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。     

应用人工半咸水进行罗氏沼虾繁殖试验初报

本文探讨了罗氏沼虾亲虾培育，人工半咸水育苗技术，结果表明：水温２８．５±０．５℃时，罗氏沼虾相邻两次产卵间隔时间为３０－４０天，从产卵到第一期蚤状幼体孵出需１４—１６天，水温２９．５±０．５℃时，从第一期蚤状幼体卵出到虾苗淡化需２６天。水簇箱中进行罗氏沼虾育苗试验，取得了淡化虾苗产量为８１尾／升和９４尾／升的结果。     

罗氏沼虾幼体及成虾消化酶活性

罗氏沼虾幼体及成虾消化酶活性魏华，赵维信（上海水产大学，上海２０００９０）关键词罗氏沼虾，幼体，消化酶ＴＨＥＡＣＴＩＶＩＴＩＥＳＯＦＤＩＧＥＳＴＩＶＥＥＮＺＹＭＥＳＯＦＬＡＲＶＡＥＡＮＤＡＤＵＬＴＩＮＭＡＣＲＯＢＲＡＣＨＩＵＭＲＯＳＥＮＢＥＲＧＩＩ￥...     

白莲湖水化学研究

本文对白莲湖精养期间的水化学进行了研究１）该湖属Ｓｉ＾Ｎａ含盐量，总碱度和总硬度均偏低。２）有效氮含量平均０．７２８毫克／升，其中ＮＨ４－Ｎ，占９７．５％，ＰＯ＾３－Ｐ平均０．０１５毫克／升，Ｎ／Ｐ平均４８．５，磷是限制性营养元素，硅酸盐（ＳｉＯ２）适中，３）ＰＨ，ＤＯ适宜，ＣＯＤ平均１２．１５毫克／升，ＤＯ和ＣＯＤ各对应的底表层均呈正相关。     

罗氏沼虾工厂化育苗试验

利用对虾育苗场的设计进行罗氏沼虾工厂化育苗试验，于１３６ｍ＾３水体中投放状幼体１４３８万尾，育出商品仔虾９６４万尾，幼体培育成活率为６７％，平均每尾亲虾出苗４７２５尾，单位水体平均出苗量为７．０９万尾，最高为１０．２万尾／ｍ＾３。从４月上旬到５月下旬，罗氏沼虾雌性亲虾可抑卵三次以上，前后抱卵批次所孵出的幼体质量没有明显差异。试验还证明，幼体培育池内氨氮浓度高达１０５６．４μｇ／ｌ对成活率没有多大曩     

开口微囊饵料在罗氏沼虾育苗中的应用

利用杭州高成添加剂生产的“高成”牌罗氏沼虾幼体开口微囊饵料，进行罗氏沼虾育苗试验。结果：“高成”牌幼体微囊饵料替代６０％的卤虫卵，仔虾成活率达６０％以上，成本降低１／３～１／２。     

罗氏沼虾蚤状幼体耗氧速率与窒息点测定

以罗氏沼虾蚤状幼体Ｖ与ＩＸ期为试验对象，在水温２８．５±０．２℃条件下测定其瞬时耗氧速率；并将瞬时耗氧速率与时间、溶氧量作相关分析。结果：耗氧速率随时间延长、溶氧量下降而递减；蚤状幼体Ｖ与ＩＸ期昏迷点分别为２．１８ｍｇ／Ｌ，１．３４ｍｇ／Ｌ；窒息点分别为１．８５ｍｇ／Ｌ，１．２６ｍｇ／Ｌ。     

英国斯特林大学推荐养殖日本沼虾

英国斯特林大学水产养殖研究所对罗氏沼虾和日本沼虾两种幼体生长进行比较研究。通过两种沼虾幼体生长比较研究结果表明,发现日本沼虾幼体存活率高于罗氏沼虾幼体存活率20％,其日本沼虾幼体变态速度比罗氏沼虾幼体快。但日本沼虾幼体孵化数大大低于罗氏沼虾,日本沼虾幼体平均孵化数为1500尾,而罗氏沼虾幼体平均孵化数为354100尾。仔虾孵化数的严重差异,直接影响了亲虾需要量。日本沼虾     

微量元素在盐碱地新池塘配方施肥培育鱼种中的效果研究

在施足基肥的盐碱地新池塘中，将有机肥、无机肥氮、磷、微量元素按比例连续不断地配方施肥和水质调控，使水体中ＮＨ４＾＋－Ｎ＋ＮＨ３－Ｎ为０．８３５ ８ｍｇ／Ｌ，ＰＯ４＾３－－Ｐ为０．１２８ ６ｍｇ／Ｌ，ＳｉＯ２为１．４９ｍｇ／Ｌ，Ｎ／Ｐ为６．０２：１。微量元素Ｆｅ、Ｂ、Ｍｎ、Ｚｎ、Ｍｏ、Ｃｏ分别按６０、５０、５０、５、５、５μｇ／Ｌ施入池水，隐藻、硅藻为优势种群的浮游植物总生物量达到４６．９３９ｍｇ／     

盐碱地新池塘测水配方施肥培育大规格鱼种试验

根据测水数据将有机肥、无机肥氮和磷按比例少量多次施肥,使试验水体中ＮＨ４－Ｎ＋ＮＨ３－Ｎ平均值为０．８３８９ｍＬ,ＰＯ４＾３－－Ｐ为０．１２８５ｍｇ／Ｌ,Ｎ／Ｐｏ ７．３３／１,ＣＯＤ平均值为１７．８５ｍｇ／Ｌ,有机腐屑和细菌占有机悬浮物的７５％,浮游动物平均生物量为１８．５７１１ｍｇ／Ｌ,浮游植物平均生物量为４３．２１８ｍｇ／Ｌ,叶绿素为２３２．６μｇ／Ｌ,池中绿藻、隐藻、硅藻为优势种群,成功地     

Acute Toxicity of Ammonia and Nitrite to White Shrimp Penaeus setiferus Postlarvae

Penaeus setiferus postlarvae were exposed to acute levels of ammonia, nitrite, and to a mixture of both by a short-term static method, The 24h, 48-h and 72-h LC50 values for un-ionized ammonia were 1.49, 1.21 and 1.12 mg/L NH₃-N (un-ionized ammonia as nitrogen), and 11.55, 9.38 and 8.69 mg/L ammonia-N (un-ionized plus ionized ammonia as nitrogen). The 24-h, 48-h and 72-h LC50 values for nitrite were 268.06, 248.84 and 167.33 mg/L nitrite-N (nitrite as nitrogen). Nitrite was much less toxic than ammonia. The joint effect of ammonia and nitrite on the postlarvae was synergistic at 48-h exposure and antagonistic after 72 h. Postlarvae of P. setiferus may be considered as organisms sensitive to ammonia and nitrite.     

NH3-N浓度对太湖竺山湾水体及沉积物中硝化作用的影响

通过模拟培养试验,比较不同浓度非离子态氨(NH3-N)条件下,富营养化湖泊———太湖竺山湾水体及沉积物中硝化作用2个过程,即氨氧化和亚硝酸盐氧化的发生情况。结果表明,在试验设置的NH3-N浓度范围内,水体和沉积物中氨氧化速率都随着NH3-N浓度的升高显著增加(LSD检验,P<0.05),亚硝酸盐氧化速率却呈阶段性变化。水体中NH3-N浓度大于0.35 mg/L时,亚硝酸盐氧化速率开始显著降低(LSD检验,P<0.05),而氨氧化速率与亚硝酸盐氧化速率的比值从NH3-N浓度为0.15 mg/L开始随着NH3-N浓度的升高而显著增加,说明水体中亚硝酸盐氧化过程在NH3-N浓度为0.15 mg/L时已受到部分抑制;沉积物中亚硝酸盐氧化速率在NH3-N浓度大于0.65 mg/L时开始降低(LSD检验,P>0.05),而氨氧化速率与亚硝酸盐氧化速率的比值从NH3-N浓度为0.35 mg/L开始随着NH3-N浓度的升高而显著增加,说明沉积物中亚硝酸盐氧化过程在NH3-N浓度为0.35 mg/L时已受到部分抑制。太湖竺山湾水体中的NH3-N浓度为0.19 mg/L,已达到对亚硝酸盐氧化过程的抑制范围;沉积物间隙水中NH3-N浓度为0.16 mg/L,还未对亚硝酸盐氧化过程产生抑制效果。     

Effects of acute and chronic toxicity of unionized ammonia on mud crab, Scylla serrata (Forsskål, 1755) larvae

While the effects of ammonia on fish and prawn larvae are well documented, little is known of its effect on mud crab (Scylla serrata) (Forsskål, 1755) larvae. Two experiments were conducted in 5 L hemispherical plastic bowls, containing 3 L of ultra‐filtered and settled seawater and various larval stages of mud crab to (1) determine the acute median lethal concentration (LC₅₀) of unionized ammonia and (2) to determine the chronic effects of unionized ammonia on survival and percentage moulting to zoea and megalop stages. The larval stages that exhibited the highest tolerance to ammonia over 24 h were zoea 1 (LC₅₀ of 4.05 mg L^?1 of unionized ammonia) and zoea 5 (LC₅₀ of 6.64 mg L^?1 of unionized ammonia). The megalop stage had the lowest total ammonia LC₅₀ at both 24 and 48 h, making it the larval stage most susceptible to total ammonia. Exposure to 6.54 mg L^?1 of unionized ammonia resulted in 100% death of all larvae within 24 h. The tolerance of S. serrata larvae to total ammonia did not appear to increase with ontogenetic development. The results indicate that the concentrations at which total ammonia produces an acute or chronic response in mud crab larvae are far higher than those experienced in current larval production systems (0–0.5 mg L^?1 of total ammonia) used as industry standards in Australia.     

Joint Action of Ammonia and Nitrite on Tiger Prawn Penaeus monodon Postlarvae

Tiger prawn Penaeus monodon postlarvae (PL6) were exposed to a mixture of ammonia and nitrite by the static renewal method. When the toxicity ratio of the ammonia-nitrite mixture was 1:1, the 48 h, 72 h and 96 h LC50 values were 2.20, 1.43 and 0.84 toxicity units which were equivalent to 12.66 mg/L ammonia-N (0.60 mg/L NH₃-N) plus 14.91 mg/L nitrite-N, 8.23 mg/L ammonia-N (0.39 mg/L NH₃-N) plus 9.69 mg/L nitrite-N, and 4.83 mg/L ammonia-N (0.23 mg/ L NH₃-N) plus 5.69 mg/L nitrite-N. When the toxicity ratio of the ammonia-nitrite mixture was 51, the 48 h, 72 h and 96 h LC50 values were 2.50, 1.56 and 0.85 toxicity units which were equivalent to 23.98 mg/L ammonia-N (1.13 mg/L NH₃-N) plus 5.65 mg/L nitrite-N; 14.96 mg/L ammonia-N (0.71 mg/L NH₃-N) plus 3.52 mg/L nitrite-N, and 8.15 mg/L ammonia-N (0.39 mg/ L NH, N) plus 1.92 mg/L nitrite-N. A mixture of ammonia and nitrite exerted greater toxicity than high concentrations of either ammonia or nitrite alone. The combined effect of ammonia and nitrite on P. monodon postlarvae was antagonistic for 48 and 72 hours exposure, but synergistic after 96 hours exposure.     

氨氮对拟穴青蟹的急性毒性及对其血清免疫相关酶活力的影响

采用静水法研究氨氮对拟穴青蟹(Scylla paramamosain)的急性毒性及在氨氮初始浓度分别为0(C0,对照组)、10(C10组)、20(C20组)、30(C30组)、40(C40组)、50 mg/L(C50组),胁迫时间分别为0、6、24、48、72 h的条件下对其血清中碱性磷酸酶(AKP)、酸性磷酸酶(ACP)、溶菌酶(LZM)、超氧化物歧化酶(SOD)和酚氧化酶(PO)活力的影响。结果显示,总氨氮对拟穴青蟹24 h和48 h的半致死浓度分别为104.793、66.124 mg/L,安全浓度为7.90 mg/L,非离子氨对拟穴青蟹24 h和48 h的半致死浓度分别为8.396、5.298 mg/L,安全浓度为0.63 mg/L。在胁迫6、24、48与72 h时,各实验组的LZM活力均显著低于对照组(P0.01)。相较于对照组,C10、C20及C40组在24 h的AKP、ACP活力均显著升高(P0.05)。C20组在24 h的SOD活力则显著低于其他胁迫时间点(P0.05)。胁迫72 h时,C30、C40及C50组的PO活力显著高于对照组(P0.05)。该实验条件下,不高于40 mg/L的氨氮可在24 h内使拟穴青蟹血清中的AKP与ACP活力显著升高,而50 mg/L的氨氮则对其具有抑制作用;各实验组浓度氨氮均在72 h内对拟穴青蟹血清中的LZM活力具有显著的抑制作用,对PO活力具有明显的刺激作用,对SOD活力无显著影响。     

Toxicity of Ammonia and Nitrite to Penueus monodon Juveniles

Pcnaeus monodon juveniles (35.4 ± 2.2 mm TL) were exposed to seawater (20 ppt) having different concentrations of total ammonia (NH₃+ NH,+) and nitrite. Median lethal concentration (LC₅₀) was determined with static-renewal tests. The LC₅₀, of total ammonia-N, NH₃-N and niMte-N on shrimps decreased with increase of exposure time. The 24, 48, 72, % and 120 h LC₅₀ were 94.96, 61.09, 47.47 45.58 and 38.00 mg/L total ammonia-N (2.68, 1.73, 135, 1.29 and 1.08 mg/L NH₃-N) and 215.85, 185.33, 88.54, 54.76 and 37.97 mg/L nitrite-N, respectively. The 144h LC₅₀ of total ammonia-N and NH₃-N was 36.71 mg/L and 1.04 mgL. The "threshold" of ammonia and nitrite was found at 144h and 120h respectively, from the toxicity curve approaching asymptote. A "safe value" was 3.7 mg/L total ammonia-N, 0.1 mg/L NH₃-N (20 ppt, pH 7.70, 27C) and 3.8 mg/L nitrite-N for P. monodon juvenile .     

Tolerance of Snakehead Channa striatus to Ammonia at Different pH

Tolerance of snakehead Channa striatus to ammonia was tested at three pH levels (8.0, 9.0. and 10.0) in experimental tanks. At pH 8.0, ammonia LC50 estimates for snakehead at 24, 48, 72, and 96 h were >205.7, >203.5, 152.6, and 107.3 mg total ammonianitrogen (TAN)/L (or >10.3, >10.2, 7.6, and 5.4 mg NH₃-N/L), respectively. At pH 9.0, ammonia LC50 estimates at 24, 48, 72, and 96 h were >52.4, 62.8, 56.1, 43.4 mg TAN/L (or >18.0, 21.6, 19.3, and 14.9 mg NH₃-N/L), respectively. At pH 10.0, ammonia LC50 estimates at 24, 48, 72, and 96 h were 25.7, 21.6, 20.3, and 18.7 mg TAN/L (or 21.6, 18.1, 17.1, and 15.7 mg NH₃-N/L). respectively. Our data indicate that the tolerance of snakehead to ammonia was associated with pH. Thus, we recommend that snakehead should not be subjected to prolonged exposures of NH₃-N concentration more than 0.54 ma at pH 8.0, more than 1.49 mg/L at pH 9.0, or more than 1.57 mg/L at pH 10.0.     

Acute tolerance of juvenile Florida pompano, Trachinotus carolinus L., to ammonia and nitrite at various salinities

The acute tolerance of juvenile Florida pompano Trachinotus carolinus L. (mean weight±SE=8.1±0.5 g) to environmental unionized ammonia‐nitrogen (NH₃‐N) and nitrite‐nitrogen (NO₂‐N) at various salinities was determined via a series of static exposure trials. Median‐lethal concentrations (LC₅₀ values) of NH₃‐N and NO₂‐N at 24, 48, and 96 h of exposure were calculated at salinities of 6.3, 12.5 and 25.0 g L^?1 at 28 °C (pH=8.23–8.36). Tolerance of pompano to acute NH₃‐N exposure was not affected by salinity, with 24, 48 and 96 h LC₅₀ values ranging from 1.05 to 1.12, 1.00 to 1.08 and 0.95 to 1.01 mg NH₃‐N L^?1 respectively. Regarding NO₂‐N, tolerance of pompano to this environmental toxicant was compromised at reduced salinities. Median‐lethal concentrations of NO₂‐N to pompano at 24, 48 and 96 h of exposure ranged from 67.4 to 220.1, 56.9 to 140.7 and 16.7 to 34.2 mg NO₂‐N L^?1 respectively. The results of this study indicate that juvenile Florida pompano are relatively sensitive to acute NH₃‐N and NO₂‐N exposure, and in the case of the latter, especially at lower salinities.     

5种常用农药对江黄颡鱼急性毒性试验

采用静态急性毒性试验法对江黄颡鱼进行研究.5种常见农药对江黄颡鱼苗24 h LC50半致死质量浓度、48 h LC50半致死质量浓度、安全质量浓度分别为:阿维菌素0.43、0.28、0.035 mg/L;草甘磷15.38、13.43、 3.072 mg/L;啶虫咪0.13、0.09、0.013 mg/L;百草枯4.62、3.72、0.724 mg/L;复方胶悬剂550、389、58.38 mg/L.常用农药的敏感性依次为:啶虫咪>阿维菌素>百草枯>草甘磷>复方胶悬剂.     

Tolerance of juvenile black sea bass Centropristis striata to acute ammonia and nitrite exposure at various salinities

ABSTRACT:   Experiments were conducted to determine the acute tolerance of juvenile (mean weight ± standard error, 9.9 ± 0.9 g) black sea bass Centropristis striata to environmental un-ionized ammonia-nitrogen (NH₃-N) and nitrite-nitrogen (NO₂-N) exposure at various salinities. Specifically, median lethal concentrations (LC50 values) of NH₃-N and NO₂-N at 24, 48 and 96 h of exposure were determined at salinities of 10, 20 and 30 g/L at 22°C. With the exception of LC50 values determined at 48 h, median lethal concentrations of NH₃-N to black sea bass were not influenced by environmental salinity; 24, 48, and 96 h LC50 values ranged from 0.81 to 0.85, 0.65–0.77, and 0.46–0.54 mg-NH₃-N/L, respectively. In contrast, tolerance of black sea bass to environmental NO₂-N was compromised at reduced salinities. Median lethal concentrations of NO₂-N to fish at 24, 48 and 96 h of exposure ranged from 288.3 to 429.0, 258.4 to 358.8 and 190.0 to 241.9 mg-NO₂-N/L, respectively. Results indicate that while juvenile black sea bass are relatively sensitive to acute NH₃-N exposure, they are highly resistant to NO₂-N exposure.