全基因组选择育种策略及在水产动物育种中的应用前景

全基因组选择的概念自2001年由Meuwissen等提出后便引起了动物育种工作者的广泛关注.目前,澳大利亚、新西兰、荷兰、美国的研究小组已经应用该方法进行了优质种牛的选择育种,并取得了很好的效果.此外在鸡和猪的选择育种中也有该方法的应用,但在水产动物选育中尚未见该方法使用的报道.本文对“全基因组选择育种”的概念和提出背景进行了归纳,对全基因组选择育种的优势进行了阐述,并详细介绍了其具体的策略,总结了目前全基因组育种所广泛采用的方法以及取得的成果,旨在为该方法在水产动物育种方面的应用研究提供科学参考.     

Geographical information system (GIS) environmental models for aquaculture development in Sinaloa State,Mexico

This paper describes the use of a geographical information system (GIS) to construct environmental models for land-based aquaculture development in the State of Sinaloa, Mexico. Based on the source data, submodels were created focusing on three different themes: general environmental issues, water resources and water quality. Models enabled multicriteria and multiobjective decision making concerning site selection and location. In assessing site considerations these general models identified wider resource management options and solved conflicts of land allocation and land use between aquaculture and agriculture. Smaller-scale, more specific models enabled more detailed studies on environmental issues.     

Predicting use of habitat patches by spawning horseshoe crabs (Limulus polyphemus) along a complex coastline with field surveys and geospatial analyses

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Inhibition of hirame rhabdovirus growth by RNA aptamers

RNA aptamers are artificial nucleic acids that specifically bind to a wide variety of targets. They are an effective tool for pharmaceutical research and development of antiviral agents. Here, we describe four Hirame rhabdovirus (HIRRV)‐RNA aptamers (H1, H2, H3 and H4) that we obtained from an in vitro process called the systematic evolution of ligands by exponential enrichment (SELEX). The HIRRV‐RNA aptamers specifically bind to HIRRV. Hirame natural embryo (HINAE) cells treated with virus and the RNA aptamer showed a decrease in appearance of cytopathic effect when compared with control (treated only with virus). Rhodovulum sulfidophilum was transformed with genes for the RNA aptamers, and the aptamers were detected in the culture medium, indicating that they were secreted from the cells. Thus, the recombinant R. sulfidophilum might be a powerful tool for the prevention of HIRRV in aquaculture.     

九孔鲍选择群体F1的选择反应与现实遗传力估计

以中国九孔鲍（Haliotis diversicolor aquatili）养殖群体与日本野生群体杂交子二代为选育基础群体,采用群体选育方法进行九孔鲍的选择育种研究,以估计该养殖群体的选择反应与现实遗传力。截断选择壳长最大的10％个体作为选择组亲本（SS）,从基础群体中随机抽取相同数量的个体作为对照组亲本（sc）,选择强度为1．755,结果表明,选择组与对照组在卵径、受精率方面无显著的差别（P〉0．05）,但选择组在幼体附着率、幼体变态率、幼体成活率及稚贝早期生长方面与对照组相比表现出不同程度的生长优势（P〈0．05）,选择组50日龄的稚鲍成活率达到35．07％,显著大于对照组23．62％（P〈0．05）,40—270日龄的选择组壳长选择反应和现实遗传力变化范围分别为13．64％～81．88％和0．21～0．53,平均为31．63％和0．36,选择组平均壳长显著大于对照组（P〈0．01）。研究初步显示,养殖群体的选择反应极显著,群体选育是养殖九孔鲍遗传改良的有效途径。     

Optimising codend configuration in a multispecies demersal trawl fishery

Abstract The relative efficiencies and selectivities of conventional and modified codends were examined in a demersal trawl fishery targeting several species, including eastern king prawns, Penaeus plebejus (Hess), whiting, Sillago spp. and cephalopods. The modifications to codends included: (i) reducing the circumference; (ii) increasing the mesh size in conventional diamond‐mesh designs; and (iii) orientating meshes on the bar so that they were square shaped. The codends were tested against a fine‐meshed control in paired comparisons onboard three commercial trawlers. The conventional codend comprised 41‐mm diamond‐shaped mesh attached to an anterior extension section at a ratio of 150 to 100 meshes and was demonstrated to be non‐selective for the targeted species. Reducing codend circumference to 100 meshes and increasing the size of mesh to 45 mm both improved selection for eastern king prawns, but the lateral mesh openings were estimated to be insufficient to allow juveniles of the other key species to escape. By contrast, codends made from 35‐ and 41‐mm mesh hung on the bar improved the size selection for eastern king prawns and selected stout whiting, Sillago robusta (Stead) (the smallest commercial‐sized fish) across narrow selection ranges and at 50% sizes of retention (L₅₀s) that were closely correlated to the transverse morphology of fish and the maximum mesh opening. With the exception of a reduction in catches of octopus, Octopus spp., by the 41‐square codend, there were no other impacts on commercial catches by the square‐mesh designs. It was concluded that diamond‐mesh codends are inappropriate for use throughout this multispecies fishery and that a modified design comprising at least 35‐mm mesh hung on the bar is required to minimise the fishing mortality of unwanted sizes of the key target species. The results are discussed in terms of the utility of these types of modifications for closely regulating selection in penaeid‐shrimp trawls.     

Spatial association between northern fur seal (Callorhinus ursinus) and potential prey distribution during the wintering period in the northern Sea of Japan

Elucidating the response of marine predators to oceanographic features helps in understanding their foraging strategies and the cause of their spatial overlap and interference with fishery activities. Northern fur seal is a highly pelagic species during the wintering period. In recent years, fur seals have consistently been found distributed near the coast of southwest Hokkaido, Japan. Because interference by fur seals with coastal fishery activities has become a serious concern, an understanding is sought as to why fur seals come ashore in this area. We conducted ship‐based observations and estimated fur seal density. To elucidate the spatial and seasonal association of fur seal distribution and ocean environments, we constructed statistical models to describe how potential prey distribution and oceanographic features influenced the fur seal spatial distribution during the wintering period. Fur seal distribution corresponded markedly to potential prey distribution, and they tended to aggregate along the narrow continental shelf that is the main geographic feature of this area, which is 2000 m deep and approximately 10 km from the coast. Walleye pollock [Gadus chαlcogrαmmα (Theragra chαlcogrαmmα)] and arabesque greenling (Pleurogrammus azonus), which are one of the main prey for fur seals, move to the shallow area to spawn on the continental shelf seasonally, so potential prey abundance could be higher in coastal areas than offshore. Moreover, the absence of a mesopelagic biotic community may be one of the main factors in the coastal distribution of the fur seal.     

Comparison of food selection and growth performance of koi carp, Cyprinus carpio L., and goldfish, Carassius auratus (L.) in mono- and polyculture rearing in tropical ponds

To compare the effect of polyculture against conventional monoculture on ornamental carp production, investigations on food selection and growth performance of koi carp (K), Cyprinus carpio L. and goldfish (G), Carassius auratus (L.) were conducted in a 11‐week rearing experiment in two monoculture (100% K and 100% G) and five polyculture (90% K–10% G, 70% K–30% G, 50% K–50% G, 30% K–70% G and 10% K–90% G) conditions in tropical ponds. There were three replicates for each treatment. Environmental conditions and food availability were similar in all the treatments. Ivlev's electivity index showed that both fish species avoided phytoplankton and preferred cladocerans to other zooplankton groups (copepods and rotifers) in monotypic conditions. However, in the polyculture treatments, the positive electivity of goldfish towards cladocerans reduced significantly (P<0.05), while the percentage of copepods, rotifers and phytoplankton in the gut content increased. No significant differences in weight gain, specific growth rate and deformities were recorded at harvest for koi carp between the different treatments (P>0.05). Even the survival rate of koi carp recorded above 90% in all the treatments. However, the goldfish recorded significantly better weight gain, specific growth rate and survival in monoculture (100% G), compared with the polyculture treatments (P<0.05). Goldfish deformities were lowest (P<0.05) in the monoculture treatment (2.42%). The number of marketable fish above a set size limit of 4 g total weight was significantly higher in the two monoculture treatments, compared with the five polyculture treatments (P<0.05). Keeping in view of the dietary similarities of koi carp and goldfish, and the aggressive nature of koi carp in polyculture, it is suggested to refrain from polyculture of goldfish and koi carp until further documentations relating to optimum stocking density and management of polyculture of ornamental carps are available.     

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。     

黄渤海夏季微藻调查

根据2011年夏季在黄渤海的采样调查分析了该海域网采浮游微藻的多样性,并从71个站位的采水样品与12个站位的拖网样品中分离了大量可培养的藻种。调查区拖网样品中共发现浮游微藻4门30属44种藻,以硅藻门(Bacillariophytas)为主,甲藻门(Dinophytas)次之。在实验室内利用毛细管法、平板法和稀释法分离纯化获得92株可培养微藻,经分子学鉴定为19种,包括9种硅藻、3种褐藻、3种不等鞭毛藻、2种绿藻、1种甲藻、1种定鞭藻。这些可培养微藻个体较小,多为微微型藻类和微型藻类,其中伪菱形藻(Pseudonitzschia sp.)和舟形藻(Navicula sp.)既能在固定样品中观察到,又能在实验室培养。圆筛藻(Coscinodiscus sp.)、梭角藻(Ceratium fusus)和夜光藻(Noctiluca scintillans)等小型藻类虽然在固定样品中所占比例较大,但是难以培养。此外,本次调查还首次在中国海域发现了Pseudobodo tremulans。黄渤海藻株的鉴定与培养不仅补充了中国微藻种质资源,还为促进微藻的研究和开发利用提供了重要材料。