Dopamine modulates the physiological response of the tiger shrimp Penaeus monodon

Levels of glucose, lactate, pO₂, pCO₂, HCO₃⁻, TCO₂, Na⁺, K⁺, Cl⁻, protein, and oxyhemocyanin in the hemolymph and its osmolality and pH were measured when tiger shrimp, Penaeus monodon (13.5 ± 1.5 g body weight), were individually injected with saline or dopamine at 10^− 8, 10^− 7, or 10^− 6 mol shrimp^− 1. Results showed that hemolymph glucose, lactate, pCO₂, HCO₃⁻, and TCO₂ values increased from 2 to 4 h; hemolymph osmolality, Na⁺, and total protein had increased at 2 h; and hemolymph K⁺ decreased from 2 to 8 h after the dopamine injection. All physiological parameters returned to the control values 4–16 h after receiving dopamine. The dopamine injection also significantly decreased the oxyhemocyanin/protein ratio of P. monodon which occurred at 2 h, resulting from an elevation of hemolymph protein and a slight decrease of oxyhemocyanin. These results suggest that stress-inducing dopamine caused a transient period of modulation of energy metabolism, osmoregulation, respiration, and the acid–base balance in P. monodon in adapting to this environmental stress.     

浙北地区利用冬闲虾塘饲养日本对虾的试验

利用饲养南美白对虾的冬闲虾塘 ,采取精养模式养一茬日本对虾 ,可提高围塘养殖的综合效益。本试验的放养密度为 2× 10 4余尾 / 6 6 7m2 ,单产 38.5kg/ 6 6 7m2 ,成活率 2 3.3%。盐度控制在 17以上     

Dietary potassium requirement of juvenile grass shrimp Penaeus monodon

ABSTRACT: A feeding trial was conducted to estimate the minimal dietary potassium (K) requirement for juvenile grass shrimp Penaeus monodon . Purified diets with seven levels (0, 0.3, 0.6, 0.9, 1.2, 1.5, 2.0 g/100 g) of supplemental potassium were fed to P. monodon (mean initial weight 0.75 ± 0.01 g) for 8 weeks. Each diet was fed to three replicate groups of shrimp. The rearing water contained 360 mg/L potassium. Weight gain and protein efficiency ratio (PER) of shrimp improved as dietary potassium supplementation level increased up to 1.5 g K/100 g diet and thereafter declined significantly ( P < 0.05). Feed efficiency (FE) of shrimp also showed a similar trend. However, whole body K concentration of the shrimp kept an increasing trend up to 2.0 g K/100 g diet. Analysis of the weight gain (percent) and PER of the shrimp by polynomial regression indicate that the minimal dietary potassium requirement in growing P. monodon is approximately 1.2 g/100 g.     

斑节对虾GRP94基因的克隆及其在不同应激条件下的表达与分析

以斑节对虾(Penaeus monodon)为研究对象,利用RACE技术克隆得到了斑节对虾Pm GRP94基因c DNA全长,并对其结构进行生物信息学分析。Pm GRP94全长2 990 bp,包括75 bp的5'UTR、527 bp的3'UTR和2 388bp的ORF。利用实时定量PCR技术,对Pm GRP94组织特异性及其在不同p H、盐度和3种重金属应激下转录水平变化情况及特点进行了研究。结果显示,Pm GRP94基因存在组织特异性,并在肝胰腺中的表达量最高;不同的应激条件下其表达具有明显差异,其中在p H、铜(Cu)和锌(Zn)的应激下Pm GRP94的表达显著升高。因此预测该基因可以作为斑节对虾受p H、Cu和Zn胁迫的指示基因。     

斑节对虾Toll9受体基因免疫功能的研究与表达分析

Toll受体蛋白(Toll receptors)是一类重要的模式识别受体,在无脊椎动物先天性免疫系统中发挥重要作用。文章对斑节对虾(Penaeus monodon)新型Toll9受体基因(Pm Toll9)进行了研究:以人源胚胎肾细胞(HEK293T)成功构建体外细胞免疫模型,通过免疫印迹方法证实Pm Toll9重组真核蛋白可在HEK293T中成功表达。双荧光素酶报告系统检测发现在200 ng转染浓度处Pm Toll9对NF-κB报告基因的激活效果显著。q RT-PCR数据证明PmToll9成功激活HEK293T细胞Toll-like receptor(TLR)信号通路,促进通路下游髓样分化因子(My D88)、肿瘤坏死因子(TNF-α)和白介素(IL-10)的上调表达,同时酶联免疫吸附测定结果证明Pm Toll9可促进TNF-α蛋白表达水平显著上调。斑节对虾体内细菌刺激实验结果显示无乳链球菌(Streptococcus agalactiae)可激活Pm Toll9在肝胰腺、肠、淋巴和鳃中的表达,哈维氏弧菌(Vibrio harveyi)可显著抑制Pm Toll9在肝胰腺中的表达。提示无乳链球菌可通过Pm Toll9激活Toll信号通路,引起机体免疫防御反应,而哈维氏弧菌对此过程具有一定的抑制作用。     

中国对虾体外人工授精方法研究

研究了中国对虾的人工授精，实验表明：解剖亲虾后取卵的时间不应超过５ｍｉｎ，精子在海水中的时间不应超过１５ｍｉｎ，卵子接触海水的时间不应超过１ｍｉｎ，本文介绍了中国对虾外人工授精技术，并对影响人工授精成功的因素以及体外人工授精的意义进行了讨论。     

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。     

南美白对虾双茬淡化养殖技术研究

研究采用南美白对虾塑料大棚保温三级淡化暂养技术等措施,实现南美白对虾池塘双茬淡化养殖。养成期间水质情况良好,水温平均（26±3）℃,pH值约8．5左右,溶氧量5．6m叽以上,氧氮约0．20mg/L,亚硝酸氮0．02m班左右,每667m^2养殖产量达426．7kg,养殖效益高达4186．7元。结果表明,采用南美白对虾双茬淡化养殖技术,延长了对虾生长期,提高了池塘利用率和经济效益,具有较好的推广价值.     

Pharmacokinetics of oxolinic acid and oxytetracycline in kuruma shrimp, Penaeus japonicus

The pharmacokinetics of oxolinic acid and oxytetracycline were examined in kuruma shrimp (Penaeus japonicus) after intra-sinus (10 and 25 mg/kg, respectively) and oral (50 mg/kg) administration. The shrimp were kept in tanks with recirculated artificial seawater at a salinity of 22–23 ppt. The water temperature was maintained at 25±0.6 °C. The hemolymph concentrations of both drugs after intra-sinus dosing were best described by a two-compartment open model. The distribution and elimination half-lives (t_1/2 and t_1/2β) were found to be 0.59 and 33.2 h for oxolinic acid and 0.45 and 24.7 h for oxytetracycline, respectively. The apparent volume of distribution at a steady state (V_ss) and total body clearance (CL_b) were estimated to be 1309 ml/kg and 28.8 ml/kg/h for oxolinic acid and 748 ml/kg and 22.7 ml/kg/h, respectively. The hemolymph concentration–time curves after oral administration did not fit by the nonlinear least squares method using one- and two-compartment model with first-order absorption in either of the drugs. The peak hemolymph concentration (C_max), the time to peak hemolymph concentration (t_max) and the elimination half-life were found to be 17.8 μg/ml, 7 h and 34.3 h for oxolinic acid and 24.3 μg/ml, 10 h and 33.6 h for oxytetracycline, respectively. The bioavailability (F) after oral administration was 32.9% for oxolinic acid and 43.2% for oxytetracycline. The hemolymph protein binding in vivo was determined to be 36.7±8.5% for oxolinic acid and 22.9±4.8% for oxytetracycline.     

头孢氨苄对斑节对虾幼体发育及育苗水体细菌数量的影响

研究了不同浓度头孢氨苄(Cefalexin)对斑节对虾Penaeusmonodon幼体发育以及对斑节对虾育苗水体中异养菌总数和弧菌数量的影响。在试验初期,无论是对照组还是施用头孢氨苄的各试验组,育苗水体中的总异养菌数量和弧菌数量都呈现出较为明显的上升趋势;在第二次施用头孢氨苄后,各试验组的异养菌总数和弧菌数量的增幅明显低于对照组(或出现异养菌总数和弧菌数量缓慢下降),而对照组异养菌总数和弧菌数量则呈现显著的上升。施用0.5～1.0μL·L-1头孢氨苄对育苗水体中的总异养菌有显著的杀灭及抑制作用,但对弧菌数量杀灭及抑制作用并不显著;施用1.5μL·L-1头孢氨苄对育苗水体中的总异养菌和弧菌数量的杀灭及抑制作用显著。当幼体变态发育至仔虾第8天(P8)时,对照组异养菌总数和弧菌数量分别达6.33×105和3.55×104CFU·mL-1,均远远高于试验组的异养菌总数和弧菌数量增长的幅度。试验组的幼体变态到P1期的时间,比对照组缩短了10h以上;试验组的成苗率也比对照组提高了3.2%～13.1%。