美洲地区对虾TSV、IHHNV、WSSV和YHV病毒的流行现状、诊断方法及防治对策 (二)

２．托拉综合症病毒（ＴＳＶ） 根据其病毒颗粒结构（无囊膜的二十面体，３０ｎｍ直径，带胞质复制体，一个单链ＲＮＡ基因组），ＴＳＶ被归类为细小核糖核酸病毒 （ｐｉｃｏｒｖｉｒｕｓ）。 ＴＳＶ于１９９２年首次发现于瓜亚基尔（Ｇｕａｙｏｇｕｉｌ）湾托拉河口附近的对虾养殖场，造成池塘养殖的南美白对虾幼虾６０％－９０％死亡的灾难性损失。接着作为一种严重的病害，ＴＳＶ很快在拉美国家和美国的部分养虾地区流行蔓延。流行病学和实验室研究以及从厄瓜多尔向外的传播都表明，ＴＳＶ是一种病毒性病原，而且在美洲的南美白对虾、蓝…     

春季小龙虾白斑综合征病毒病防治介绍

白斑综合征病毒（WSSV），1992年首次在台湾对虾养殖中被发现，一度给对虾养殖业造成巨大损失，直到今天依然是对虾养殖中需要重点防范的主要病害之一。2007年5月江苏省首次发现该病毒在养殖克氏原螯虾中感染流行，并造成克氏原螯虾的批量死亡。2007年全省发病面积近6000×667m2，发病塘口死亡率在5％-20％；至2008年底，全省发病面积已达8万亩。     

中国对虾肝胰腺细小样病毒病发病成因及综合防治技术

北方地区对虾养殖生产常因病毒侵袭而爆发传染性疾病，除危害最甚的对虾白斑病毒病外，近年来中国对虾肝胰腺细小样病毒病的发病率有逐年上升的趋势。该病病程缓慢且流行时间长，可造成对虾养成率低等恶果，发病严重的虾池可减产５０％－７０％以上，严重影响养虾效益，为研究探索防治该病的有效方法，今年我们采取综合措施进行病害防治，取得了较为理想的效果。 一、发病虾池状况 １．养殖面积：４亩； ２．养殖密度：１２万尾／亩； ３．养殖品种：中国对虾； ４．投苗日期；２００１年５月５日； ５．池塘位置：天津汉沽区杨家泊镇。 二…     

饲料中必需脂肪酸对中国对虾体内必需脂肪酸含量的影响

用正交设计法设计亚油酸（１８∶２ｎ－６）、亚麻酸（１８∶３ｎ－３）、二十碳五烯酸（２０∶５ｎ－３）和二十二碳六烯酸（２２∶６ｎ－３）３因素、３水平饲喂中国对虾试验,结果表明,对虾体内４种必需脂肪酸（ＥＦＡ）含量随饲料中４种必需脂肪酸含量增加而增加。当饲料中亚麻酸、二十碳五烯酸和二十二碳六烯酸含量分别为０．８４％～１．１０％、０．２１％～０．４８％和０．３７％～０７４％时,养殖对虾与野生虾体内这３种必需脂肪酸含量接近。由于饲料中亚油酸含量较高,所以养殖虾体内亚油酸含量高于野生虾。     

南美白对虾如何告别红体病

红体病症状红体病，专业上又称桃拉（TAURA）综合症，由桃拉病毒引起，该病的暴发有以下规律：通常在气温骤升或骤降时出现；养殖对虾的发病时间在３０～６０天；发病的对虾规格在５～９厘米；病虾池水色浓，透明度低，仅在２０厘米以内，pH值高于９，氨氮含量则在０．５毫克／升以上。该病的发生蔓延时间较长，一般较少引起急速的大规模死亡现象，其早期症状表现为：对虾群体常出现环游现象，虾体无明显改变，仅尾扇出现蓝色斑点或有少量微小的白色斑点；肉眼分不出肝脏和心脏（正常对虾肉眼可分清肝脏和心脏），只能看出肝脏肿大或变淡…     

黑鲷、对虾、缢蛏生态混养技术

鱼虾贝生态养殖是优化养虾池塘生态结构的一种有效途径。近年来 ,我们在乐清湾沿岸虾塘实施千余亩黑鲷、对虾、缢蛏（或泥蚶）生态混养技术示范 ,取得了平均亩产９～１２厘米体长对虾５０公斤、黑鲷２０公斤、缢蛏５００公斤或泥蚶２５０公斤的产量 ,每亩毛利润６０００元。现将其生态混养技术介绍如下 :一、虾塘选择与改造沿岸进排水比较方便的常规虾塘均可以作为生态混养场所 ,面积以５～３０亩大小为宜。待上年虾塘养殖产品收获完毕 ,就可对池底进行翻耕、曝晒、耙平 ,并按黑鲷、对虾、缢蛏（或泥蚶）生态混养对养殖生态地形的要求改造常…     

对虾池不同综合养殖系统效率和效益的比较研究

利用５０个５．０×５．０×１．８ｍ陆基围隔研究了中国对虾与台湾红罗非鱼、海湾扇贝和缢蛏投饵或施肥混养及鲈鱼与中国对虾和台湾红罗非鱼混养最佳结构的生态效率、生产效果和经济效益。结果表明,几种综合养殖系统最佳结构下各种养殖对象对Ｎ的绝对利用率由高至低依次为：鲈鱼－对虾－罗非鱼（３０．９１％）＞对虾－海湾扇贝（２１．０９％）＞对虾－罗非鱼施肥混养（２０．１２％）＞对虾－罗非鱼投饵混养（１７．８１％）＞对虾－缢蛏（１６．９３％）＞单养对虾（１１．５２％）;对Ｐ的绝对利用率由高至低依次为：对虾－缢蛏（１６．０８％）＞鲈鱼－对虾－罗非鱼（１２．８３％）＞对虾－罗非鱼投饵混养（１２．６３％）＞单养对虾（１０．８８％）＞对虾－海湾扇贝（６．０１％）＞对虾－罗非鱼施肥混养（４．０４％）;其产出投入比由高至低依次为：对虾－罗非鱼投饵混养（１．９９）＞对虾－罗非鱼施肥混养（１．９８）＞对虾－海湾扇贝（１．５３）＞单养对虾（１．３８）＞鲈鱼－对虾－罗非鱼（１．３０）＞对虾－缢蛏（１．２３）。     

1994—1995年福建养殖对虾暴发病流行病学调查

本文报道了１９９４－１９９５年福建沿海主要对虾养殖区养殖的日本对虾,斑节对虾和长毛对虾暴发病流行情况,明确其发病时间,发病特点,流行牲和虾病暴发的主要原因有四方面：（１）病毒感染;（２）病毒与细菌合并感染;（３）海区水环境污染;（４）营养不良滥用药物使对虾低抗力降低。     

中国对虾（Penaeus orientalis Kishinouye）的几种必需脂肪酸营养价值的比较研究

用四种试验饵料，其中分别含有１％高纯度的ω－３及ω－６不饱和脂肪酸（亚油酸Ｃ１８∶２ω６、亚麻酸Ｃ１８∶３ω３、花生四烯酸Ｃ２０∶４ω６、二十二碳六烯酸Ｃ２２∶６ω，ＤＨＡ）以及一种对照饵料含有５％棕榈酸Ｃ１６∶０和油酸Ｃ１８∶１ω９混合物对中国对虾（ＰｅｎａｅｕｓｏｒｉｅｎｔａｌｉｓＫｉｓｈｉｎｏｕｙｅ）幼虾进行了为期３２天的投喂试验，从成活率、蜕皮次数及增重等实验结果可见二十二碳六烯酸（ＤＨＡ）对中国对虾幼虾具有最高的营养价值。同时，对海捕和人工养殖的中国对虾的脂肪酸组成进行了比较，两者都含有大量的ω－３系列的高度不饱和脂肪酸；但是与海捕虾相比较，人工养殖对虾的ＤＨＡ含量较低，而亚油酸含量较高。上列结果表明在对虾饵料中补充富含ＤＨＡ的脂肪源将有效地促进对虾增产。     

中国对虾疾病研究进展及养殖中应采取的措施

近几年来,由于对虾养殖大面积暴发虾病,致使养虾业遭受到严重的打击。为此,农业部和中国科协组织全国各地的科研院所,对养虾的疾病防治问题进行联合攻关。经过两年来全国对虾病方面研究,在以下几个方面取得了成绩和进展：l．基本查清了1993年以来全国暴发流行性疾病的病原生物及其形态结构和组织病理。全国不同地区的研究表明,这次流行的虾病是一种不形成包涵体的杆状病毒,不同地区病毒大小和形态上虽有一定差异,但研究结果分析表明,这种杆状病毒可能是同一种病毒,病原生物研究结果表明,除几种病毒和细菌（主要是弧菌）外,还发…     

Anguilla huangi Teng, Lin, and Tzeng, 2009, is a junior synonym of Anguilla luzonensis Watanabe, Aoyama, and Tsukamoto, 2009

Anguilla luzonensis and A. huangi were each described in 2009 using eels obtained from northern Luzon Island. We examined the taxonomic status of these two groups of eels using morphological and molecular genetic characters. There were no significant differences in two vertebrae counts between eels of A. luzonensis and A. huangi. Mitochondrial 16S ribosomal RNA and cytochrome b genes sequences were obtained and compared among 28 specimens of A. luzonensis, the holotypes of A. luzonensis and A. huangi, and one specimen of the other 15 anguillid species. The specimens of A. luzonensis exhibited almost identical sequences, including the holotype, with only a few site differences, and the genetic difference between the holotypes of A. luzonensis and A. huangi was within the range of differences of specimens of A. luzonensis. The other anguillid species were genetically very different from A. luzonensis and A. huangi, although A. interioris is a closely related species. It is clear that A. luzonensis and A. huangi are the same species, and according to the principle of priority in zoological nomenclature, A. luzonensis Watanabe, Aoyama, and Tsukamoto, 2009 is the valid species name, and A. huangi Teng, Lin, and Tzeng, 2009 is a junior synonym of A. luzonensis.     

Atlantic Fisheries Technological Conference,Moncton, NB,August 21, 1995

No abstract available for this article.     

Age,growth, maturity and the overfishing of the iconic sciaenid,Argyrosomus japonicus,in south-eastern,Australia

Mulloway (Argyrosomus japonicus) occur in estuarine and coastal waters surrounding Australia, Africa, India, Pakistan, China, Korea and Japan, where they are important in fisheries. This study identified that mulloway in south-eastern Australia had similar growth rates, but matured at smaller lengths and younger ages, to those in South Africa and Western Australia. Growth of both sexes was similar to about 5 years, after which females grew faster and attained a greater maximum length than males. Female mulloway matured at 4–5 years of age with a L₅₀ of 68 cm, whereas males matured at 2–3 years of age with a L₅₀ of 51 cm. The commercial fishery in New South Wales was characterised by declining catches and a reduction in the proportion of mulloway of mature lengths in landings. During 2002–2005 commercial landings were dominated (83%) by fish within 15 cm of the current minimum legal total length of 45 cm and aged 2 and 3 years (>80%), even though mulloway can attain lengths of 200 cm and live >30 years. Estimates of the rates of instantaneous total mortality ranged between 0.34 and 0.45, whilst the rate of instantaneous natural mortality (M) was estimated to be approximately 0.12. Yield-per-recruit analyses indicated that mulloway in New South Wales are being growth overfished and substantial increases in yield could be achieved by increasing the length at first harvest. Values of the spawning potential ratio were below 0.2 under a range of mortality estimates, suggesting that mulloway are at risk of recruitment overfishing. These results suggest that the spawning stock of mulloway in south-eastern Australia has been depleted and that remedial management action is required to protect this iconic species.     

Effects of Mosquitofish,Gambusia affinis,on Channel Catfish,Ictalurus puncatatus,Production Ponds

Mosquitofish, Gambusia sp., have been spread throughout the world to biologically control mosquitoes. However, the fish has gained a reputation as an invasive species and has been implicated in displacing native aquatic species. Gambusia affinis are native to the southeastern United States and commonly occur in commercial channel catfish, Ictalurus punctatus, production ponds. We investigated effects of mosquitofish presence on zooplankton populations, water quality, disease occurrence, and fish production in experimental ponds. There were no differences between ponds with or without mosquitofish in numbers of calanoid copepods, cyclopoid copepods, total copepods, Bosmina sp., Ceriodaphnia sp., Moina sp., Daphnia sp., or total cladocerans. There were also no differences in copepod and cladoceran sizes. Copepod nauplii were more numerous during the summer months in ponds with mosquitofish. There were no differences in water quality variables (soluble reactive phosphorus, nitrate, nitrite, ammonia, total nitrogen, total phosphorus, pH) or phytoplankton density between ponds stocked with and without mosquitofish. Catfish production and disease occurrence were also similar between ponds with and without mosquitofish. Although mosquitofish may cause problems when stocked outside their native range, there does not appear to be any adverse effects of mosquitofish presence in catfish production ponds.     

Surface disinfection of Pacific threadfin, Polydactylus sexfilis, and amberjack, Seriola rivoliana, eggs

The effects of exposing the eggs of Pacific threadfin and amberjack eggs (AEs) to different concentrations of hydrogen peroxide for 5 min on hatch rate and survival were assessed in a series of experiments using a petri dish model rearing system. Despite significant inter‐batch variation in hatch rate, it was shown that eggs of both species could be safely exposed to up to 11 340 mg L⁻¹ H₂O₂ for 5 min. Exposure to 34 230 mg L⁻¹ H₂O₂ for 5 min was shown to be lethal to AEs at a late stage of development. In two further experiments, it was demonstrated that Pacific threadfin eggs were resistant to all tested concentrations of a range of polyvinylpyrrolidone iodine (PVP‐I) concentrations and contact times (up to 1000 mg L⁻¹ PVP‐I for 10 min). The level of bacteria adhering to the eggs of both species was highly variable. Where eggs were heavily colonized (>10⁴ cfu egg⁻¹), hydrogen peroxide concentrations of at least 11 340 mg L⁻¹, or PVP‐I concentrations higher than 500 mg L⁻¹ for 10 min, were required for effective sterilization. In less colonized batches, rinsing in sterile seawater or exposure to lower (550 mg L⁻¹) concentrations of H₂O₂ was sufficient to result in high apparent levels of surface sterility (<1 cfu egg⁻¹).     

Compositional differences,antioxidant activity,angiotensin-converting enzyme inhibition,and sensory characteristics of kamaboko fermented in wheat,rice, brown rice,and soybean koji

Fisheries Science - Fermentation of kamaboko in koji with wheat (KW), rice (KR), brown rice (KB), or soybean (KS) was performed by simulation of tofuyo processing. Moisture and protein content...     

Sperm Motilities in Waigieu Seaperch,Psammoperca waigiensis: Effects of Various Dilutions,pH, Temperature,Osmolality, and Cations

The objectives of this study were to evaluate the effects of varying dilutions, pH, temperature, osmolality, and cations on sperm motility parameters in waigieu seaperch, Psammoperca waigiensis. The maximum velocity of average in path (VAP), percentage of motile cells (MOT), and duration of sperm motility (DSM) were observed when semen was diluted in artificial seawater (ASW) at a ratio of 1:100 (144.9 ± 0.6 µm/sec, 95.6 ± 0.4%, and 230.3 ± 2.3 sec, respectively), at 30 C (142.0 ± 0.6 µm/sec, 93.6 ± 0.4%, and 238.3 ± 0.9 sec, respectively), and pH 8 (144.8 ± 0.6 µm/sec, 93.3 ± 0.4%, and 234.0 ± 1.5 sec, respectively). Maximum VAP, MOT, and DSM were obtained in each solution containing 0.6 M NaCl (143.8 ± 1.0 µm/sec, 91.3 ± 2.0%, and 230.6 ± 4.2 sec, respectively), 0.6 M KCl (135.1 ± 3.1 µm/sec, 91.1 ± 3.1%, and 230.3 ± 3.7sec, respectively), 0.2M CaCl₂ (105.3 ± 4.7μm/sec, 47.9 ± 2.7%, and 120.7 ± 1.3 sec, respectively), 0.2 M MgCl₂ (107.3 ± 3.0 m/s, 42.1 ± 3.3%, and 120.3 ± 4.8 sec, respectively), and osmolality of 400 mOsm/kg (145.1 ± 2.5 µm/sec, 93.0 ± 2.1%, and 346.5 ± 4.4s, respectively). We used these mediums as artificial insemination media for fertilizing matured eggs. The results showed that the fertilization and hatching rates in 0.6 M NaCl (75.3 ± 0.6% and 57.0 ± 2.4%, respectively), ASW (70.8 ± 1.2% and 51.2 ± 1.8%, respectively), or 400 mOsm/kg (72.9 ± 1.8% and 55.3 ± 1.6%, respectively) were higher than that in seawater (63.9 ± 1.2% and 39.2 ± 3.9%, respectively). In conclusion, using 0.6 M NaCl, ASW, or 400 mOsm/kg as an artificial insemination medium is effective for fertilizing of waigieu seaperch.     

Operating parameters affecting biofloc technology: carbon source,carbon/nitrogen ratio,feeding regime,stocking density,salinity, aeration,and microbial community manipulation

Aquaculture International - The world population continues to increase day by day. Therefore, aquaculture needs to grow in order to response the need for protein foods and to cope with the problem...