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1.
Movement behaviour of large female yellow European eel (Anguilla anguilla L.) in a freshwater polder area 下载免费PDF全文
Pieterjan Verhelst Jan Reubens Ine Pauwels David Buysse Bart Aelterman Stijn Van Hoey Peter Goethals Tom Moens Johan Coeck Ans Mouton 《Ecology of Freshwater Fish》2018,27(1):471-480
Due to a recruitment decline of more than 90% in 30 years, the European eel (Anguilla anguilla L.) has been classified by IUCN as critically endangered. Although the species has been studied intensively to obtain knowledge to improve management, studies about the resident yellow stage are relatively scarce. In this study, 52 large female yellow eels were tagged with acoustic transmitters in a Belgian polder system and tracked by a network of 23 automatic listening stations. We studied both circadian and seasonal movement patterns and the effect of environmental variables on these patterns. Large female yellow eels were most active at night in late summer and early autumn. A generalised linear mixed model showed that their movement is only slightly influenced by environmental variables. Moreover, as yellow eels show high site fidelity (i.e., the majority was detected only in the habitat type of their catch‐release location), they do not encounter many human‐induced connectivity problems in polder systems, which makes these systems highly suitable as eel growth habitat. These results can contribute to an effective eel management regarding habitat protection and restoration. 相似文献
2.
本文以日本农副产品加工产品的发展历程为切入点,利用SWOT分析法对日本农副产品加工产业的优势与劣势、机遇与挑战进行了较为深入的分析,并最终根据分析结构提出了部分我国相关产业发展的启迪。 相似文献
3.
旨在研究自噬调控药物对感染日本脑炎病毒(Japanese encephalitis virus,JEV)小鼠脑部细胞凋亡的影响,本试验建立自噬调控药物处理的感染日本脑炎病毒小鼠的动物模型,其中,雷帕霉素为自噬诱导剂,渥漫青霉素及氯喹为自噬抑制剂。实验动物分成8组:DMEM对照组(Control);JEV感染组(JEV);JEV+雷帕霉素(Rapamycin)组(JEV+Rapa);JEV+渥漫青霉素(Wortmannin)组(JEV+Wort);JEV+氯喹(Chloroquine)组(JEV+CQ);雷帕霉素组(Rapa);渥漫青霉素组(Wort);氯喹组(CQ)。观察不同处理组小鼠的临床症状;透射电镜观察小鼠脑部神经元及胶质细胞的线粒体损伤程度;Tunel染色观察统计小鼠脑部凋亡细胞分布;检测小鼠脑部凋亡因子及凋亡蛋白的表达量。与JEV+Rapa及JEV组相比较,JEV+Wort及JEV+CQ组小鼠出现轻微的神经症状,脑部神经元及胶质细胞线粒体轻度损伤,脑组织较少细胞发生凋亡。不同处理组小鼠脑部凋亡因子及凋亡蛋白的表达量变化差异不显著。综上表明,自噬抑制剂渥漫青霉素和氯喹可以在一定程度上抑制感染日本脑炎病毒小鼠脑组织中细胞凋亡的发生。 相似文献
4.
[目的/意义]中之岛图书馆是日本少见的经营商店的公共图书馆,其文创产品的开发和销售是日本公共图书馆在文创产业中的缩影,它以品类丰富的文创产品,可爱精致的风格和清新时尚的推广方式而成为公共图书馆经营图书馆商店的佼佼者。其在文创上的思维和运营方式,亦有可圈可点之处。[方法/过程]本文调研了中之岛图书馆商店的商品,整理了其图书馆商店中文创产品的形式与内容,分析了其文创产品的特征,提炼了几点其在文创产品生产与销售过程中的经验。[结果/结论]中之岛图书馆商店遵循丰富、可爱、小巧、实用的产品设计原则,其利用图书馆商品进行图书馆形象宣传、结合当地文化设计产品的理念、利用商品与公众建立良好的互动关系、挖掘商品的教育功能、时尚的推广方式等经验,可为同行进入文创领域提供一定的启发和借鉴。 相似文献
5.
First identification and characterization of Tenacibaculum dicentrarchi isolated from Chilean red conger eel (Genypterus chilensis,Guichenot 1848) 下载免费PDF全文
6.
Anthropogenic spreading of anguillid herpesvirus 1 by stocking of infected farmed European eels,Anguilla anguilla (L.), in the Schlei fjord in northern Germany 下载免费PDF全文
The Schlei fjord in northern Germany is the recipient water of a comprehensive eel, Anguilla anguilla (L.), stocking programme. Since 2015, stocked eels become alizarin red S marked, but to date no control mechanism is implemented in this stock enhancement measure to prevent anthropogenic spreading of diseases. Consequentially, it was possible that farmed stocking cohorts of 2015 and 2016 (in total ca. 1040 kg) were subsequently tested positive for anguillid herpesvirus 1 (AngHV 1). For this study, 100 eels [total length (TL) 24.3–72.9 cm, age ca. 1–6 years] were caught in 2016 and investigated with regard to AngHV 1 infection, parasite load (Anguillicoloides crassus) and body conditions. 68% of the eels were found to be virus positive while larger specimens were more often infected. In addition, a fitted generalized linear model (area under the curve = 0.741) demonstrated that an increase in individual TL is accompanied with an increased risk of clinically relevant virus loads. Anguillicoloides crassus turned out to be an important stressor for eels, because parasite and virus load revealed a significant positive correlation. The results of this study evidently show the urgent need of a disease containment strategy for eel stocking programmes. 相似文献
7.
Teruo Nakayama Keiko Hatae Midori Kasai Atsushi Ooi 《Journal Of Aquatic Food Product Technology》2017,26(5):578-592
The season for finding the firmest sashimi made from wild Japanese sea bass was investigated. Flesh rigor tension and contraction were measured by a “new” device with isometric (muscle length kept constant) and isotonic (balance beam moves freely) transducers. Both flesh rigor tension and contraction peaks appeared at the same postmortem times, with attainment of ultimate pH and adenosine triphosphate/inosine monophosphate ratio in four seasons. Seasonal seawater temperature correlated negatively to seasonal maximum rigor contraction and positively to seasonal flesh breaking strength at 72 h postmortem. After rigor peak tension attainment, the tension relaxation was much lower than that of other wild fish species, especially in summer. The sea bass muscle resisted structure disruption in rigor isometric tension generation. Wild sea bass sashimi was firmest in breaking strength in summer. 相似文献
8.
Geosmin depuration from European eel (Anguilla anguilla) is not affected by the water renewal rate of depuration tanks 下载免费PDF全文
Edward Schram Tobias van Kooten Jan W van de Heul Johan W Schrama Johan A J Verreth Albertinka J Murk 《Aquaculture Research》2017,48(9):4646-4655
This study established that geosmin depuration from European eel is not affected by the water renewal rate of depuration tanks. A general fish bioaccumulation model extended with terms that account for effects of tank water renewal rate and system losses of chemicals, predicted strong effects of the water renewal rate of depuration tanks on geosmin depuration from European eel. Model predictions were validated in a depuration experiment with geosmin‐loaded European eel (n = 95) with a mean (SD) individual weight of 134.4 (5.0) g and a mean (SD) lipid content of 33.7 (2.8) % (w/w). Fish were depurated for 24, 48 or 72 h at three different tank water renewal rates (0.3, 3.3 and 33 day?1). Treatments were installed by three different mean (SD) water flow rates (13.8 (1.3), 143.5 (9.2) and 1511 (80) L kg fish?1 day?1) over 30‐L tanks. Eels eliminated geosmin from their bodies, but unlike the model predicted, this was independent of the water renewal rate of the depuration tanks. Although being eliminated from the fish, geosmin hardly appeared and certainly did not accumulate in the water of the depuration tanks as the model predicted. This observation may be explained by geosmin being eliminated from eel as metabolite rather than the parent compound. Geosmin elimination from eel seems not to occur according to the generally accepted passive diffusion mechanism for excretion of lipophilic chemicals, and geosmin biotransformation by the eel seems indicated. Clearly geosmin depuration from European eel cannot be enhanced by increasing water renewal rates of depuration tanks. 相似文献
9.
Monitoring of acute phase proteins such as serum amyloid A at gene expression level may provide quick information about immune status of the host and its susceptibility towards common infections. Present study was carried out to evaluate and compare the mRNA expression of SAA gene in Rhode Island Red chicken (RIR) and Japanese quails using real time PCR analysis in response to inactivated Salmonella gallinarum culture. The results showed that expression of SAA gene was approximately 17–33 folds higher in case of birds administered with bacterial culture when compared to un-inoculated controls and expression was higher and quicker in case of quails than RIR chicken. The SAA genes from chicken and quail were cloned and upon sequence analysis it was observed that deduced amino acid sequence of SAA from chicken and quails were having approximately seven percent variation which might have significance in function of this protein in these species. 相似文献
10.
Population pharmacokinetics of methadone hydrochloride after a single intramuscular administration in adult Japanese sika deer (Cervus nippon nippon) 下载免费PDF全文
Christopher Scala Amélie Marsot Marie‐Josée Limoges Yann Locatelli Nicolas Simon Jean‐Claude Alvarez 《Veterinary anaesthesia and analgesia》2015,42(2):165-172
ObjectiveTo assess the population pharmacokinetics of methadone in deer.Study designProspective non-randomized experimental trial.AnimalsTwelve healthy adult sika deer (nine males and three females).MethodsDeer received intramuscular administration of racemic methadone hydrochloride at 0.5 mg kg−1 or 1 mg kg−1. Plasma methadone and its metabolite 2-Ethylidene-1,5-Dimethyl-3,3-Diphenyl-Pyrolidine (EDDP) concentrations were determined by validated liquid chromatography coupled to tandem mass spectrometry methods, at times 0, 30 minutes, 1, 2, 3, 4, 5, 6, 8, 12 and 24 hours. Population pharmacokinetics analysis was undertaken using a non-linear mixed effects modelling (NONMEM).ResultsA two-compartment linear disposition model best described observed time-concentration profiles of methadone and EDDP. Population parameter estimates of methadone were elimination clearance (17.3 L hour−1), metabolic clearance (34.6 L hour−1), volume of distribution of compartment 1 (216.0 L) and volume of distribution of compartment 2 (384.0 L). Population parameter estimates of EDDP were elimination clearance (121.0 L hour−1), volume of distribution of compartment 3 (1.08 L) and volume of distribution of compartment 4 (499.5 L). The total clearance and total volume of distribution of methadone and EDDP were 51.9 L hour−1, 121.0 L hour −1, 600.0 L and 500.6 L, respectively. The methadone terminal elimination half-life was 8.19 hours. No adverse effects were observed after methadone administration.Conclusions and Clinical relevanceFollowing intramuscular injection, methadone was characterized by a large total volume of distribution, high systemic clearance and intermediate terminal half-life in sika deer. 相似文献