyte germinal vesicle migration (GVM) and germinal vesicle breakdown (GVBD) and decreased thereafter. Plasma 20-S levels also increased with oocyte GVM in white bass, but were several-fold lower than DHP levels. Circulating E₂ and T levels were greatest during GVM and GVBD in both species and decreased to low levels during oocyte hydration and ovulation. Follicles from white perch and white bass which received a priming injection of hCG in vivo, produced both DHP and 20-S in vitro after exposure to hCG and their oocytes underwent GVBD. Ovarian incubates from unprimed fish of either species produced only E₂ and T and their oocytes did not complete GVBD. Oocytes from unprimed bass, but not perch, matured when follicles were exposed to hCG in vitro. Both trilostane and cycloheximide blocked in vitro production of DHP and 20-S and oocyte GVBD by white perch follices. DHP and 20-S were equipotent inducers of FOM in the GVBD bioassay. None of several other structurally-related steroids tested were effective within a physiological range of concentrations. These results indicate a role for DHP and 20-S in the control of FOM in white perch and white bass.     

Cardiac,ventilatory and metabolic responses of two ecologically dissimilar species of fish to waterborne cyanide

Changes in heart rate, ventilatory activity and oxygen consumption were determined in trout (Salmo gairdneri) and brown bullhead catfish (Ictalurus nebulosus) during exposure to a steadily increasing concentration of waterborne cyanide selected to produce death in 8–9 hours for each species. The lethal cyanide concentration for the bullheads was an order of magnitude higher than for trout. Trout developed an immediate and gradually increasing bradycardia throughout the exposure period. Cyanide produced tachycardia in the bullhead followed by a gradual onset of bradycardia as the concentration of cyanide was raised. Pericardial injection of atropine (a muscarinic cholinergic antagonist) indicated that bradycardia in the trout was due initially to increased vagal tone but later due to the direct effect of cyanide on the heart. Hyperventilation in the trout persisted throughout the exposure period, although the rate and amplitude fluctuated and was variable between individual fish. During the last hour of exposure (highest cyanide concentration), ventilation was characterized by rapid, shallow breaths followed by a sudden respiratory arrest. The bullheads exhibited hyperventilation during the first 3 hours of exposure followed by a gradual, linear drop in ventilation rate and amplitude until death occurred. Cardiac and ventilatory responses in both species were attributed to stimulation of central and peripheral chemoreceptors by cyanide. Evidence is presented which suggests the initial response in the bullheads was due, at least in part, to gustatory stimulation by the cyanide. Oxygen consumption of the trout remained above pre-exposure levels for the majority of the test period. Oxygen consumption in the bullhead paralleled the changes in heart and ventilatory rates. Whole-body lactate levels of fingerlings of both species during cyanide exposure were measured to estimate the extent of anaerobiosis. Whole-body lactate levels were much greater in the bullheads than the trout, indicating a higher capacity for anaerobiosis, possibly due to a greater fuel supply. Overall, the trout responded to cyanide in a manner similar to that produced by environmental hypoxia whereas the bullheads experienced a gustatory stimulus which masked the hypoxia-like response.     

An overview of stress physiology of fish transport: changes in water quality as a function of transport duration

This study brings an integrated analysis about the relationship between water deterioration and its physiological consequences in live fish transport. The analysis was focused on the transport water and its deterioration, and physiological challenges imposed on the fish. Usual commercial handling procedures employed to mitigate fish stress during transport were discussed. Future topics of research for the establishment of safer fish transport protocols were proposed. Transport was classified into short (≤8 h) or long transport (>8 h). The main issue in short transports should be the prevention of water pH reduction, while in long transports it is the increase in ammonia. Plasma cortisol is the most employed marker for stress and is acutely elevated upon short episodes of transport, but remains elevated even in long‐transport events. Plasma glucose is perhaps a better marker for handling stress. Plasma lactate, pH, osmolality CO₂ and ions should be more often evaluated. Plasma Na⁺ and Cl^‐ are very useful markers of acidosis, due to their respective exchange for H⁺ and , for acid–base regulation. The establishment of species‐specific transport protocols should be preceded by such combined analyses of water and physiological parameters.     

Are hatchery‐reared abalone naïve of predators? Comparing the behaviours of wild and hatchery‐reared northern abalone,Haliotis kamtschatkana (Jonas, 1845)

Abalone populations have declined worldwide, generating interest in enhancement using hatchery‐reared individuals. In many cases, such restoration efforts have met with limited success due to high predator‐induced mortality rates. Furthermore, the mortality rates of outplanted hatchery abalone are often considerably higher than for wild individuals. This study uses northern abalone (Haliotis kamtschatkana) as a case study to determine whether hatchery‐reared abalone behave differently than their wild counterparts. In the field, outplanted hatchery‐reared abalone were significantly less responsive than wild abalone, in terms of number of abalone responding and intensity of response, to nearby movement and to physical contact with an inert probe. Also, when encountering a cue to which all abalone responded (a seastar predator), hatchery‐reared individuals remained subdued. Anti‐predator behavioural deficits in hatchery‐reared abalone were more pronounced in 4‐year‐old individuals than in 1‐year‐old individuals, suggesting an influence of either age or amount of time spent in the hatchery environment. These behavioural differences are expected to increase the vulnerability of hatchery‐reared abalone to predators, and are likely a major cause of their elevated predator‐induced mortality when outplanted.     

Effects of cadmium on the kinetics of calcium uptake in developing tilapia larvae, Oreochromis mossambicus

The toxic effects of Cd²⁺ on Ca²⁺ influx kinetics in developing tilapia (Oreochromis mossambicus) larvae were evaluated. Addition of 20 µg l^-1 of Cd²⁺ to the environment of 0 and 3 day-old larvae competitively inhibited the Ca²⁺ uptake within 4h resulting in a great increase in K_m values for Ca²⁺ influx (19.3 and 17.4 fold, respectively) as compared with their respective controls. Consequently, the actual Ca²⁺ influx of larvae in solutions of 0.2 mM Ca²⁺ are suppressed by 32–45%. Also, 3 day-old larvae were more sensitive to internally accumulated Cd²⁺ than 0 day-old larvae. Although the Ca²⁺ influx in 0 and 3 day-old larvae may be restored to the levels of their respective controls with 24h of being transferred to a 20 µg l^-1 Cd²⁺ solution, total body Ca²⁺ content was significantly reduced in 3 day-old larvae. Increased Ca²⁺ uptake efficiency ensures sufficient Ca²⁺ for normal growth. However, rapid increase in Ca²⁺ influx after hatching also leads to higher Cd²⁺ uptake. Exposure to Cd²⁺ will lead to a drop in body Ca²⁺ content resulting in retardation of larval growth. Therefore, we conclude that if Ca²⁺ uptake is interfered with at this critical stage of development, larvae will not be able to maintain normal levels of body Ca²⁺ and will show signs of Cd²⁺ poisoning.     

Migratory dynamics of stream-spawning longnose gar (Lepisosteus osseus)

Abstract– Literature evidence suggests that lake-dwelling longnose gar (Lepisosteus osseus) enter tributary streams to spawn, Until the present study, the dynamics of this breeding migration had never been investigated quantitatively. During the summers of 1991 and 1992, longnose gar were captured as they entered Weaubleau Creek, Missouri, a tributary of Harry S. Truman Reservoir. The in-stream spawning migration began in early April and ended in late May, and was positively correlated with stream flow and water level, and negatively correlated with water temperature. In-stream residence times ranged from 15 to 94 days, with males exhibiting longer residence times than females. Once in-stream, longnose gar travelled as far as 10 km upstream and occupied certain pools at greater relative frequencies. Although the reason for this preferential utilization is not completely understood, it may relate to pool depth and riffle proximity. Longnose gar disperse from the spawning stream great distances, with gar captured in Weaubleau Creek being recaptured up to 48 km away. This information should provide fisheries biologists the means to consider the reproductive ecology of this species in their conservation and management decisions.     

Nutritional regulation of hepatocyte fatty acid desaturation and polyunsaturated fatty acid composition in zebrafish (Danio rerio) and tilapia (Oreochromis niloticus)

The desaturation and elongation of [1-¹⁴C]18:3n-3 was investigated in hepatocytes of the tropical warm freshwater species, zebrafish (Danio rerio) and Nile tilapia (Oreochromis niloticus). The hepatocyte fatty acid desaturation/elongation pathway was assayed before and after the fish were fed two experimental diets, a control diet containing fish oil (FO) and a diet containing vegetable oil (VO; a blend of olive, linseed and high oleic acid sunflower oils) for 10 weeks. The VO diet was formulated to provide 1% each of 18:2n-6 and 18:3n-3, and so satisfy the possible EFA requirements of zebrafish and tilapia. At the end of the dietary trial, the lipid and fatty acid composition was determined in whole zebrafish, and liver, white muscle and brain of tilapia. Both zebrafish and tilapia expressed a hepatocyte fatty acid desaturation/elongation pattern consistent with them being freshwater and planktonivorous fish. The data also showed that hepatic fatty acid desaturation/elongation was nutritionally regulated with the activities being higher in fish fed the VO diet compared to fish fed the FO diet. In zebrafish, the main effect of the VO diet was increased fatty acid Δ6 desaturase activity resulting in the production of significantly more 18:4n-3 compared to fish fed the FO diet. In tilapia, all activities in the pathway were greater in fish fed the VO diet resulting in increased amounts of all fatty acids in the pathway, but primarily eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3). However, the fatty acid compositional data indicated that despite increased activity, desaturation of 18:3n-3 was insufficient to maintain tissue proportions of EPA and DHA in fish fed the VO diet at the same level as in fish fed the FO diet. Practically, these results indicate that manipulation of tilapia diets in commercial culture in response to the declining global fish oil market would have important consequences for fish fatty acid composition and the health of consumers. Scientifically, zebrafish and tilapia, both the subject of active genome mapping projects, could be useful models for studies of lipid and fatty acid metabolism at a molecular biological and genetic level. This revised version was published online in August 2006 with corrections to the Cover Date.     

Production of diatom–bacteria biofilm isolated from Seriola lalandi cultures for aquaculture application

Controlled incorporation of selected microalgae and bacteria in aquaculture systems can be beneficial because they can act as microbiological control. That is why the characteristics of biofilm generated naturally in Seriola lalandi culture cages were analysed, their potential benefit to the growth of larvae was studied, and their controlled use for improving the larval viability and as a vector to improve incorporation of previously studied probiotic bacteria was tested. According to biodiversity results, these biofilms are composed of a diatom–bacteria mix showing a decrease in biodiversity in laboratory culture conditions being dominated by Navicula phyllepta and bacteria of the family Rhodobacteraceae. This can be produced on mesh substrates incorporated in bioreactors with rapid growth rate and adhesiveness. Preliminary results from the addition of substrates with this specific biofilm in larvae culture systems showed that it is consumed by the larvae without negative effects, while positive effects on the viability of larvae in combination with probiotics were observed. Considering preliminary results, the addition of these specific substrates with diatom–bacteria biofilms could be a good improvement for aquaculture systems and together with the use of probiotics can contribute to maintaining a stable and controlled system improving the viability of the larval fish culture in its early stages.