智利外海茎柔鱼资源密度分布与渔场环境的关系

根据2006年4-6月我国鱿钓船对东南太平洋智利外海茎柔鱼探捕所获资料,采用效能比方法,对茎柔鱼资源密度指标CPUE值进行了估算.分析表明,整个探捕海域均有茎柔鱼分布,且资源密度较高,但不同区域资源密度有所差异.南部区域(78°30'～84°W,37°30'～41°S),CPUE范围为0.4～10.3尾/线·h,平均2.8尾/线·h,高CPUE(5.0尾/线·h以上)区域分布在79°～79°30'W、40°～40°30'S附近.北部区域(76°～78°W,28°～30°S),CPUE范围为1.0～5.6尾/线·h,平均3.1尾/线·h,高CPUE(5.0尾/线·h以上)区域分布在28°30'S、77°W附近.南部和北部区域的温盐结构差异显著,南部区域各层的水温和盐度均低于北部区域相应水层.经分析,南部区域CPUE与上层(25～75 m)水温和深水层(300～325 m)盐度的关系较为密切,北部区域CPUE与深层水温(150～250 m)和盐度的关系较为密切.     

长牡蛎二倍体和三倍体外套膜的差异

本文从外观、组织切片、蛋白质和糖元含量等方面分析了长特蛎二倍体和三倍体外套膜的差异。与二倍体相比,三倍体外套膜厚、不透明、呈乳白色、结弱组织较厚,糖原含量高３．９倍。     

山东沿海褶牡蛎与太平洋牡蛎等位基因酶的遗传变异

采用水平淀粉凝胶电泳技术研究了山东沿海莱州 (LZ)、俚岛 (LD)和青岛 (QD)三地褶牡蛎自然群体以及荣成的太平洋牡蛎 (TP)养殖群体的等位基因酶遗传变异。进行测试的 9种酶中共检测到 2 0个位点。LZ与QD群体的多态位点比例为 6 0 .0 % ,其余两群体均为 5 5 .0 %。LZ、LD、TP和QD各位点平均有效等位基因数分别为 1.42 2± 0 .16 5、1.2 38± 0 .0 85、1.2 0 7± 0 .0 86和 1.32 6± 0 .119。平均杂合度观察值分别为 0 .2 16± 0 .0 5 0、0 .16 5± 0 .0 36、0 .139± 0 .0 34和 0 .195± 0 .0 42。结果表明 ,LZ和QD群体的遗传变异水平高于LD和TP群体。同时 ,各群体中普遍存在杂合子缺失现象。太平洋牡蛎群体与其它三个褶牡蛎群体的遗传距离很小 ,甚至小于莱州和青岛的两个褶牡蛎群体间的遗传距离 0 .0 5 0 0 ,尤其是与俚岛褶牡蛎群体遗传相似度最大 ,遗传距离小于其它各群体之间的距离 ,仅为 0 .0 0 99。     

Functional efficacy analysis of Angelica gigas Nakai on chicken myoblast cells through cell‐based in vitro assay

The value‐added products in livestock industry is one of the key issues in order to maximize the revenue and to create a new business model. Numerous studies have suggested application of herbal plants as feed additives to increase health, productivity, and/or high‐quality product in livestock. In this study, the first experiment was designed to develop in vitro evaluation system by using primary chicken myoblast (pCM) cells isolated from pectoralis major of 10‐day‐old male embryos. Subsequently, to evaluate effects of Korean Danggui Angelica gigas Nakai (AGN), we optimized the concentration of AGN root extract for treatment of primary pCM cells. After the treatment of AGN root extract, we compared proliferation and differentiation capacity, and also examined the gene expression. In the second experiment, the next generation sequencing analysis was performed to compare the different patterns of the global gene expression in pCM cells treated with AGN extract. Three up‐regulated (pancreas beta cells, fatty acid metabolism and glycolysis) and one down‐regulated (adipogenesis) gene sets were characterized suggesting that the AGN extract affected the metabolic pathways for the utilization of fat and glucose in chicken muscle cells. Furthermore, we validated the expression patterns of the up‐regulated genes (GCLC, PTPN6, ISL1, SLC25A13, TGFBI, and YWHAH) in the AGN‐treated pCM cells by quantitative RT‐PCR. These results demonstrated that the treatment of AGN extract decreased proliferation and differentiation of pCM cells, and affected the metabolic pathways of glucose and fatty acids. Moreover, AGN extract derived from byproducts such as stem and leaf also showed the reduced proliferation patterns on AGN‐treated pCM cells. Taken together, pCM cell‐based in vitro assay system could be primarily and efficiently applied for evaluating the biofunctional efficacy of various feed additive candidates.     

智利外海茎柔鱼渔获率及钓捕技术的初步研究

根据2006年4-6月我国鱿钓船对东南太平洋智利外海茎柔鱼资源探捕,对捕捞产量及其钓捕技术进行了分析。探捕期间,其产量以手钓为主,约占总产量的98%。试验表明,八角型手钓钩的脱钩率为6.5%-19.5%,平均为13.2%。船体后部和前部的手钓脱钩率较高,中部较低。机钓脱钩率为20.7%-46.2%,平均为32.9%。茎柔鱼对机钓钩的颜色具有选择性,其中荧白色机钓钩的钓获率为最高,其次为绿色,橙色为最低。集鱼灯为金属卤化物灯时（2kW×180盏）,八角型手钓钩的钓捕产量比四角型手钓钩高0.5倍;凌晨02：00-03：30时采用高压钠灯时（30盏×500W）,四角型手钓钩反过来比八角型手钓钩高0.35倍。     

Pathology and mass mortality of Pacific oysters, Crassostrea gigas (Thunberg), in 2005 at the East Frisian coast, Germany

In 2005, Pacific oysters, Crassostrea gigas , were collected from May to September along the East Frisian coast and processed for histology. Because of mass mortalities in September, additional samples of moribund oysters and apparently healthy blue mussels, Mytilus edulis , were subjected to virological and ultrastructural investigation. The oysters displayed a variety of pathological conditions including viral gametocytic hypertrophy which is reported here for the first time from the German coast. Haemocyte aggregations in the digestive tract, in the intestinal mucosa and submucosa, in the mid-gut gland and in the ventricle of the heart were commonly observed at some stations. In association with mass mortalities, severe gill necrosis occurred which may have contributed to the high mortality rates. Total mortality rates of up to approximately 60% were seen. All size classes and thus age classes of oysters were affected, with highest mortality rates within the youngest age classes which had just reached sexual maturity (shell lengths <40 mm). The smallest dead oysters had shell lengths of 10 mm. The phenomenon was mainly restricted to C. gigas stocks in harbours, probably because of favourable conditions for infection, i.e. limited water exchange, less food availability, reduced oxygen content and higher pollution levels.     

Seasonal variation in the condition index of Pacific oyster postlarvae (Crassostrea gigas) in a land‐based nursery in Sonora,Mexico

This study examined the seasonal variation in the condition index (CI) of Crassostrea gigas postlarvae (<5 mm) that were cultivated at a commercial hatchery. Oysters were sampled weekly at the nursery using seawater from a lagoon for the grow‐out that precedes commercialization. Temperature, salinity, seston, chlorophyll a, oxygen and pH were recorded at each sampling and water samples were taken to identify phytoplankton groups and their abundance. High levels of primary productivity, chlorophyll a and seston were detected during summer, but the highest CI occurred in winter. During winter, elevated phytoplankton biomass was composed by diatoms and phytoflagellates, which served as the main food source and promoted weight gain in this season. Variations in salinity, oxygen and pH were not related to differences in the CI. However, it appears that the wide temperature variation affected functions, such as feeding activity, apparently enhancing ingestion during winter (mean 16.5±1.4 °C) and reducing ingestion during summer (mean 31±1.5 °C). Winter production resulted in postlarvae with a homogeneous size range and a high CI, indicating that winter is more favourable to start cultivation. The CI represents a practical means to determine the physiological state of postlarvae before transfer to cultivation sites.     

Genetic differentiation between Zhe oyster Crassostrea plicatula and pacific oyster Crassostrea gigas populations in China assessed by microsatellite analysis

ABSTRACT:   Genetic differentiation and relationships between Crassostrea plicatula and Crassostrea gigas populations from China were studied by means of the microsatellite technique. Seven loci were used to screen five populations each collected from C. plicatula and C. gigas . All loci showed high polymorphism for all populations, as observed in average number of alleles per locus (19.1–28.1), and average expected heterozygosity (0.891–0.954). Significant departures from Hardy–Weinberg equilibrium due to heterozygote deficiency were observed over most populations at each locus and were best explained by null alleles. F _ST values showed significant genetic differentiation between C. plicatula and C. gigas populations. According to the neighbor-joining tree constructed on the basis of the genetic distance ( D _A), the ten populations fell into two distinct groups ( C. plicatula and C. gigas groups), and the results of principal coordinate analysis and assignment tests also supported the neighbor-joining clustering. The outcomes presented here suggested that the microsatellite markers have great potential for differentiating C. plicatula from C. gigas populations. The information obtained in this study has important implications for the suitable management and conservation of these genetic resources in China.     

太平洋牡蛎二倍体和三倍体的生长比较

比较研究了在福建养殖的太平洋特蛎二倍体和三倍休的生长，结果表明，经１７个月养殖的太平洋牡蛎三倍体壳长、壳高、体重和软体部重量分别比二倍体增加１４．４１％、７．６６％、３５．２７％和７３．２５％。在太平洋特蛎繁殖季节５￣８月，三倍体体重和软体部重量生长明显超过二倍体．还就温带及亚热带海区养殖的太平洋牡蛎二倍体和三倍体的生长进行讨论。     

基于不同权重栖息地模型的秘鲁外海茎柔鱼渔场分析

根据2006-2014年春季(8月~10月)、夏季(11月~翌年1月)、秋季(2月~4月)、冬季(5月~7月)秘鲁外海茎柔鱼渔获数据,结合3个关键海洋环境因子海表面温度(SST)、海表面高度(SSH)和净初级生产量(NPP)的数据,利用不同权重方案的栖息地适应性指数模型来分析秘鲁外海茎柔鱼渔场分布。利用单位捕捞努力量渔获量(CPUE)与SST、SSH和NPP建立适应性指数(SI)模型,采用算术加权法建立综合适应性指数(HSI)模型,依据捕捞量和努力量的比重来比较不同权重的HSI模型,选择不同季度下的最优模型,并用2015年的数据进行验证。结果显示,茎柔鱼CPUE 和渔场纬度重心(LATG)呈现显著的年际和季节变化。不同季节茎柔鱼最优栖息地模型中的权重方案不同,其中春季最优模型权重方案为案例9,权重比例最高的环境因子是SST；夏季最优模型权重方案为案例7,SST、SSH和NPP所占的权重比例均等；秋季最优模型权重方案为案例3,权重比例最高的是SSH；冬季与春季相同。研究表明,影响秘鲁外海茎柔鱼栖息地分布的环境因子随季节具有显著差异,春冬季节最主要的环境因子是SST。此外,建立茎柔鱼的栖息地预测模型需考虑环境因子权重以区分影响差异。