7种常用渔药对海水闭合循环系统生物滤器硝化作用的影响

在海水闭合循环系统中加入常用剂量的呋喃唑酮 (C8H7N3 O5)、甲苯咪唑 (C16H13 N3 O3 )、土霉素 (C2 2 H2 4N2 O5.2H2 O)、氯霉素 (C11H12 O5N2 Cl2 )、CuSO4 FeSO4合剂、强氯精 (C3 Cl3 N3 O3 ,有效氯 6 2 .5 % )、甲醛 (CH2 O)等 7种常用渔药 ,确定系统把 10mg/L总氨氮 (NH4 N)硝化至较低水平 (CNH4 N<0 .0 5mg/L ,CNO2 N<0 .0 1mg/L)所需的时间及氧化过程中各主要水质指标的变化 ,并以此作为判断生物滤器的硝化能力是否受到影响的依据。结果表明 ,分别加入甲苯咪唑至 1、2、3mg/L(全水体质量浓度 ,其他同此 )、CuSO4 FeSO4合剂 (0 .5 0 .2 )mg/L、土霉素 1mg/L、氯霉素 1、2、3mg/L均对生物滤器硝化作用无明显影响 ;土霉素 2、3mg/L、强氯精 1mg/L或甲醛 10、2 0、30、4 0mg/L影响生物滤器对亚硝酸氮的氧化 ;分别以呋喃唑酮 1、2、3mg/L、重复添加氯霉素至 3mg/L、重复或直接添加强氯精至 2mg/L都影响氨氮、亚硝酸氮的氧化     

罗非鱼、南美白对虾体内药残状况研究

以广东省养殖罗非鱼及南美白对虾为实验对象,就其体内土霉素等多种渔药残留及分布状况进行研究, 比较不同规格罗非鱼及南美白对虾体内渔药残留差异,分析渔药在罗非鱼及南美白对虾不同部位的残留状况。结果表明在罗非鱼体内已烯雌酚、呋喃唑酮、氯霉素3种渔药未见检出,南美白对虾体内已烯雌酚、呋喃唑酮、氯霉素、(口恶)喹酸和喹乙醇5种渔药均未见检出,而土霉素等常规用药在罗非鱼和南美白对虾体内均有不同程度的检出。渔药残留量因其规格大小及部位而异,趋势为大规格样品渔药残留量相对较高,在罗非鱼及南美白对虾体内的增长情况与其体重具有负相关性;罗非鱼内脏渔药残留量明显高于肌肉组织,虾头为虾渔药残留的主要场所。     

The pharmacokinetics of common chemotherapeutic drugs used in veterinary medicine

The present paper summarizes the pharmacokinetics of chemotherapeutic agents commonly used in controlling bacterial disease in animals. Data on absorption, distribution and excretion of chemotherapeutic agents are given in form of tables. It is explained that pharmacokinetic parameters of antimicrobial chemotherapy among others are influenced by the drug's pharmaceutical formulation, its route of administration, its biotransformation and also by the age of the patients. There are given hints for handling the drug in order to achieve optimal effects.     

Different combinations of protein ingredients in carp diets for reducing phosphorus loading

ABSTRACT: This study was conducted to gather data on the reduction of environmental phosphorus (P) loading through the formulation of carp diets with different combinations of protein ingredients. Five experimental diets were formulated by substituting fishmeal (FM; 10–20%) with alternative protein sources such as meat meal (MM; 5–15%), blood meal (BM; 5–7%), and defatted soybean meal (dSBM; 6–10%). The control diet used was a commercial carp diet selected based on earlier experiments. Each diet was fed to duplicate groups of juvenile carp three times a day, until satiation for 12 weeks. Feed performance was proportional to the increase in dietary FM levels. Phosphorus absorption ranged between 41.6% and 52.0% among the experimental groups and was 42.6% for the control group, but there were no marked differences in nitrogen (N) absorption rates. Phosphorus retention ranged from 31.4% to 35.7% for the test diets, whereas N retention increased proportionally with dietary FM levels and ranged from 34.7% to 41.7%. The P and N retention values of the control diet were 27.6% and 41.2%, respectively. The total P loading (T-P) increased at the higher FM levels (9.1–10.7 kg/t production), whereas lower FM levels produced higher total N loading (T-N, 34.6–43.1 kg/t production), the figures for the control being 13.9 T-P kg/t production and 35.6 T-N kg/t production. These results indicate that the reduction of FM levels to 10–20% by replacing it with MM, BM, and dSBM in carp diets was effective in reducing the loading of P and N.     

Current practices in the chemotherapeutic control of sea lice infestations in aquaculture: a review

Abstract. This review surveys the available literature on the efficacy and ecotoxicology of chemotherapeutic agents for the control of sea lice (Copepoda: Caligidae) infestations in marine aquaculture. To date, treatment for the disease has relied almost exclusively on the use of the organophosphorus pesticides, trichlorfon and dichlorvos. While use of dichlorvos and trichlorfon appears to have little, if any, environmental impact, protracted use in some areas has led to reduced efficacy. Compounds proposed for sea lice control currently under field evaluation include azamethiphos (organophosphate), ivermectin (avermectin), pyrethrum (pyrethrin) and hydrogen peroxide. Although all of these compounds are effi cacious, at present published information on marine environmental toxicology is scarce and is limited to in vitro toxicity testing. Other compounds that have been considered for sea lice control include formalin, malathion (organophosphate), carbaryl (carbamate), diflubenzuron (insect growth regulator) and natural remedies (i.e. onions and garlic). In general, formaldehyde (aldehyde), malathion and natural compounds show either poor efficacy or unsuitable therapeutic margins. Although carbaryl and diflubenzuron are both efficacious and exhibit suitable therapeutic margins, available data suggests that the compounds, due to undesirable environmental toxicological characteristics, would be unsuitable for sea lice control.     

Effects of formalin chemotherapeutic treatments on biofilter efficiency in a marine recirculating fish farming system

Formalin (a 33–38% aqueous formaldehyde solution) is currently used for bath treatments to control ectoparasitic infections of fish. Its effects on nitrification were evaluated in a semi-closed pilot scale saltwater recirculating turbot culture system. Tested treatments included 1 h static exposure to 20, 30, 40, 50, 60, 70, 90 mg l⁻¹ formaldehyde without flushing, and long-term (i.e., 2, 4 and 6 h) exposures with constant 60 mg l⁻¹ formaldehyde in a recirculating system. Formaldehyde has no apparent effect on the ammonia oxidative bacterial community. However, a significant effect on nitrite oxidation was observed in 1 h static exposures of concentrations higher than 40 mg l⁻¹, and in recirculating system exposures of 60 mg l⁻¹ formaldehyde for more than 4 h. Repeated treatments may be hazardous for nitrifying bacteria, which could induce an increase in nitrite concentration. Nitrite concentrations should be monitored when treatments are repeated or when they last a long time in recirculating aquaculture systems.     

微生态制剂在水产养殖中的应用

微生态制剂(Microbial ecological agent)又名微生态调节剂、益生菌、活菌制剂等。是根据微生态学原理从天然环境中筛选出来的微生物菌体，经培养、分离、纯化、繁殖后制成的含有大量有益菌的活菌制剂。其作用主要是维持并调节系统的微生态平衡、提高养殖动物的免疫力和抗“应激”能力、抑制病原微生物、降     

大菱鲆不同进口群体杂交后代的早期生长差异

2003-2005年间,分5批收集不同批次进口的大菱鲆群体,从各群体中挑选性腺发育良好的个体,利用人工授精技术,通过不平衡巢式交配设计,构建了5种杂交组合,测试其杂交子一代生长性能,为培育优良的大菱鲆养殖新品种提供基础资料.5个杂交组合共生产31个家系,在初孵仔鱼第25天和第80天,从每个家系随机取样50尾,测定其体长、体重等性状值,计算各杂交组合和家系25～80 d的绝对增重率,通过方差分析、聚类分析比较各组合、家系间的生长性能的差异,并对不同家系25 d和80 d的体长体重相关性进行了分析.结果表明:杂交组合25 d、80 d体重性状间存在较大变异,80 d体重LSD多重比较显示丹麦与法国进口群体的杂交组合(D×F)子一代生长优于其它杂交组合.系统聚类分析表明,丹麦×智利(D×C)组合与丹麦×法国(D×F)组合生长性能较为接近聚为一类,丹麦×西班牙(D×S)组合、丹麦×英国(D×E)组合和英国×西班牙(E×S)3个组合聚为一类,且前者的生长速度高于后者.家系间生长性能聚类分析表明,生长速度最快的家系分布在不同的杂交组合,80 d体重的组合内家系间方差分析也表明组合内家系间存在较大变异.组合间和家系间生长分析发现大部分组合和家系在25 d和80 d的体长、体重性状值排序上不一致.家系相关分析表明,25 d体长、体重与80 d体长、体重间相关系数(0.132、0.096)和决定系数(0.017、0.009)均较小,25 d体长体重对80 d体长体重的影响甚微.     

不同饵料及其组合对黑鲍幼鲍生长及存活的影响

试验研究人工配合饲料、细基江蓠繁枝变种(Gracilaria tenuistipitata)(下称江蓠)、江蓠 裂片石莼(Ulva faxciata)、江蓠 肠浒苔(Enteromorpha intesinalis)、江蓠 裂片石莼 肠浒苔共5种饵料搭配方式对黑鲍幼鲍生长和存活的影响。试验进行35d,结果表明:(1)不同试验组之间的幼鲍的存活没有显著影响(P>0.05)。(2)不同试验处理对幼鲍的生长有显著影响(P<0.05)。江蓠 浒苔组、人工配合饲料组的黑鲍的特定生长率都显著大于其它饵料组(P<0.05);饲喂混合海藻的黑鲍的特定生长率显著大于单一海藻组(P<0.05)。壳长增长率、湿重增重率和干重增重率亦呈相似趋势。(3)幼鲍对不同饵料组合的转化效率存在显著差异(P<0.05)。试验结果表明,在水温较高时用江蓠、石莼和浒苔组成的混合饵料代替人工配合饲料饲养幼鲍,同样可以达到高的生长率。     

不同生物饵料组合对脊尾白虾幼体变态发育的影响

本研究以脊尾白虾(Exopalaemon carinicauda)幼体为研究对象,研究了牟氏角毛藻(Chaeroeeros moelleri)、褶皱臂尾轮虫(Brachionus plicatilis)和卤虫(Artemia salina)无节幼体搭配投喂对脊尾白虾幼体的存活率(SR)、变态发育和消化酶的影响。结果显示,单一卤虫组的幼体变态发育速度最快,14 d内全部变态为仔虾,其他3组则需要15 d;单一卤虫组、牟氏角毛藻+卤虫组和轮虫+卤虫组的幼体变态为仔虾时的SR分别为84.33%、84.67%和83.00%,各组间差异不显著(P>0.05);投喂牟氏角毛藻+轮虫+卤虫混合饵料组的幼体在Z5~P阶段大量死亡,变态为仔虾时的SR为35.67%。单一卤虫组投喂的脊尾白虾幼体的胃蛋白酶(1.94 U/mg prot)、脂肪酶(2.35 U/mg prot)和α-淀粉酶(0.13 U/mg prot)活力在4个组中最高,牟氏角毛藻+轮虫+卤虫组的胃蛋白酶(0.08 U/mg prot)、脂肪酶(0.91 U/mg prot)和α-淀粉酶(0.08 U/mg prot)活力在4个组中最低;牟氏角毛藻+卤虫组和轮虫+卤虫组的α-淀粉酶活力均为0.12 U/mg prot,而轮虫+卤虫组幼体的脂肪酶(1.78 U/mg prot)和胃蛋白酶(0.39 U/mg prot)比牟氏角毛藻+卤虫组分别高0.35和0.04 U/mg prot。研究表明,在脊尾白虾育苗过程中,投喂卤虫无节幼体(3~5 ind./mL),能提高幼体SR和加快变态发育速度,同时,在养殖过程中加入一定的牟氏角毛藻可减缓养殖水体恶化的速度。     

Effect of fish species combinations on water chemistry and plankton composition in earthen fish ponds

Fish-environment relationships in ponds with several different combinations of fish species are analysed. The study was carried out in 18 earthen fish ponds in a farm at Lohamei HaGetaot, Israel, during the 1986 fish culture season. Water was analysed for temperature, dissolved oxygen, pH, ammonium, nitrite, nitrate, and phyto- and zooplankton. Factor analysis was applied to the physico-chemical and plankton datasets to identify respectively the main ecological processes and species groups in the ponds. The general linear model was applied to analyse the effect of fish species combination and month on the ecological and plankton factors identified. The main source of water quality variability was accounted for by three factors: pond loading (CHF1), oxygenation of the water (CHF2), and pH effect on the second step of nitrification (CHF3). The main source of variability in the plankton composition was due to presence or absence of a blue-green algal bloom (PLF1). Another four plankton factors were identified. Each factor was differently affected by the fish species combination in the pond and the month. The complex nets of interactions between common carp, tilapia and mullet, and how these fish in different cominations affect pond water quality and food webs are discussed.     

Preliminary investigations into the suitability of a new chemotherapeutic,furanace, for the treatment of infectious prawn diseases

Furanace appears to be of excellent potential for the chemotherapeutic control of most potential and possible prawn diseases. It shows antimicrobial activity over a wide range of bacterial and fungal pathogens of fish and crustacea. It is non-toxic at treatment levels to macrobrachium rosenbergii, the prawns rapidly absorb the drug, tissues achieve effective drug levels, and the compound is rapidly excreted after treatment.     

Toxicity of four commonly used chemotherapeutic compounds to fry of the African catfish, Clarias gariepinus (Burchell)

Acute toxicity tests were carried out for four compounds commonly used against various fish pathogens to determine their 24-h LC₅₀ values to fry of the African catfish, Clarias gariepinus (Burchell). Compounds tested and their calculated 24-h LC₅₀ values (mg l^?1) were as follows: praziquantel (13.4); malachite green oxalate (0.14); acriflavin neutral (10.0); and mebendazole (315). The results show that dosage levels of malachite green oxalate, praziquantel and acriflavin neutral recommended in the literature for the control of most fish ectoparasitoses caused substantial mortalities and cannot be applied to Clarias gariepinus fry.     

Culture-based fisheries in small reservoirs in northern Vietnam: effect of stocking density and species combinations

This study was conducted in 20 reservoirs, ranging in size from 4 to 30 ha, in the mountainous, northern region of Vietnam, in ThaiNguyen and YenBai provinces, over two growth cycles in 2002/03 and 2003/04. The reservoirs are leased by farmers for fishery activities from the provincial administration, and the trials were managed by the lessee farmers. Three species combinations in ratios (by fingerling weight) of grass carp: silver carp: bighead carp: common carp: mrigal 1:2:1:1:3 (A), 1:3:1:1:2 (B) and 1:2:1:1:2 (C) were used as seed stock. The overall mean yield of stocked fish in 2002/03 and 2003/04 growth cycles in reservoirs in ThaiNguyen and YenBai provinces was 165 (±21) and 190 (39), and 287 (±22) and 325 (±24) kg ha^?1 respectively. The yield in reservoirs in both provinces, in both growth cycles and irrespective of the species combinations, increased in relation to stocking density. In reservoirs in ThaiNguyen Province, the species combination B gave the lowest yield (both growth cycles and overall), and differed significantly (P<0.05) from combinations A and C. The stocking efficiency (ratio of the yield of stocked fish in kg ha^?1 to the weight of the stocked fish in kg ha^?1) in reservoirs in ThaiNguyen Province ranged from 2.9 to 5.1 over the two growth cycles and that in YenBai from 2.8 to 3.9. There was no discernible trend between growth cycles and/or between species combinations. The major cost incurred was for fingerling procurement. In all instances, a net profit was accrued. The mean (±standard error (SE)) net profit ha^?1 (in 10³VN dong; approximately 15 500 VND=1 US$) was 885 (±270) and 864 (±214), and 1322 (±176) and 1600 (±150) for the growth cycles 2002/03 and 2003/04 for reservoirs in ThaiNguyen and YenBai provinces respectively. Between the two growth cycles, the net profit increased in eight and three reservoirs from YenBai and ThaiNguyen, respectively, the maximum increase being recorded in Khuan Gio (165%) and Dong Man (39%) reservoirs.     

不同施肥组合对盐碱地凡纳滨对虾池塘中浮游生物的影响

本实验在山东省东营市黄河口毛蟹繁育中心的养殖池塘的12个陆基围隔(5.5m×5.5m)中进行.在N施加量相等、N/P质量比为10∶1的情况下,实验共设4个处理,分别为全部施加无机肥(NN)、1/3有机肥和2/3无机肥(NO)、2/3有机肥和1/3无机肥(ON)以及全部施加有机肥(OO).凡纳滨对虾(Penaeus vannamei)的放养密度均为33ind/m2.实验结果表明,全部施加无机肥的水体中浮游植物生物量显著高于其他组合,其浮游动物生物量高峰维持时间最短;2/3有机肥与1/3无机肥混施的水体中浮游植物生物量最稳定,而且浮游动物高峰维持时间最长,与其他组合相比能显著提高对虾的净产量;全部施加有机肥的水体中浮游植物多样性指数显著高于其他组合.     

Growth performance,feed utilization and body composition of Dentex dentex fed on different macronutrient combinations

Determining an adequate macronutrient balance is essential to guarantee the production success. As protein is the limiting component for fish food, the utilization of lipids or carbohydrates as partial substitutes of this nutrient is a challenge to improve its use. In order to get an approximation of the maximum levels of utilization for carbohydrates and/or lipids and determine the most adequate macronutrient to partly replace protein as the main energy source of diets for dentex (91.7 ± 1.4 g mean weight), four experimental diets with different protein:lipid:carbohydrate percentages (43/16/28, 43/24/4, 38/19/28 and 38/24/13) were tested for 13 weeks. The results indicated the possibility of using 38% of dietary protein without affecting growth performance, under the experimental conditions. There were no differences among the four diets either in most of the nutritive utilization indicators or in the body composition and haematological parameters. The influence of dietary composition was only observed in the feed intake, being higher with more dietary carbohydrates, and the hepatosomatic index and protein efficiency ratio, showing more elevated values in diets with a higher lipid level. The dentex capacity of using both carbohydrates and lipids efficiently to obtain the necessary energy for its correct growth, as well as to compensate the energetic ‘vacuum’ caused by the dietary protein reduction, under the assayed conditions, was confirmed.     

水产养殖中的无公害水质调节剂

近年来，随着养殖密度的不断加大，造成疾病的并发、混合感染，加大了用于疾病防治的药物投入，使管理成本上升，形成恶性循环。另外，大量药物的使用，往往没有考虑生态环境的影响，破坏水环境的自然平衡，使养殖水环境持续恶化。这种管理和生产模式与现代生态渔业和无公害水产生产严重违背。如何在水产养殖水质管理中避免或少用对环境有危害的药物，是水产界应该加强研究和推广的重要课题。