氨氮和亚硝酸氮对南美白对虾的毒性研究

用通常的生物毒性试验方法进行了氨氮和亚硝氨氮对体长5cm南美白对虾的急性毒性试验。在海水pH8.15、水温T＝27℃、盐度S＝20．0‰条件下，求得了两种物质对南美白对虾24h、48h、72h、96h的半死浓度，提出总氨氮和非离子氨氮对南美白对虾的安全浓度分别为2．667mg/L和0．201mg/L，亚硝酸氮的安全浓度为5．551mg/L。氨氮对南美白对虾的毒性强于亚硝酸氮，并提出降低氨氮和亚硝酸氮含量的措施。     

新型高效络合碘对鲤(Cyprinus carpio Linnaeus)、南美白对虾(Litopenaeus vannamei Boon)的急性毒性和抑菌效果试验

采用常温静水试验,探讨了高效络合碘对鲤鱼、南美白对虾的急性毒性效应;同时进行了高效络合碘对嗜水气单胞菌(Aeromonas hydrophila)的抑菌试验.结果表明:高效络合碘对鲤鱼、南美白对虾的24 h、48 h、96 h半致死浓度(LC<,50>)分别为52.99 mg/L、47.07 mg/L、38.87 mg/L和88.20 mg/L、62.48 mg/L、47.04 mg/L,安全浓度分别为3.89 mg/L和4.70 mg/L.22℃,1%高效络合碘对嗜水气单胞菌的最低杀菌体积分数为2.5×10<'4>,杀菌率达100%.实验表明,新研制的高效络合碘与其它碘制剂相比具有高效、低毒、杀菌抑菌的效果,值得大规模的推广.     

北方地区南美白对虾、河蟹早繁苗中间培育技术

应用臭氧技术、微生态制剂、营养和环境等集成技术进行南美白对虾、河蟹早繁苗的中间培育,水温25～30℃,盐度1.8～2.2,pH值7.7～8.3,氨氮0.8～1.2 mg/L,溶氧6 mg/L.扣蟹成活率76.5%,南美白对虾苗种成活率84.0%.     

4种常用药物对克氏双锯鱼稚鱼急性毒性试验

选用硫酸铜、敌百虫、福尔马林、上野黄药对克氏双锯鱼稚鱼进行急性毒性试验.硫酸铜对克氏双锯鱼稚鱼24 h LC50为0.80 mg/L,48 h LC50为0.70 mg/L,96 h LC50为0.60 mg/L,安全质量浓度为0.16 mg/L;敌百虫对克氏双锯鱼稚鱼24 h LC50为2.88 mg/L,48 h LC50为2.44 mg/L,96 h LC50为2.12 mg/L,安全质量浓度为0.53 mg/L.福尔马林和上野黄药对克氏双锯鱼稚鱼的96 h LC50＞100 mg/L,属于低毒.根据96 h半致死质量浓度来判断药物的毒性大小,克氏双锯鱼稚鱼对4种药物敏感性依次为:硫酸铜>敌百虫>福尔马林和上野黄药,福尔马林和上野黄药对克氏双锯鱼稚鱼同属于低毒药品.     

孢虫清对8种常见淡水养殖动物急性毒性试验

采用静态生物毒性试验方法研究孢虫清(环烷酸铜溶液25%)对常见的8种淡水养殖动物草鱼、彭泽鲫、鲢、彩鲫、锦鲤、黄颡鱼、青虾、河蟹的急性毒性,结果表明该药物对草鱼、彭泽鲫、鲢、彩鲫、锦鲤、黄颡鱼的96h LC50分别为2.905、3.450、2.243、3.638、3.638、4.084 mg/L,安全浓度分别为0.2905、0.3450、0.2243、0.3638、0.3638、0.4084 mg/L。对青虾的安全浓度<0.2mg/L,对河蟹安全浓度范围为9.12～20mg/L。     

“毒死蜱”对南美白对虾的急性毒性影响

采用静水生物测试法研究"毒死蜱"对南美白对虾的急性毒性.结果表明:"毒死蜱"对南美白对虾24、48、72、96 h的LC50分别为3.44、2.08、1.36、0.89μg/L,其安全浓度为O.0089μg/L.南美白对虾对"毒死蜱"敏感,带有极微量"毒死蜱"的稻田水流人养殖水体,也会对南美白对虾产生严重危害.田间施药,要注意对周围养殖生物的安全距离和浓度.     

“混养车轮净”对10种常见淡水养殖动物的毒性试验

采用静态生物毒性试验方法研究“混养车轮净”(阿维菌素5％)对常见的10种淡水养殖动物草鱼、鳊、彭泽鲫、鳙、鲢、彩鲫、锦鲤、黄颡鱼、河蟹、青虾的急性毒性,结果表明该药物对草鱼、鳊、彭泽鲫、鳙、鲢、彩鲫、锦鲤的96h LC50分别为2.2736、1.9477、1.9055、1.5201、1.4676、1.9911、2.0693 mg/L,安全浓度分别为0.2274、0.1948、0.1906、0.1520、0.1468、0.1991、0.2063 mg/L.对黄颡鱼的安全浓度范围为0.5～1 mg/L,对青虾和河蟹的安全浓度范围为10～ 20 mg/L.     

PVP-碘对南美白对虾无节幼体的急性毒性试验

采用静水试验法，用PVP-碘对南美白对虾无节幼体进行了急性毒性试验。试验结果表明：PVP-碘对南美白对虾无节幼体的24h及40h半致死浓度分别为8.737mg/L及6.512mg/L，其安全浓度为0.65mg/L。     

南美白对虾耗氧率和窒息点的初步测定

对2种规格南美白对虾的耗氧率和窒息点进行了测定，结果表明，南美白对虾的耗氧率随体重的增加而减小，耗氧量和窒息点随体重的增加而增加，平均体长53．33mm，体重１.48g的南美白对虾耗氧率是０．４４９３mg/g.h，窒息点０.6663mg/L,平均体长７0.88mm,体重３.49g时，耗氧率为0.3004mg/g.h,窒息点1.0186mg/L，南美白对虾的耗氧率呈现明显的昼液变化规律。     

“鱼虾宝“对南美白对虾抗病力的增强效果

在南美白对虾(Penaeus vannamei)的饲料中分别添加0 mg/kg.B.W.,20.0 mg/kg.B.W.、40.0mg/kg.B.W.、60.0 mg/kg.B.W.、80.0 mg/kg.B.W.和100.0 mg/kg.B.W.的"鱼虾宝",连续投喂南美白对虾21d后,通过测定供试南美白对虾的体重和利用投喂或注射患病南美白对虾组织(浆)的攻毒方法,探讨了口服"鱼虾宝"对南美白对虾生长速度和抗病力的影响.结果表明,在南美白对虾的饲料中添加40.0 mg/kg.B.W.至100.0 mg/kg.B.W.的"鱼虾宝",对南美白对虾的生长速度和身体颜色等没有明显影响;能有效地增强供试南美白对虾的抗病力,与对照组相比,经口服攻毒后投喂不同剂量"鱼虾宝"试验组的南美白对虾有效率为63.6%～67.2%,而经注射攻毒后各试验组南美白对虾的有效率为28.6%～33.5%,口服攻毒后的有效率稍高可能与病原体的感染方式有关.     

底泥悬浮物对海水养殖凡纳滨对虾仔虾生物毒性影响

为评价疏浚、吹填过程中产生的底泥悬浮物对南海区凡纳滨对虾仔虾的毒性影响,根据《水质-物质对淡水鱼(斑马鱼)急性致死毒性的测定》方法,对南海区凡纳滨对虾仔虾的生物毒性影响进行了分析。结果表明:疏浚区海水中底泥悬浮物浓度超过10mg/L,持续12h,对凡纳滨对虾仔虾产生一定的致死效应。底泥悬浮物浓度超高80mg/L,且持续48h以上,将对仔虾产生严重的影响,甚至导致全部仔虾的死亡。根据仔虾的死亡概率和底泥悬浮物浓度对数,分别计算出12h、24h、36h、48h的半致死量(LC50)为54.56、40.29、25.89、19.18mg/L。     

Acute and Chronic Effects of Nitrite on White Shrimp, Litopenaeus vannamei, Cultured in Low-Salinity Brackish Water

The marine white shrimp Litopenaeus vannamei is widely cultured. Recently, farmers have begun to culture this shrimp in low-salinity brackish water (< 6 g/L). The intensification of shrimp culture often results in occurrences of elevated nitrite concentration during the growing season. Nitrite is toxic to shrimp and exposure to high concentrations may cause retarded growth and mortalities. The current study was aimed at investigating the acute and chronic toxicity of nitrite to L. vannamei grown in low-salinity (2 g/L) brackish water. Studies of the 96-h EC50 and LC50 values of nitrite were performed to determine the acute toxicity, and an aquarium growth study (2 d post exposure to elevated nitrite concentrations) was conducted to evaluate the chronic effects of nitrite on shrimp production. The 96-h EC50 and LC50 values for juvenile L. vannamei grown in water of 2 g/L salinity was about 9 mg/L NO₂-N, suggesting a safe concentration for shrimp production in ponds to be less than 0.45 mgIL NO₂-N. Exposing shrimp to nitrite concentration of 4 mg/L for 2 d reduced their growth but did not affect their survival.     

氯苯对四种海洋生物的急性毒性研究

采用半静水法研究了氯苯对三疣梭子蟹、黄姑鱼、脊尾白虾和菲律宾蛤仔4种海洋生物的急性毒性作用.试验结果表明,在海水pH 7.9～8.2、水温24.1～24.5 ℃、盐度27.8～29.2条件下,氯苯对三疣梭子蟹、黄姑鱼、脊尾白虾和菲律宾蛤仔的96 h LC50分别为52、15、0.39、91 mg/L.综合氯苯对4种海洋生物的毒性机理和急性毒性数据,氯苯对海洋生物的毒性依次为:脊尾白虾>黄姑鱼>三疣梭子蟹>菲律宾蛤仔.氯苯对三疣梭子蟹、黄姑鱼、脊尾白虾和菲律宾蛤仔的安全质量浓度分别为0.52、0.15、0.0039、0.91 mg/L.     

Eradication of predatory fishes in shrimp farms by utilization of Thai tea seed

The chief predatory fishes found in shrimp culture ponds in Thailand are Tilapia mossambica, Lates calcarifer, Scatophagus argus, Eluetheronema tetradactylum, Goviupterus chuno, Mystus sp., and other gobies. The eradication of predators, mostly fishes, is necessary for good management of any shrimp farm. Tea seed grown in northern Thailand has been used for this purpose. Quantitative analysis of crude saponin in the tea seed was conducted and some biological tests on the toxicity of crude saponin to fish were performed.The effective dosage of crude saponin for the eradication of predatory fishes was 1.1 ppm, but shrimp, crabs, copepoda, rotifers and brine shrimp (Crustacea) all survived this concentration. The lethal time for fishes increased in proportion to their body weight and the salinity of the pond. The toxicity of the saponin weakened with time.     

盐度胁迫下维生素E对南美白对虾体内抗氧化物质含量的影响

盐度是影响虾类生存生长的重要生态因子，维生素E是机体重要的抗氧化物质。本文通过毛细管电泳法研究了不同盐度条件下添加维生素E对南美白对虾内维生素C及NAD含量的影响，结果表明：南美白对虾饵料中维生素E的添加量为100mg／kg时，能使虾肝胰腺内的Ve和NAD的含量显著增大，发挥正常的抗氧化作用，增强南美白对虾对盐度突变的耐受力。     

Experimental host range and histopathology of white spot syndrome virus (WSSV) infection in shrimp, prawns, crabs and lobsters from India

Experimental studies were conducted by injecting or feeding white spot syndrome virus (WSSV) derived from infected shrimp, Penaeus monodon (Fabricius), collected from the south-east coast of India, to five species of shrimp, two species of freshwater prawns, four species of crabs and three species of lobsters. All species examined were susceptible to the virus. Experimental infections in the shrimp had the same clinical symptoms and histopathological characteristics as in naturally infected P. monodon . A cumulative mortality of 100% was observed within 5–7 days in shrimp injected with WSSV and 7–9 days in shrimp fed with infected tissue. Two species of mud crab, Scylla sp., survived the infection for 30 days without any clinical symptoms. All three species of lobsters, Panulirus sp., and the freshwater prawn, Macrobrachium rosenbergii (De Man), survived the infection for 70 days without clinical symptoms. However, bioassay and histology using healthy P. monodon revealed that crabs, prawns and lobsters may act as asymptomatic carriers/reservoir hosts of WSSV. This is the first report to suggest the carrier/reservoir capacity of these hosts through histological and bioassay evidences. Ultrastructural details of the virus in experimentally infected shrimp, P. vannamei , (Boone), were also studied.     

溴氰菊酯对日本对虾的急性毒性及积累试验研究

采用半静态换水补药的方法,开展溴氰菊酯对日本对虾的急性毒性及积累试验,并且记录下不同溴氰菊酯浓度下日本对虾的中毒症状。通过试验获得溴氰菊酯对日本对虾24h、48h、72h和96h的半致死浓度(LC50)值分别为0.00090mg/L、0.00050mg/L、0.00019mg/L、0.00012mg/L,96h安全质量浓度为0.046μg/L。通过药物积累试验表明在试验期间内,水体中溴氰菊酯浓度与受试生物体内溴氰菊酯的积累量成负相关。     

氨、亚硝酸盐和硝酸盐对凡纳滨对虾幼虾的毒性作用

研究了 NH₃-N、NO₂ ^- -N与 NO₃ ^- -N对凡纳滨对虾幼虾的毒性作用。获得了 NH₃-N_t(NH₃-N_m) 与 NO₂ ^- -N对体长2．4cm幼虾的 24h、48h、72h、96h之 LC₅₀值，两者对幼虾的安全质量分数分别为1．30 (0．101)mg/L和3．80mg/L。当 NH₃-N_t(NH₃-N_m)质量分数在1．3(0．101)~4．3(0．333)mg/L时，存活率为71．4% ~92．9%，体长增长率为36．3% ~57．1%，体重增长率为188．5% ~322．3%。当 NO₂ ^- -N质量分数在3．00~21．00mg/L时，成活率为75．0% ~91．7%，体长增长率为21．2% ~59．2%，体重增长率为72．0% ~311．9%。NO₃ ^- -N对体长7．37cm幼虾的亚急性毒性效应：NO₃ ^- -N的质量分数在 30~195mg/L时，成活率为 35% ~100%，体长增长率为8．5% ~20．5%，体重增长率为29．6% ~56．8% 。三态氮在一定质量分数范围内均对幼虾的存活率和生长率产生影响。     

凡纳滨对虾营养生理和高效环保饲料研究进展

凡纳滨对虾(Penaeus vannamei)是我国最主要的海水对虾类养殖品种,2021年海水养殖产量达到119.77万吨,占全国海水虾类养殖总产量的80%以上。目前,国内外对于凡纳滨对虾的营养需求与饲料研究已有较多报道,但是对于不同生长阶段的精准营养需求以及营养素和功能性饲料添加剂的相互关系研究仍不够深入。本文主要就其蛋白质、脂肪、碳水化合物和微量营养素的需求,蛋白源和脂肪源替代鱼粉和鱼油,功能性饲料添加剂应用等方面的研究进展进行综述,以期为凡纳滨对虾的精准营养研究及高效环保饲料的开发提供科学参考,从而推动其养殖业的健康可持续发展。