1993—1994年对虾暴发病的流行病学研究

研究了山东省的１９９３－１９９４年对虾暴发性流行病的群体病症及其发展，分析了该病的地区，时间、种间分布及个体差异。结果表明，典型的虾池发病历时一周，死亡率达９０％以上；凡虾池密集（〉７０化顷／公里海岸线）、放苗量大（４５－６０万／公顷），投入高（４５，０００－７５，０００元／公顷）的地区发病早、损失大，发病时间主要在６－７月。１９９３年病程短而急，形成一个发病高峰，近似流行病学的偏态分布（对数常态     

天津厚蟹感染对虾杆状病毒及对虾暴发性流行病防治途径的初步研究

本文介绍了天津厚蟹Ｈｅｌｉｃｅ ｔｒｉｄｅｎｓ ｔｉｅｎｓｉｎｅｎｓｉｓ Ｒａｔｈｂｕｎ感染对虾杆状病毒的研究结果，并根据天津厚蟹的分布与发病虾池关系的调查资料，提出为防治对虾暴发性流行病就从防止天津厚及其它底栖、穴居虾蟹类进入虾池入手的意见     

对1994年对虾养殖的几点建议

对１９９４年对虾养殖的几点建议关忠志，李秋（丹东市水产研究所）关键词：对虾养殖，流行病１９９３年一场暴发性对虾流行病蔓及全国，给我国对虾养殖业以沉重的打击。许多地区遭到了灭顶之灾，造成大面积绝产。丹东地区的损失也比较严重。由于虾病的发生，使目前整个养...     

单克隆抗体酶联免疫技术检测对虾皮下及造血组织坏死病的病原及其传播途径

用单克隆抗体ＥＬＩＳＡ技术对１９９４年５月～７月自山东和辽宁采集的虾池和海区材料，包括对虾、浮游生物、小型甲壳类生物、鱼类、底泥及饲料等共１９２个样品进行了对虾暴发性流行病病原ＨＨＮＢＶ的检测。结果表明，对虾中的ＨＨＮＢＶ阳性与虾池发病情况基本相符，用单抗ＥＬＩＳＡ方法可提前２０～４０ｄ对虾池的发病可能性作出预报；桡足类浮游生物的带毒率高于对虾，且其阳性的出现早于对虾，沿岸海区的桡足类浮游生物有较高的阳性率，它可能是对虾暴发性流行病的主要病原携带者；部分地区的卤虫也带有ＨＨＮＢＶ，同时还从糠虾等小型甲壳类生物中检出了病原。     

1993年大连市旅顺口区对虾养殖未发生暴发性流行病原因的初步分析

１９９３年大连市旅顺口区对虾养殖未发生暴发性流行病原因的初步分析严隽箕（辽宁省大连海洋水产研究所１１６０２３）关键词：对虾养殖，暴发性流行病，原因，分析１９９３年４月份以来，全国养殖对虾大面积暴发传染性流行病，首先是广东、福建、继而迅速蔓延到浙江至辽...     

1994年浙江省对虾暴发性流行病病原及传播途径的初步调查

用Ｔ—Ｅ染色、单克隆抗体的ＥＬＩＳＡ现场诊断、组织切片和Ｈ—Ｅ染色和电镜观察等不同方法对１９９４年浙江省乐清和温岭两地区虾池及海区样品进行了现场和实验室检查。结果说明，１９９４年浙江省对虾暴发性流行病实质上是杆状病毒性的皮下及造血组织坏死，病原为ＨＨＮＢＶ。检查到的ＨＰＶ不是这场暴发病的病原。对非对虾类生物和对虾鲜活饲料的单抗ＥＬＩＳＡ检测表明，海区张网饲料可能是１９９４年浙江对虾暴发性流行病的主要传染源，病虾池中除对虾外，其它甲壳类生物在该病的传播上可能也起到一定的作用。这些生物除了可能传播ＨＨＮＢＶ外，还可能传播ＨＰＶ。     

再论对虾养成期虾池的生态效益

再论对虾养成期虾池的生态效益徐启家，赵荣平（山东省海水养殖研究所，青岛２６６００２）１虾病蔓延是生态环境变化的结果虾病是当今国际养虾业的重要研究课题，也是我国养虾业巩固与发展的最大障碍。１９９３年蔓延的暴发性对虾流行病，所造成的损失是难以估量的。近年...     

祖国各地

祖国各地鱼塘虾池搭养肉食性鱼类可以防病海盐县地处杭州湾北岸，属水产养殖业发达的浙江嘉兴地区。目前，全县标准鱼塘的单产一般为每公顷７５００多公斤，虾池单产２２５０公斤左右。１９８９年和１９９３年，该县相继发生了鱼、虾暴发性流行病，且随着水源水质的不断恶...     

中国对虾晚放苗养殖试验

中国对虾晚放苗养殖试验对虾流行病的暴发，除取决于病原、寄主、环境因素外，还与对虾体长、季节、水温有一定的关系。从近几年虾病发生时的一些因素看，水温２３—２５℃，对虾体长６—８ｃｍ，时间在６月上中旬前后。而同样是“白斑病”（头胸甲上有白斑），在养成期传...     

大连普兰店湾养虾示范区虾病诱因初探

１９９４年６－８月,对普兰店湾地区宏升养虾汤发病虾池,未发病虾池,池外海水进行了５面水环境因子的定期跟踪检测。测定发现：普兰店湾海区,在对虾流行病暴发期间,外海水中,约每半月出现１次持续时间为４８小时左右的高氨氮现象。结果表明：虾池纳潮时,内,外海水ＰＨ值相差较大,外海水氨氮严重超标,是诱发已潜伏感染病毒的对虾安病致死的重要环境因子。     

Effects of Stocking Size and Density of Tilapia on Macrobrachium rosenbergii in Polyculture

Studies were conducted to determine the effect of stocking size and density of prawns in polyculture.
In one experiment, postlarval prawns (av. wt. 0.02 g) were stocked in six 0.02 ha earthen ponds at 35,00O/ha. Two ponds were stocked with tilapia fry (av. wt. 0.14 g) and two were stocked with tilapia fingerlings (av. wt. 30.1 g), each at 10,000/ha. Two control ponds had no tilapia. Tilipia stocking size had no effect on prawn growth. Mean weight of prawns after 70 days of culture ranged from a low of 4.5 g when cultured with tilapia fingerlings to a high of 6.6 when cultured in monoculture. Prawn survival was adversely affected by tilapia fry. Average prawn survival in tilapia fry ponds was 65% compared to 75% and 91%, respectively, in tilapia fingerling and monoculture ponds.
In a second experiment, postlarval prawns were stocked in nine 0.02 ha earthen ponds at 40,000/ ha. Six ponds were stocked with 30 g tilapia fingerlings, three at 5,000/ha and three at 15,000/ha. Three control ponds received prawns only. After 100 days of culture, prawn weight ranged from an average of 15.9 g in monoculture ponds to 11.5 g in polyculture ponds. Survival was highest (93.8%) in low density polyculture ponds. Survival was lowest (85.6%) in prawn monoculture ponds. Tilapia reproduction had a negative impact on shrimp production.     

塑料大棚高密度培育早茬虾苗技术研究

塑料大棚充气培育早茬虾苗，每亩放养体长０．７ｃｍ虾苗１０００万尾以上，培育２０天左右出棚，虾苗平均体长１．６２ｃｍ，成活率５０％左右，两年平均每公顷创利２５０５７５元。１９９２年１１月专家鉴定认为，本技术达到国内先进水平。     

脊尾白虾全人工繁育技术初步研究

脊尾白虾是我国沿海地区池塘养殖重要品种,但目前尚未实现全人工繁育,严重制约了产业进一步发展。选取野生脊尾白虾作为亲虾,经过越冬培育、促熟交尾、幼体孵化培育、仔虾选育等手段,进行了脊尾白虾全人工繁育技术研究。试验结果显示,在盐度31.3、水温18.1~26.2℃、pH 8.1条件下,室内越冬脊尾白虾亲虾可成功培养至性腺成熟,并交尾抱卵,平均抱卵率达70%,平均孵化率为61.02%。幼体最佳培育密度20尾/L,仔虾适宜养殖密度0.13~0.53尾/L,培育至2cm时存活率可达80%,继续培育3个月后发育至性成熟。一年可繁殖2~3代。在此基础上建立了脊尾白虾近交家系,现已培育至第6代,各家系繁殖力、生长速度和存活率均未出现近交衰退现象。本研究初步解决了脊尾白虾室内全人工繁育技术,并为试验动物培育奠定了良好的技术基础。     

提高海湾扇贝虾池保苗成活率技术研究

利用６５亩虾池进行提高海湾扇贝保苗成活率技术研究，入池稚贝２．１亿粒，经４３天暂养，出池商品苗９７２０万粒，成活率达４６．３％，纯益３５．８４万元。而海上保苗成活率仅为１０％左右。１９９４年２月，专家鉴定认为，本研究居国内先进水平。     

Temporal Variation in Egg and Larval Productivity of Eyestalk Ablated Spawners of the Prawn Penaeus monodon from Cook Bay, Australia

This paper reports on the variability in spawner performance and viability of the eggs and larvae of Penueus monodon from a single geographical region (Cook Bay, Australia). Data is presented from seven separate experiments spawning eyestalk ablated P. monodon conducted between Sep tember 1992 and July 1994. These experiments used 200 spawners from which 290 spawns were assayed. Total egg and larval (Nauplius, and ha,) production values per prawn were calculated and were significantly different ( P < 0.05) between experiments. Spawner weight and number of spawns per prawn also varied significantly between experiments and, although these factors afiected egg and larval productivity, they accounted for only a small percentage of the observed variability. The cause of this variation is unknown but it may be due to differences in the age of the spawners and to seasonal environmental effects. The variation in reproductive success of wildcaught spawners probably reflects differences in overall condition of the spawners and/or their nutritional status at different times. Understanding the causes of variation in productivity is important if hatcheries are to improve the reliability of supply of larvae for the prawn farming industry.     

对虾病的防治对策研究

本文报道对虾病对浙江１９９３年养殖造成的严重经济损失，虾病情调查。现场药物和水质治理的试验结果，总结研究出几条防治虾病的对策。     

A Comparison of Two Feeding Technologies in Freshwater Prawns,Macrobrachium rosenbergii,Raised at High Biomass Densities in Temperate Ponds

ABSTRACT

Recent developments in prawn production technologies (i.e., added substrate, increased stocking densities, size grading, and increased feed rates) have increased production rates from 900-1,000 kg/ha to over 2,500 kg/ha. While prawn can receive substantial nutritional benefit from natural foods at the lower biomass densities, at higher production rates prawn are likely to be more dependent on prepared diets. To ensure that maximum production is being achieved by these new production technologies, production rates must not be nutritionally constrained. This study was conducted to compare the current recommended technology of phase feeding of different quality feedstuffs to prawns of different sizes with the feeding of a high-quality penaeid diet throughout the production season. Two treatments were evaluated: Treatment 1 was phase feeding (current technology-control) where prawns were fed unpelleted distillers' grains with solubles (DDGS) for the first four weeks, then a 28%-protein prawn diet for weeks 5-12, and finally a 40%-protein penaeid diet for weeks 13-16. In Treatment 2, prawn were fed the 40%-protein penaeid diet throughout the entire production period. Feeding rates in both treatments were based upon a feeding table. Three 0.04 ha ponds were used for each treatment. All ponds were stocked at 59,280 juveniles/ha and were provided with artificial substrate in the form of a polyethylene “safety fence” oriented vertically to increase available surface area by 50%. After 106 culture days, no significant differences (P >0.05) were observed between treatments in terms of yield, average individual weight, food conversion ratio (FCR), or survival, which averaged 2,575 kg/ha, 46 g, 2.3, and 94%, respectively, overall. Due to the higher cost of the penaeid diet (US$0.84/kg), feeding costs for the penaeid diet treatment (Treatment 2) were 38% higher than those for Treatment 1. No benefit to using higher protein diets during the first 12 weeks of prawn pond production was observed.     

Modelling the dispersal of larval Japanese sardine, Sardinops melanostictus, by the Kuroshio Current in 1993 and 1994

Acoustic Doppler current profiler (ADCP) data collected during routine monitoring surveys of the distribution and abundance of Japanese sardine larvae ( Sardinops melanostictus ) off the Pacific coast of Japan in February 1993 and 1994 were used to construct stationary average flowfields for three levels in the upper 100 m in each year. No large-scale meanders in the path of the Kuroshio Current were present in either year, but the axis of the current was closer to the coast in 1993 than in 1994. The flowfields were used to drive a particle-tracking model representing the dispersal of sardine eggs and larvae. Particles were released in accordance with the observed distribution of eggs, and their positions tracked for up to 40 days. In 1993, the model indicated that ≈ 50% of the egg production was carried north-eastwards out of the survey area into the area of the NW Pacific referred to as the Kuroshio Extension Zone. In contrast, only 5% of the egg production was exported to the Extension Zone in 1994, the remainder being retained in Japanese coastal waters. The consequences of the different dispersal patterns are discussed in relation to subsequent recruitment to the sardine stock. Based on commercial catch data, survival of the 1993 year class was 15% of that for the 1994 class. Hence, the results indicate that export of larvae to the Kuroshio Extension cannot in itself lead to successful recruitment.