悬浮物对中国明对虾幼体急性毒性效应研究

本文通过室内模拟试验研究水体中悬浮物对中国明对虾不同幼体期生长的急性毒性效应。以无节幼体、溞状幼体、糠虾幼体和仔虾为试验生物,设置不同悬浮物质量浓度的试验组,并对死亡幼体进行计数,建立死亡率和悬浮物质量浓度对数的响应关系,求解中国明对虾幼体96h半致死质量浓度值。试验结果表明,悬浮物对中国明对虾4个时期幼体的生长均具有显著影响(P0.01),悬浮物质量浓度与幼体死亡率呈线性关系,死亡率随悬浮物质量浓度的增加而升高;无节幼体、溞状幼体、糠虾幼体、仔虾的96h半致死质量浓度分别为741.31、457.09、912.02mg/L和1023.29mg/L,线性相关系数分别为0.9771、0.9753、0.9859、0.9798。4种幼体中溞状幼体受悬浮物影响最大,仔虾受影响最小。     

从中国对虾不同生长阶段的营养需求看投饵变化的科学合理性

通过从中国对虾无节幼体期、蚤状幼体期、糠虾幼体期、仔虾期、养成期不同生长阶段的营养需求,看生产过程中投饵发生变化的科学合理性,进而为中国对虾的健康科学投饵养殖提出几点建议。     

复方三氯异氰尿酸对斑节对虾幼体的毒性试验

用静水试验法研究了复方三氯异氰尿酸对斑节对虾幼体的急性毒性.试验设8个浓度组和1个对照组:0、0.5、1.0、1.5、2.0、2.5、3.0、3.5和4.0(×10-6)每组3个平行.结果表明,24hLC50、48hLC50和安全浓度(×10-6)分别是无节幼体:1.58、1.35和0.29;蚤状幼体:1.71、1.24和0.2;糠虾幼体:2.2、1.46和0.24;仔虾:3.23、2.62和0.53.幼体对试验药物的忍受力由大到小分别是仔虾、无节幼体、糠虾幼体和蚤状幼体.试验结果可为斑节对虾育苗安全用药提供参考.     

弧菌对斑节对虾虾苗致病性的研究

本文用6种弧菌对斑节对虾虾苗进行致病性试验。发现6种弧菌对各阶段幼和仔虾都有很强的致病作用。其中,对蚤状幼体致病性最强,其次是无节幼体、糠虾和仔虾。     

中国对虾聚缩虫病的防治

中国对虾幼体的聚缩虫病是对虾育苗中常见的、危害较大的虾病，它感染速度快，几天之内便可使培育池中的对虾幼体８０％以上感染，如不及时防治，可导致育苗失败。 一、病原体 对虾幼体聚缩虫病的病原体常见种是树状聚缩虫，属原生动物门、纤毛虫纲、缘毛目、钟虫科。聚缩虫寄附于中国对虾蚤状幼体、糠虾幼体、仔虾及成虾的体表和鳃。 二、发病过程及症状 对虾蚤状幼体、糠虾幼体及仔虾都容易感染聚缩虫，尤以蚤状幼体、糠虾幼体的聚缩虫病危害最大。１９９９年，大连市金州区北海村育苗室对虾蚤状幼体第Ⅲ期时，５月１４日发现第２０号培育…     

1993～1994年山东省中国对虾育苗期病毒感染的流行病学调查

１９９３年和１９９４年育苗期，在山东省十余家育苗场采集了亲虾、受精卵、无节幼体、蚤状幼体、糠虾幼体和仔虾等样品共５６份。组织病理学切片观察说明，所有样品均未检查出对虾暴发性流行病病原ＨＨＮＢＶ的病理变化；ＨＰＶ的病理变化主要在亲虾、糠虾幼体和仔虾中检出，蚤状幼体有ＨＰＶ感染的可疑情况。１９９４年，５．５％的糠虾幼体和５．１％的仔虾检出有ＨＰＶ的感染。在糠虾和仔虾阶段，海捕亲虾苗种的ＨＰＶ带毒率为４．０％，越冬亲虾苗种的带毒率为６．２％。ＨＰＶ和ＨＨＮＢＶ的单克隆抗体ＥＬＩＳＡ检测方法表明有３个样品为可疑的ＨＨＮＢＶ阳性；有１２．５％～２５％的糠虾期育苗池和７０％的仔虾期育苗池存在有ＨＰＶ的感染。     

中国对虾杆状病毒垂直传播途径的初步探讨

中国对虾杆状病毒垂直传播途径的研究对切断病毒的传播途径，培育健康的对虾种质资源，具有重要的理论和实践意义。本文利用电镜技术，对中国对虾亲虾的卵巢，卵细胞和无节幼体，溲状幼体，糠虾，仔虾，幼成虾进行病毒检测，结果发现卵巢和卵细胞中有似病毒粒子，无节幼体，糠虾，仔虾，幼成虾有杆状病毒感染，并初步探讨了中国对虾杆状病毒垂直传播的可能性。     

白斑综合症病毒（WSSV）对中国对虾卵及各期幼体人工感染的试验研究

用感染白斑综合症毒病的中国对虾头胸甲，对健康的仔虾进行了人工投喂感染实验，同时从病虾中分离出病毒悬液作为毒种，无节幼体，蚤体 幼体和糠虾体进行不同温度条件下的人工浸浴实验，结果表明，卵和无节幼体，蚤状幼体，糠虾幼对病毒悬液不敏感,闰理切片观察未见病毒粒子，光镜病理切片可观空到鳃上皮，前肠上皮有包涵体样病变，同时在肝胰组织中发现了肝胰腺细小病毒（HPV）包涵体。     

关于对虾人工育苗技术之二对虾育苗中固着纤毛虫病的防治

在对虾育苗生产中,固着纤毛虫病是经常发生的一种寄生虫病.对虾蚤状幼体期、糠虾幼体期及仔虾期都容易患上固着纤毛虫病,尤其是蚤状幼体期和糠虾幼体期易感染此病,危害性最大,它直接影响对虾幼体成活率,是对虾育苗能否成功的关键一环.     

基于InDel标记的斑节对虾早期性别鉴定方法的建立

为分辨斑节对虾(Penaeus monodon)发育早期的性别,利用改良的插入/缺失(InDel)标记追踪了从受精卵、无节幼体、溞状幼体、糠虾幼体、仔虾后1 d (PL1)、仔虾后30 d (PL30)及亚成虾个体的性别,建立了测序和荧光定量PCR熔解曲线的检测方法。结果表明,InDel标记可扩增获得雌雄特异性序列,用测序法判定亚成虾性别的结果与外部观察结果一致,准确率达100%,对受精卵、无节幼体、溞状幼体及糠虾幼体均可得到雌雄特异性序列;进而建立了基于SYBR Green实时荧光定量PCR (Quantitative real-time polymerase chain reaction,q RT-PCR)熔解曲线的快速鉴定斑节对虾性别的方法,其中雄性特异序列的熔解温度(Melting temperature, Tm)为(79.10±0.10)℃,雌性为(78.45±0.20)℃,通过特异的熔解曲线可准确区分PL30、亚成虾和无节幼体Ⅵ期个体,准确率可达96.3%以上。     

Lethal Effect of Nitrite on Metapenaeus ensis Larvae

Metupenaeus ensis larvae at different stages were exposed to a series of nitrite-N (nitrite as nitrogen) concentrations in static renewal toxicity tests. Larvae at zoea stage were the most susceptible, and postlarvae were the most tolerant to nitrite among the larvae tested. The 24 h LC₅₀s were 31.29, 16.05, 47.60 and 70.06 mg/L nitrite-N for third nauplius substage (N3). second zoea substage (Z2), second mysis stage (M2), and first postlarva substage (PL1), respectively, in 33 ppt seawater at a pH of 8.20 and a water temperature of 30 C. The 48 h LC₅₀ for M2 and PL1 were 20.67 and 27.10 mg/L nitrite-N, respectively. The "threshold time" was 108 h, and the "incipient LC₅₀" for M. ensis PL1 was 7.06 mg/L nitrite-N. A "safe level" for rearing M. ensis larvae was estimated to be 0.71 mg/L nitrite-N in the hatchery.     

复方三氯异氰尿酸对短沟对虾各期幼体的毒性

用静水试验法研究了复方三氯异氰尿酸（TCCA，强氯净）对短沟对虾（Penaeus semisuicatus）各期幼体的急性毒性。无节幼体和涵状幼体试验设6个质量浓度组（0．5mg·L-1、1．0mg·L-1、1．5mg·L-1、2．0mg·L-1、2．5mg·L-1、3．0mg·L-1）和1个空自组，糠虾幼体和仔虾设7个质量浓度组（1．0mg·L-1、1．5mg·L-1、2．0mg·L-1、2．5mg·L-1、3．0mg·L-1、3．5mg·L-1、4．0mg·L-1）和1个空白组，每组3个平行。结果显示，24h半致死质量浓度（LC50）和48h LC50的95％置信区间分别是无节幼体1．47～1．78mg·L-1和1．34～1．46mg·L-1；泾状幼体1．67～1．78mg·L-1和1．23～1．36mg·L-1；糠虾幼体2．05～2．25mg·L-1和1．58～1．79mg·L-1；仔虾3．14～3．38mg·L-1和2．59～2．78mg·L-1。安全质量浓度（SC）分别是无节幼体0．30mg·L-1，溢状幼体0．22mg·L-1，糠虾幼体0．34mg·L-1，仔虾0．55mg·L-1。试验结果可为短沟对虾育苗安全用药提供参考。     

关于新对虾属Metapenaeus幼体发育分期的探讨

新对虾属Ｍｅｔａｐｅｎａｅｕｓ为对虾科Ｐｅｎａｉｄａｅ中的重要类群，随着养虾业的发展，新对虾越来越受到重视。在人工育苗中，虾类幼体发育分期对指导生产有现实意义。国外学者Ｍ．Ｓ．Ｍｕｔｈｕ等（１９７８）对近缘新对虾和道氏新对虾的糠虾（Ｍｙｓｉｓ）阶段分为５期，并在第Ⅴ期糠虾幼体之后增加两个中间期，形成Ｎ－Ｚ－Ｍ－Ｉ的“６－３－５－２”模式。作者在中型新对虾的幼体变态实验观察中注意到，糠虾幼体在一次蜕皮后其体长和附肢形态均有渐微的变化，这种形态上的细微差异不宜作为分期的依据，幼体分期的主要依据以蜕皮为标志。因此新对虾属的幼体发育分期可借鉴中国对虾（Ｐｎｕａｅｕｓｏｒｉｅｎｔａｌｉｓ）幼体分期模式划分，即Ｎ－Ｚ－Ｍ为“６－３－３”。     

Bacterial flora in the digestive tract of prawns, Penaeus japonicus Bate

Bacterial flora in the gut of wild cultured prawns, Penaeus japonicus Bate, were investigated and the isolated strains were classified to genera. The flora in the water and mud environment which the prawn inhabits were also investigated. In the water of the prawn culture tank, the highest bacterial number was counted in the zoea stages (1.8 × 10⁵ /ml) and the numbers decreased from the end of the mysis stage to the postlarval stage.Few differences in composition were observed between the two populations. In the digestive tract of the zoea, Vibrio spp. were the dominant genera. In the adult stage, Pseudomonas spp. were the most abundant in the flora of the digestive tract of prawns cultured for 126 days. One prawn that grew poorly had large numbers of the Aeromonas and Vibrio groups in the digestive tract. In the digestive tract of wild prawns, the Pseudomonas group was the dominant bacterial population.     

Developmental stages of kuruma shrimp, Penaeus japonicus Bate, susceptible to baculoviral mid-gut gland necrosis (BMN) virus

Abstract. The stages of kuruma shrimp susceptible to BMNV were determined by water-borne infection at the fertilized egg, nauplius, zoea, mysis, and 2-day (P-2), 4-day (P-4), 6-day (P-6), 8-day (P-8) and 10-day-old (P-10) post-larval stages. Susceptibility to infection tended to decrease with advancing stages of development from zoea to P-10. The stages from zoea to P-4 were very susceptible, with much higher mortality and lower growth rates in virus inoculated animals compared to controls. P-6 shrimp were also highly susceptible with all inoculated animals becoming infected with the virus. However, this group grew only slightly less well than controls and no mortality was observed. P-8 and P-10 post-larvae were refractory to the disease showing no mortality and no loss of growth, even though some were slightly infected with the virus. Fertilized eggs and nauplii did not become infected with the virus using water-borne inoculation.     

Cu~(2+)对南美蓝对虾无节幼体的急性致毒研究

研究了Cu2+对南美蓝对虾(Penaeus stylirostris)无节幼体的急性毒性影响。当Cu2+浓度不同时,无节幼体的活性和死亡率均有较大变化,其中12h和24h的半致死浓度(LC50)分别为0.132mg/L和0.102mg/L。实验结果及与其他种类毒性实验的比较表明,Cu2+对南美蓝对虾无节幼体毒性作用明显,并产生畸形现象及对变态率的影响。从而得到Cu2+对南美蓝对虾无节幼体的24h LC50和安全浓度,所得值高于国家海水水质标准值。     

刀额新对虾工厂化育苗技术

培育刀额新对虾无节幼体时以单细胞藻类作开口饵料，有利于提高成活率；糠虾期、仔虾期在低盐度（Ｓ１８．６６）中生长速度快于在高盐度中，且在逐级递降的淡化过程中，仔虾的成活率较高，这期间投喂轮虫，适合于糠虾、仔虾捕食，轮虫蚕食水中的有机碎屑，有利于水质的改善。     

非离子氨氮对罗氏沼虾幼体的毒性研究

通过非离子氨氮对罗氏沼虾幼体的急性致毒试验表明：Ⅴ期幼体９６ｈ的半致死浓度（ＬＣ５０）值为１．１４ｍｇ／Ｌ，安全浓度（ＳＣ）值为０．１１ｍｇ／Ｌ；Ⅸ期幼体９６ｈ的ＬＣ５０值为１．４０ｍｇ／Ｌ，ＳＣ值为０．１４ｍｇ／Ｌ，建议在育苗期间加强水质管理，有效地控制水体中非离子氨氮的浓度。     

Evaluation of frozen Umbrella‐stage Artemia as first animal live food for Litopenaeus vannamei (Boone) larvae

An alternative larval shrimp feeding regime, in which umbrella‐stage Artemia were constituting the first zooplankton source was evaluated in the culture of Litopenaeus vannamei. In a preliminary experiment, umbrella‐stage Artemia were fed to larvae from zoea 2 (Z2) to mysis 2 (M2) stages to identify the larval stage at which raptorial feeding starts and to determine daily feeding rates. The following experiment evaluated the performance of two feeding regimen that differed during the late zoea/early mysis stages: a control treatment with frozen Artemia nauplii (FAN), and a treatment with frozen umbrella‐stage Artemia (FUA). The ingestion rate of umbrella‐stage Artemia increased from nine umbrella per larvae day^?1 at Z2 stage to 21 umbrella per larvae day^?1 at M2. A steep increase in ingestion and dry weight from Z3 to M2 suggests a shift to a raptorial feeding mode at the M1 stage. Treatment FUA exhibited a significantly higher larval stage index (P < 0.05) during the period that zoea larvae metamorphosed to the mysis stage, and a higher final biomass, compared with treatment FAN. Based on these results and on practical considerations, a feeding regime starting with umbrella‐stage Artemia from Z2 sub‐stage can be recommended for L. vannamei larvae rearing.