乙酰甲喹在美洲鳗鲡体内的药物代谢动力学及残留研究

在水温(25±1)℃条件下,分别采用口灌和浸浴的给药方式,以120mg·kg~(-1)的单剂量混饲口灌及5mg·L~(-1)浸浴18h给予乙酰甲喹后,用高效液相色谱法测定血浆、肌肉、肝脏及肾脏中的药物浓度,研究不同给药方式下乙酰甲喹在美洲鳗鲡体内的药代动力学特征及残留情况。结果表明:乙酰甲喹原药在美洲鳗鲡体内吸收良好、代谢快、体内残留少。口灌给药后,血浆中药物浓度达峰时间T_(max)为0.75h,达峰质量浓度C_(max)为4 115μg·L~(-1),消除相半衰期T_(1/2)为7.40h,总体消除率CL/F为41.89L·kg~(-1)·h~(-1),72h后血浆、肌肉、肝脏及肾脏中几乎检测不到原药;浸浴给药血浆中药物浓度于0.25h达峰,达峰质量浓度C_(max)为435.6μg·L~(-1),消除相半衰期T_(1/2)为0.26h,总体消除率CL/F为1.241L·kg~(-1)·h~(-1),2.5h后各组织中几乎检测不到原药。2种方式给药乙酰甲喹在美洲鳗鲡血浆中分布均符合药动学一室开放模型。     

磷—32玻璃微球肝动脉注射对猪肝脏毒性反应的电镜观察

为观察猪肝动脉注射磷-32 玻璃微球(32P-GMS)对肝脏急性、亚急性反应的超微结构损伤及修复过程。用7 只健康猪经切皮肝动脉内接受由选择性导管注射直径为46～76μm 的玻璃微球。其中4 只猪注射放疗性32P-GMS;3 只猪注射31P-GMS(对照)。术后2、4、8 或16 周分批取不同部位的肝组织进行电镜常规制样及电镜观察。结果选择性导管注射32P-GMS,内放射急性期(2 周时)肝细胞均出现明显的异常和严重损伤;亚急性期(4 周时)大部分肝细胞核基本正常,胞浆细胞器仍有变化;恢复期(8 周时)大部分肝细胞已修复,肝细胞基本正常,但胶原和贮脂细胞增多。内放射16 周时,肝细胞全部修复正常。观察结果表明,当吸收剂量每次不超过200Gy 的32P-GMS经肝动脉给药时,肝细胞的损伤是短期而可逆性的。     

鳗鲡养殖循环水处理系统细菌的组成及其数量

为研究鳗鲡养殖循环水处理系统中细菌的组成与数量,从循环水处理系统中的养殖池、沉淀池、生物膜池、滤池和紫外消毒池采集水样,并从生物膜池和滤池中采集附着生物样品,分别用平板菌落计数法和16S rRNA基因克隆文库分析法进行细菌计数和附着样品的细菌组成分析.结果表明：1）养殖水经过各处理环节后,水体中细菌数量逐渐减少,如由养殖池中的2.98×106CFU/L降低至牡蛎壳填料滤池中的9.30×105CFU/L,再经过紫外消毒池后,水体中细菌数量又减少了96%,再降低至3.53×104CFU/L.2）生物膜池的尼龙丝挂网载体和滤池中牡蛎壳填料上附着细菌数量较多,其数量分别高达1.39×108CFU/g和1.52×108CFU/g.牡蛎壳上的附着细菌主要分为3大类：分别属于变形菌门（包括α-、β-和γ-变形菌纲）、拟杆菌门和异常球菌-栖热菌门,其中以β-变形菌纲细菌为优势类群,大部分细菌对环境有机物具有良好的分解作用.     

不同温度下氟苯尼考在鳗鲡体内药代动力学的比较

采用对个体连续采血的方法,研究了不同水温条件下氟苯尼考以30 mg/kg的单剂量混饲口灌给药后在日本鳗鲡（Anguilla japonica）体内的药代动力学特征。利用DAS软件的统计矩原理计算每个个体的药时曲线关系,获得药动学参数,单因素方差分析结果表明,不同温度实验组间多个药动学参数存在显著性差异（P<0.05）。20 ℃、24 ℃和28 ℃实验组药物峰浓度（Cmax）分别为（7.839±1.125）、（13.010±2.334）和（18.267±3.717） μg/mL,达峰时间（Tmax）分别为（6.500±2.070）、（4.500±1.414）和（3.429±0.926） h,这表明温度越高吸收越多越快。表观分布容积（Vz/F）分别为（3.964±0.594）、（2.466±0.672）和（1.841±0.485） L/kg,表明温度较高时氟苯尼考与血浆蛋白的结合更多。平均滞留时间（MRT0-∞）分别为（31.503±7.117）、（22.881±4.940）和（22.134±6.204） h,消除半衰期（t1/2z）分别为（21.243±5.166）、（14.994±4.293）和（14.656±5.061） h,24 ℃和28 ℃水温下的消除速率显著快于20 ℃实验〖JP〗组。药时曲线下面积（AUC0-∞）分别为（235.580±62.013）、（271.983±75.023）和（353.192±92.491）μg·h/mL,表明水温对相对生物利用度有显著影响。     

循环水养殖模式下光照强度和光周期对日本鳗鲡生长及动物福利的影响

以人工捕捞的野生日本鳗鲡(Anguilla japonica)玻璃鳗苗为对象,通过控制不同的光照强度和光周期,研究在可调控的循环水系统中,光照强度和光周期对日本鳗鲡生长的影响。实验采用双因素交叉分组无重复的试验设计,即将光照强度A(10 lx、100 lx、300 lx)和光照周期B(12L∶12D、18L∶6D、24L∶0D)按照A1B1,A1B2,A1B3,A2B1,A2B2,A2B3,A3B1,A3B2,A3B3进行分组,两两相互对照,比较其生长性能和动物福利指标的变化。结果表明,不同光照强度条件下:10 lx条件下日本鳗鲡的终重(36. 43±5. 19) g、日增重(0. 27±0. 4) g和特定生长率显著低于100 lx(44. 58±6. 50、0. 34±0. 06)和300 lx(46. 13±8. 20、0. 35±0. 07)(P 0. 05),而300 lx条件下日本鳗鲡的饲料转化效率、饲料系数显著优于10 lx、100 lx(P 0. 05); 10 lx条件下谷丙转氨酶活性显著高于100 lx(P 0. 05);皮质醇在12L∶12D、24L∶0D光周期下10 lx显著低于100 lx(P 0. 05),18L∶6D条件下相反;不同光周期下:24L∶0D终重(49. 62±6. 40)、日增重(0. 35±0. 07)和特定生长率(1. 81±0. 12)显著优于18L∶6D、12L∶12D(P 0. 05),24L∶0D、12L∶12D条件下谷草转氨酶活性显著低于18L∶6D(P 0. 05),24L∶0D条件下血清甘油三酯显著高于12L∶12D(P 0. 05)。10 lx和300 lx时12L∶12D组SOD活性显著低于18L∶6D(P 0. 05),而100 lx下相反,12L∶12D皮质醇活性显著低于24L∶0D(P 0. 05),且有极显著差异(P 0. 01)。实验结果显示,不同光照强度下,300 lx时日本鳗鲡生长指标达到最佳,各项生理指标处于正常状态,同时在光周期24L∶0D时,日本鳗鲡的生长指标达到最佳,但福利条件并不是最优状态。综合生长和动物福利,12L∶12D是日本鳗最佳光周期。即循环水养殖模式下日本鳗鲡生长的最佳光照强度和福利条件为300lx、12L∶12D。研究结果为促进鳗鲡产业的发展提供了参考依据。     

Development of embryos in Mastacembelus mastacembelus (Bank & Solender, 1794) (Mesopotamian spiny eel) (Mastacembelidae)

In this study, the embryonic development of the eggs in the Mastacembelus mastacembelus (Bank & Solender, 1794) was examined. At the same time, possibilities of artificial breeding through artificial insemination were investigated. Artificial insemination was achieved by mixing the eggs of the mature female and sperm of the mature male samples caught with gill nets (22 × 22) in Ataturk Dam Lake in Turkey. To this end, first in a Petri dish (100 × 20), the testes were cut into small pieces with a lancet and the mixture of sperm–testes‐tissue was obtained. The fertilization rate of the eggs was found to be 80%. The diameter of the eggs ranged from 2.015to 1.147 mm. The perivitelline space formed 0.5 h after insemination. The first cleavage occurred at the animal pool 4 h after insemination. The oil droplets had fused to a single droplet 19 h after insemination. The blastoderm became an embryonic shield 30 h after insemination. The blastoderm covered almost half the egg 40 h after insemination and embryonic body was formed. The blastoderm covered almost the whole egg 50 h after insemination. Some somites were discernible 59 h after insemination. The embryonic body reached two‐third of the circumference of the egg 70 h after insemination. The tail bud began to separate from the yolk 77 h after insemination. A newly hatched larva was observed at 85 h after insemination.     

Water‐soluble protein level in fishmeal affects extrusion behaviour,phase transitions and physical quality of feed

The aim of this research was to investigate the effect of water‐soluble protein (WSP) as a plasticizer in the fish feed extrusion process and the impact on physical pellet quality. A three‐factor central composite design was used to study the influence of the variables WSP in the feed mix, and steam and water addition in the extruder. Regression models with r² in the range of 0.862–0.976 (P < 0.001) were established for specific mechanical energy (SME), pellet hardness, cutting strength, sectional expansion index, length, bulk density, oil adsorption capacity and extrudate flow‐starting temperature (T_f). Addition of WSP had a positive effect on SME and improved the physical pellet quality, while moisture had the opposite effect. Expansion parameters showed a complex relationship and were influenced by all the studied process variables. Increase in WSP and moisture content had a comparable effect on T_f reduction. This opens up the possibility to obtain a satisfactory ‘cook’ at reduced moisture level with a potential for significant reduction of the energy consumption during drying of the extrudate. Overall conclusion from the experiment is that WSP can be used as a processing aid for the fish feed industry, serving multiple purposes as nutrient, plasticizer and binder in extruded fish feed.     

Fyke-netting and coarse fisheries in lowland Britain: practical advice for fishery owners and managers

Abstract  The by-catches of fish, mammals and birds from a fyke-net survey of eel, Anguilla angilla (L.), stocks (total effort 1593 end days) at 45 sites in rivers and lakes in the Thames catchment and tidal river were examined. Sizes and compositions of by-catches varied between sites, yielding a total of 21 fish species representative of the types of water body sampled. The largest catches were of shoaling juvenile perch (especially in lakes). Small roach, perch and ruffe were also fairly frequent in running waters (especially the tidal and non-tidal Thames). Carp, tench and pike were less frequently caught (mainly in still waters and upper tributaries). Juvenile flounders and smelt were fairly common in the tidal Thames. Salmonids were rarely caught and fish mortalities overall were very low. Few mammals, wildfowl or crustaceans were trapped, but it is important that nets are set below water level to avoid trapping birds swimming on the surface, and the use of otter guards is recommended. Fouling of fishing tackle was rare. Recommendations are made for practical steps that can be taken to minimize undesirable impacts of commercial fyke-netting, whilst realizing the potential financial and management benefits. The cost-effective uses of fyke-nets for sampling and culling fish for management purposes are discussed.     

结晶紫在鳗鲡组织中的代谢和消除规律研究

在水温18—21℃，结晶紫浓度为0．1mg／L的条件下，对鳗鲡进行24h药浴后，采用高效液相色谱-串联质谱仪，对鳗鲡肌肉组织中的结晶紫和隐色结晶紫含量进行连续56d的监测。结果表明：鳗鲡肌肉组织中结晶紫的最高浓度出现在给药后12h；在整个监测过程中，肌肉组织中结晶紫的含量都较低（0～3．91μg／kg）；药浴336h后，结晶紫未检出。结晶紫在鳗鲡组织中代谢为隐色结晶紫的速度很快，药浴后3h即可测得隐色结晶紫，且含量明显高于结晶紫。隐色结晶紫的最高含量出现在药浴后的72h。在监测的第56天，隐色结晶紫的含量仍达19．5μg／kg。可见，隐色结晶紫在鳗鲡肌肉组织中的消除过程长，是鳗鲡机体肌肉组织中药物存在的主要方式。     

养鳗池塘生态系统中矿物元素及其影响因素

对比分析了6口处于不同养殖阶段的日本鳗鲡(Anguill japonica)池塘水体、水源、底泥及饲料中的矿物元素,探讨了池塘生态系统中矿物元素的主要影响因素和生产管理对策,结果表明:1)养鳗池塘水体矿物元素与所处养殖阶段投入饲料的品种相关,底泥中矿物元素部分在养殖过程中积累而来;2)主成分分析结果表明钙、镁、铝元素是...