氟苯尼考在水产养殖中的应用

饲料级抗菌素“氟苯尼考”(florfenicd,简称FFC)已经在水产养殖动物上广泛应用于防止细菌性疾病,如在日本的黄鱼、真鲷、虹鳟、银鲑、竹荚鱼,韩国的黄鱼、鳗鱼和英国的大西洋鳟上已批准使用。“氟苯尼考”是专门设计在水产饲料上使用的抗生素药之一,目前在更多养殖品种上的研究     

氟苯尼考在水产养殖中的应用

简述氟苯尼考在水产养殖中的抗菌活性和耐药性,以及水产动物体内氟苯尼考的药代动力学,分析氟苯尼考对动物机体的急性毒性、免疫抑制,以及对水环境中的微生物及昆虫等造成影响.指出,与较早期的酰胺醇类药物相比,氟苯尼考具有高效、低毒的优点,但随着长时间的使用,一些致病菌对其逐渐产生了耐药性.提出,在水产养殖中,要合理规范使用氟苯...     

氟苯尼考--水产养殖业中氯霉素的最新替代产品

1　氯霉素的缺点在水产养殖业中,水产动物的疾病经常发生,特别是细菌性疾病对水产动物的危害仍非常严重。病害的发生所造成的经济损失每年达上百亿元。给养殖业带来了巨大损失。以前,预防和治疗这类疾病时常用氯霉素等抗菌药,但氯霉素易产生耐药性,其致再生障碍性贫血的缺点,使我国水产品出口屡遭限制和封杀。美国及欧盟于1 996年,我国于2 0 0 2年3月,就明令禁止食用动物使用氯霉素。2　氟苯尼考的抗菌机理它既可选择性地作用细菌70S核蛋白体的受体,从而改变和干扰细菌肽酰转移酶的功能,又能与细菌核糖体上的“5 0S亚基”紧密结合,阻碍肽酰…     

氟苯尼考的药效学及其在水产动物中的代谢动力学研究进展

氟苯尼考具有很强的抗菌活性,对大多数革兰氏阳性菌及阴性菌都有作用,在水产养殖上有广泛应用。本文综述了氟苯尼考在水产动物中的药效学、药物动力学及残留消除规律的研究进展,以期为氟苯尼考在水产病害防治中的科学性和规范性应用提供思路,促进我国水产品的安全与水产养殖的可持续发展。     

世界水产养殖现状

本文作者搜集了大量资料,对目前世界水产养殖现状作全面概述。对我国研究世界水产养殖发展战略,具有重要的参考作用。     

有机水产养殖探讨

随着现代水产养殖的快速发展,水产养殖对环境的破坏也日显突出。养殖过程中使用的化学品和药剂带来了食品安全的风险问题。有机水产养殖是一种在生态上合理的可持续水产品生产系统,满足了人们对生态环境保护和食品质量安全的需求。介绍了与常规水产养殖有关的环境污染和公众健康问题,阐述了有机水产养殖的概念、与常规水产养殖的区别、优越性以及有机水产养殖标准的由来,探讨了当前有机水产养殖面临的挑战。     

Depletion of florfenicol amine in tilapia (Oreochromis sp.) maintained in a recirculating aquaculture system following Aquaflor®‐medicated feed therapy

Aquaflor^® [50% w w^?1 florfenicol (FFC)], is approved for use in freshwater‐reared warmwater finfish which include tilapia Oreochromis spp. in the United States to control mortality from Streptococcus iniae. The depletion of florfenicol amine (FFA), the marker residue of FFC, was evaluated after feeding FFC‐medicated feed to deliver a nominal 20 mg FFC kg^?1 BW d^?1 dose (1.33× the label use of 15 mg FFC kg^?1 BW d^?1) to Nile tilapia O. niloticus and hybrid tilapia O. niloticus × O. aureus held in a recirculating aquaculture system (RAS) at production‐scale holding densities. Florfenicol amine concentrations were determined in fillets taken from 10 fish before dosing and from 20 fish at nine time points after dosing (from 1 to 240 h post‐dosing). Water samples were assayed for FFC before, during and after the dosing period. Parameters monitored included daily feed consumption and biofilter function (levels of ammonia, nitrite and nitrate). Mean fillet FFA concentration decreased from 13.77 μg g^?1 at 1‐h post dosing to 0.39 μg g^?1 at 240‐h post dosing. Water FFC concentration decreased from a maximum of 1400 ng mL^?1 at 1 day post‐dosing to 847 ng mL^?1 at 240 h post‐dosing. There were no adverse effects noted on fish, feed consumption or biofilter function associated with FFC‐medicated feed administration to tilapia.     

氟苯尼考在罗非鱼体内的药物动力学

氟苯尼考属于动物专用的氯霉素类抗生素,罗非鱼是我国主要养殖品种之一,开展氟苯尼考在罗非鱼体内的药物动力学研究对正确用药具有指导意义和实用价值。在22%水温条件下,采用药饵给药,剂量为10mg·kg~(-1)体重,研究氟苯尼考在罗非鱼体内的药物动力学。采用非房室模型统计矩原理计算药物动力学参数,血浆和肌肉峰药物浓度(C_(max))分别为4.46μg·mL~(-1)和6.88μg·g~(-1),达峰时间(T_(max))均为12 h,血浆和肌肉的药物浓度-时间曲线下面积(AUC)分别为86.68 h·μg·mL~(-1)和112.71 h·μg·g~(-1),消除半衰期(T_(1/2β))分别为10.03和10_97h。本实验条件下,血浆和肌肉中药物维持在有效治疗浓度(MIC 取0.8μg·mL~(-1))以上的时间均在40 h 以上。在给药后168 h,血浆中药物浓度为0.04μg·mL~(-1),而肌肉中已经检测不到氟苯尼考(检出限为0.03μg·g~(-1))。试验数据表明,氟苯尼考不仅治疗效果良好,而且在罗非鱼体内消除快、残留少,具有良好的应有价值。     

Rating fixed film nitrifying biofilters used in recirculating aquaculture systems

Predicting the performance of biofilters is an engineering challenge that is critical to both designers and managers. The task is complicated by the wide variety of water quality expectations and environmental conditions displayed by a recirculating aquaculture system (RAS). A myriad of biofilters designs have been generated reflecting approaches of engineers attempting to maximize specific surface area and oxygen transfer within the context of a biofilm management strategy. A rating strategy is presented for biofilters to facilitate the identification of appropriate matches between biofiltration formats and RAS applications. As a foundation, a previously proposed RAS classification system based upon salinity, temperature and trophic levels is upgraded to create 17 systems classifications. A biofilter classification system identifies seven combinations of trophic level and pH which should be sufficient to serve the RAS demands. Temperature and salinity are neglected as a means of simplifying the approach. An experimental methodology based upon chemical feeds is proposed to represent the steady-state RAS performance of the biofilters. Data is summarized by linear analysis of filter performance for concentration ranges below 1.0 g TAN m⁻³ and simple averaging is proposed for higher trophic levels. Input from the aquacultural engineering community and RAS aquaculturists is required to further refine the approach prior to endorsement.     

Pharmacokinetics of florfenicol and behaviour of its metabolite florfenicol amine in orange‐spotted grouper (Epinephelus coioides) after oral administration

Pharmacokinetics and elimination of florfenicol and florfenicol amine in grouper held in sea water at 23.3 ± 0.8 °C were studied using HPLC method after they were given a single peroral dose of florfenicol at 24 mg kg^?1 body weight. Florfenicol was rapidly absorbed from intestine and distributed extensively to all the tissues examined. The maximum concentrations (C_max, μg g^?1 or μg mL^?1) in plasma and tissues were observed at 2–6 h (the time to reach maximum concentration, T_max) except for bile (T_max = 24 h) and were in the order of intestine (52.02 ± 25.07) > bile (49.41 ± 28.16) > gill (45.12 ± 11.10) > plasma (28.28 ± 5.43) > liver (21.97 ± 12.08) > muscle (21.63 ± 6.12) > kidney (20.88 ± 11.28) > skin (19.10 ± 5.88). The drug distribution level was higher in plasma than in extravascular tissues except for bile, based on the ratios of the area under concentration–time curve between tissue and plasma (AUC_{tissue/plasma}). The elimination of florfenicol was rapid in fish, and the corresponding half‐lives (T_1/2β) in the order of magnitude were bile (13.92 h) > muscle or liver (12.31 h) > skin (11.77 h) > plasma (11.57) > gill (11.04 h) > intestine (10.55 h) > kidney (10.05 h). The delayed T_max, lower C_max and longer T_1/2β for florfenicol amine compared with florfenicol were measured in grouper.     

氟苯尼考及其代谢物氟苯尼考胺在斑点叉尾鮰体内的残留消除规律

研究不同水温(18℃和28℃)下,氟苯尼考(Florfenicol,FF)及其代谢物氟苯尼考胺(Florfenicol Amine,FFA)在斑点叉尾体内残留消除规律。以含氟苯尼考4 g/kg的饲料按10 mg/kg鱼体质量连续强饲斑点叉尾(Ictalurus puncta-tus)3 d,于停药后第1天2、天3、天5、天7、天9、天分别将斑点叉尾处死后取肌肉、肝脏、皮肤、肾脏4种组织。采用反相高效液相色谱紫外检测法测定斑点叉尾组织中氟苯尼考及其代谢物氟苯尼考胺。结果表明,不同水温下相同组织,相同水温下不同组织中氟苯尼考及其代谢物氟苯尼考胺的消除速率快慢不一(差异显著P<0.05)。氟苯尼考和氟苯尼考胺之和作为标示残留物的指示值,高水温时标示残留物(总量)在斑点叉尾体内消除的更快。与其他组织相比标示残留物(总量)在肾脏中的消除最慢,因此,建议将肾脏作为标示残留物(总量)在斑点叉尾体内残留的靶组织。在18℃和28℃时,若规定标示残留物(总量)在肾脏中以300μg/kg为最高残留限量(maximum residue limit,MRL),建议休药期分别为234℃.d和224℃.d。本研究旨为不同水温条件下制定该药的休药期提供理论依据。     

Shellfish aquaculture in Thailand

Abstract

Shellfish have been farmed in Thailand for over 100 years, and during this time, traditional culture techniques have gradually given way to more sophisticated and capital intensive methods. Farmed shellfish production increased from 73,976 to 138,202 metric tonnes between 1988 and 2000. Major species currently under cultivation include the green mussel Perna viridis, the blood cockle Anadara granosa, and three species of oyster (Saccostrea cucullata, Crassostrea belcheri, and Crassostrea iredalei). The horse mussel Arcuatula arcuatula is also produced in limited amounts for animal feed, and gastropods such as the abalone Haliotis asinina and the spotted babylon Babylonia areolata are in the initial phases of commercialization. With the globalization of fisheries commodity markets, the Thai shellfish sector is slowly implementing more rigorous management and certification processes. These procedures are required to access European, American and Japanese markets, and would also serve to decrease the risk of gastrointestinal disease for local consumers.     

Depletion study and estimation of withdrawal periods for florfenicol and florfenicol amine in pacu (Piaractus mesopotamicus)

The intensive production of farmed fish is at a global all‐time high, and the control of bacteria proliferation in fish farms requires the frequent use of antimicrobials. This practice raises important environmental concerns related to the emergence of antimicrobial‐resistant bacteria strains. Only a few antimicrobial drugs have been approved for use in aquaculture, one of which is florfenicol. This work studies the depletion and withdrawal period of florfenicol and its main metabolite, florfenicol amine, in pacu (Piaractus mesopotamicus), a neotropical characin widely farmed in the southern hemisphere. Juvenile pacu (average weight of 724 g) were stocked in a closed‐loop laboratory system with controlled water temperature (25.8°C), and were fed for 10 consecutive days with a diet containing an intended dose of 10 mg/florfenicol per kg bw. Muscle and skin tissues were collected at 1, 3, 6, 8, 10, 12 and 16 days post‐treatment, and florfenicol and florfenicol amine were quantified using a validated ultra‐high performance liquid chromatography‐tandem mass spectrometry (UPLC‐MS/MS) method. The limits of quantitation for florfenicol and florfenicol amine were 10 ng/g in muscle and 50 ng/g in skin. Considering a maximum residue limit of 1000 ng/g for the sum of florfenicol and florfenicol amine in muscle with skin in natural proportions a withdrawal period of 5 days (water temperature 25.8°C) or 129 degree days was calculated on the basis of the upper limit of the one‐sided 95% confidence interval for the 99^th percentile derived from the residue depletion study.     

养殖工船系统构建与总体技术探讨

随着社会经济发展,开发海洋生物资源是国家战略及必然趋势。养殖工船是发展深远海养殖工程的核心装备之一,深入研究养殖工船,大力发展深远海养殖,具有较高的经济价值和社会价值。该文从装备技术发展面临的问题出发,以动力系统、系泊系统、养殖系统、物流系统及加工系统的总布置为基础,兼顾安全性、经济性及环保性,将商用运输船设计方法和养殖技术要求有机结合在一起,初步探讨了构建深远海养殖工船系统和总体技术框架。提出了重点关注和研究的技术方向,以期实现船舶和养殖行业的联合技术攻关,早日形成产业指南和设计规程,指导后续养殖工船设计。结合中国强大的船舶海工制造能力,完成养殖工船的批量建设,实现未来规模化深远海养殖。     

国内外工厂化循环水养殖研究进展

工厂化循环水养殖模式是一种新型的高效养殖模式, 以养殖用水净化后循环利用为核心特征, 节电、节水、节地, 符合当前国家提出的循环经济、节能减排、转变经济增长方式的战略需求。本文以循环水养殖模式应用实践为主线, 结合近几年养殖模式的科学研究和产业发展, 围绕养殖管理与应用, 分别对水循环系统对化学物质的承载力、水循环率、主要养殖种类、养殖效果和最适养殖密度等运营管理环节进行了总结和探讨, 为今后建立适用于中国国情的工厂化循环水养殖模式管理标准提供参考。