An ecosystem-based assessment of the Korean blue crab trammel net fishery in the Yellow Sea and management implications

Landings in the blue crab, Portunus trituberculatus, fishery in Korean waters of the Yellow Sea have declined substantially from 11,000 t in the 1980s to 2,300 t in 2004. Blue crab habitat quality in the Yellow Sea has been degraded by anthropogenic activities including sand mining, land reclamation, and coastal pollution. Various traditional management measures have been implemented, including closed seasons during spawning and size limits, but these measures alone have been unsuccessful to conserve blue crab stocks. Consequently, a total allowable catch and a stock-rebuilding program using an ecosystem-based management approach were implemented in 2003 and 2006, respectively to rebuild blue crab stocks and restore habitats. This program involved assessment of both blue crab stock status and trammel-net fishery impacts at an ecosystem-level using an ecosystem-based fisheries assessment method ( [Zhang et al., 2009] and [Zhang et al., 2010]), which considered fishery data from catch and effort time-series, crab population biology, and ecosystem characteristics, including habitats and environmental conditions. Recent (2008) management status indices have shown significant positive change compared to conditions in 2000 with respect to sustainability of the stock and fishery and with regards to biodiversity and ecosystem habitat quality.     

Effects of fish meal replacement by low‐gossypol cottonseed meal on growth performance,digestive enzyme activity,intestine histology and inflammatory gene expression of silver sillago (Sillago sihama Forsskál) (1775)

A 56‐day feeding trial was conducted to evaluate the effects on the growth performance, digestive enzyme activity, inflammatory genes expression and intestine histology of silver sillago, Sillago sihama (Forsskål 1775), by replacing fish meal (FM) with low‐gossypol cottonseed meal (LCSM). Five isonitrogenous and isolipidic diets were formulated, including R0 group (control, containing 550.0 g/kg FM), R16 group (88.5 g/kg LCSM and 461.5 g/kg FM), R32 group (177.0 g/kg LCSM and 373.0 g/kg FM), R48 group (265.5 g/kg LCSM and 284.5 g/kg FM) and R64 group (354.0 g/kg LCSM and 196.0 g/kg FM). Fish fed R0 and R16 groups had a significantly higher weight gain rate (WGR) and specific growth rate (SGR) than R48 and R64 groups (p < .05). In contrast to whole‐body crude protein, whole‐body moisture increased with the FM level of substitution (p < .05). With the increased amount of LCSM in the diet, the activity of intestinal amylase (AMS) increased significantly (p < .05), and intestinal trypsin (TRP) decreased (p < .05). Dietary LCSM substitution upregulated the expression of intestinal tumour necrosis factor‐α (TNF‐α), the nuclear factor kappa‐light‐chain‐enhancer of activated B cells (NF‐κB), and interleukin one beta (IL‐1β), but downregulated tight junction proteins ZO‐1(ZO‐1), transforming growth factor beta‐3 (TGF‐β3) and interleukin 10 (IL‐10) expression. Histological analysis revealed progressive morphological damage to the mid‐intestine with higher levels of FM replacement. These results showed that 88.5 g/kg (16%) of FM replaced by LCSM with amino acids (methionine and lysine) supplementation did not significantly reduce growth compared with FM‐based control.     

Effects of antimicrobial peptides on growth,feed utilization,serum biochemical indices and disease resistance of juvenile shrimp,Litopenaeus vannamei

This experiment was conducted to assess the effects of antimicrobial peptides at different levels (Diet 1 (0%), Diet 2 (0.1%), Diet 3 (0.2%), Diet 4 (0.4%), Diet 5 (0.6%) and Diet 6 (1%)), on growth, serum biochemical indices and antioxidant effect, feed utilization and disease resistance in Litopeneaus vannamei. There were four replicates in each group in the experiment (mean weight = 0.21 ± 0.00 g) and also fed with their respective diets for 8 weeks. Growth performance compared with the control group (0%) significantly increased at first and then decreased among treatment groups (p < .05) whereas the survival rate ranged from 78% to 96%. No significant differences were observed in terms of moisture, crude protein and ash content, but there was a significant increase in crude lipid (p < .05). In serum, acid phosphatase, alkaline phosphatase, polyphenol oxidase, triglyceride, glucose and total cholesterol changed as compared with 0%. Total antioxidant capacity, glutathione peroxidase, catalase, superoxide dismutase and malondialdehyde were also different from 0%. Disease resistance was increased in shrimp among treatment groups with 0.4% recording the lowest mortality percentage of 37% after the challenge test. The results from the present study suggested that supplementation of AMP at 0.4% in shrimp diet can improve growth performance, antioxidants activities and innate immune response of Pacific whiteleg shrimp.     

‘无籽’瓯柑小孢子母细胞减数分裂特性基因RAD51和MS1的表达差异分析

‘无籽’瓯柑Citrus suavissima ‘Seedless’是野生型瓯柑Citrus suavissima的芽变,其花粉完全败育,败育起始于小孢子母细胞减数分裂形成四分体时期。研究‘无籽’瓯柑小孢子母细胞减数分裂异常的分子机制,有利于深入认识果树芽变的发生机制。随机选择“无籽”瓯柑和瓯柑各3株,根据花蕾直径采集花粉母细胞时期（Ⅰ）,四分体时期（Ⅱ）,单核花粉粒时期（Ⅲ）,双核花粉粒时期（Ⅳ）及花粉粒成熟期（Ⅴ）共5个时期的花蕾并分离花药,利用实时荧光定量聚合酶链式反应（qRT-PCR）分析减数分裂特性基因RAD51和MS1的相对表达量,3次重复。通过SPSS 16.0的最小显著差法（LSD）在0.01水平上进行各样品间的相对表达量差异分析。结果表明:RAD51和MS1基因的表达高峰均集中在第Ⅰ时期和第Ⅱ时期,且此时花药中的相对表达量均极显著（P<0.01）高于花蕾。第Ⅰ时期花药中,‘无籽’瓯柑RAD51的相对表达量为瓯柑的3.7倍,MS1可达300倍;但同时期花蕾中,RAD51的相对表达量仅1.1倍,MS1为140.0倍。‘无籽’瓯柑RAD51基因在第Ⅰ时期和第Ⅱ时期的相对表达量极显著（P<0.01）高于瓯柑,说明‘无籽’瓯柑小孢子母细胞和四分体时期的细胞内均存在DNA受损现象;‘无籽’瓯柑MS1基因在第Ⅰ时期的相对表达量极显著（P<0.01）高于瓯柑,但第Ⅱ时期极显著（P<0.01）低于瓯柑,推测‘无籽’瓯柑败育花粉的形成与MS1基因表达紊乱引起油脂分泌、转运异常密切相关。图6表1参24     

海藻糖在双歧杆菌冻干菌粉制备和保藏中生物保护作用的初探

对新型保护剂海藻糖在长双歧杆菌（Ｂｉｆｉｄｏｂａｃｔｒｅｒｉｕｍ ｌｎｇｕｍ）冻干菌粉制备和保藏中的生物保护作用进行了初步研究。结果表明：４种双糖保护剂中,涨藻糖的细胞冻干存活率分别是蔗糖的６倍和麦芽的４．５倍（Ｐ〈０．０１）,而且显著高于乳糖（Ｐ〈０．０５）;４种复合保护剂中添加海藻糖后,细胞冻干存活率均显著提高（Ｐ〈０．０１）;海藻糖还可明显改善冻干菌粉的细胞贮藏稳定性,延长活菌保藏期。     

Establishment and characterization of a continuous cell line (GF-1) derived from grouper, Epinephelus coioides (Hamilton): a cell line susceptible to grouper nervous necrosis virus (GNNV)

A new continuous cell line (GF-1) was established and characterized. The GF-1 cell line, derived from the fin tissue of a grouper, Epinephelus coioides (Hamilton), was maintained in L15 medium containing 5% foetal bovine serum (FBS) at 28 °C, and has been subcultured more than 160 times since 1995. The majority of GF-1 cells are fibroblast-like, together with some epithelioid cells. Spontaneous transformation of GF-1 cells occurred during subculture 50 to subculture 80, and led to an increase of plating efficiency, less requirement of FBS and de novo susceptibility to grouper nervous necrosis virus (GNNV). Cytopathic effects (CPEs) could be observed in GF-1 cells 3–5 days post-infection with pancreatic necrosis virus (IPNV), hard clam reovirus (HCRV), eel herpes virus Formosa (EHVF) and GNNV. In addition, abundant GNNV particles were found in the cytoplasm of GNNV-infected GF-1 cells using electron microscopy and nucleic acids of GNNV virus were detected by polymerase chain reaction in the culture medium of GNNV-infected cells after CPE appeared. The experimental results indicated that GF-1 can effectively proliferate fish nodavirus and is a promising tool for studying fish nodavirus.     

中国茶产业集群的特征及其发展

本文介绍了茶产业集群的概念和中国茶产业集群发展的特征。中国茶产业集群发展兼具阶段性;自发性形成和外生性形成机制并存;茶产业效应从第一产业向第二、第三产业快速辐射效应明显。笔者就进一步促进中国茶产业集群的发展,提出了需要进一步加强的支持体系。     

An immunohistochemical study of protein kinase C in the bovine retina

The expression of protein kinase C (PKC) was studied in the bovine retina by immunohistochemical analysis. Western blot analysis showed that PKC isoforms, including alpha, betaI, delta and theta, were detected in the bovine retina. By immunohistochemistry, both PKC alpha and betaI were expressed in all retinal layers, with an intense localization of both PKC alpha and betaI detected in bipolar cells in the inner nuclear cell layer and in some glial cells in ganglion cell layers. The immunoreactivity of both PKC delta and theta was quite weak in the retinal layers, compared with that of PKC alpha and betaI. These findings suggest that both conventional and novel PKCs are differentially expressed in the bovine retina.