定向交尾技术在中国对虾家系构建中的初步研究

为满足中国对虾家系选育中所需的家系材料,本研究在2004年进行了中国对虾室外和室内定向交尾实验。室外定向交尾实验采用3个不同地理群体的中国对虾,设计了5个交配组合,1尾雄虾搭配4尾雌虾,自然温度下让亲虾交尾,获得了5%的平均交尾率;室内定向交尾实验通过控制水温和密度,促使中国对虾交尾,获得了16.9%的平均交尾率。其中,室内交尾的温度实验设计了12、14、16、18℃4个梯度,雌、雄性别比例均为4∶1,x2检验分析表明,4个温度梯度的交尾率存在差异,其中14℃平均交尾率最高,为31.3%,12℃平均交尾率最低,为6.3%。实验结果表明,室外定向交尾的影响因素较多,不容易控制,很难满足建立大量家系的需要;室内定向交尾在14~16℃的水温条件下,采用雌、雄性别比例为4∶1,可获得较好的交尾效果。本实验结果为大规模建立中国对虾全同胞和半同胞家系奠定了基础,为中国对虾进一步育种工作提供了依据。     

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。     

锦鲤尾鳍细胞系(KF-H)的建立

本研究建立了锦鲤(Cyprinus carpio)尾鳍细胞系。染色体数目、核型及DNA含量等实验,发现锦鲤体细胞和锦鲤培养细胞无显著性差异,染色体数目和DNA含量符合比例关系,建立的锦鲤尾鳍细胞系已形成了稳定的遗传性状,命名为KF-H。     

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.     

不同生长阶段斑节对虾消化酶活性变化

通过对斑节对虾不同生长阶段蛋白酶、脂肪酶及淀粉酶活性变化的分析,探讨了斑节对虾在生长过程中对蛋白质、脂肪和碳水化合物的消化利用。结果表明,根据消化酶活性,可将斑节对虾生长分为两个阶段。第1阶段,在体长10～12.5 cm阶段之前,随着个体的增大蛋白酶和脂肪酶活性不断升高;第2阶段,在12.5 cm之后,蛋白酶和脂肪酶活性呈现出一定程度的下降。肝胰腺、胃、肠3种不同消化器官的消化酶活性在不同生长期也不一致,大致上蛋白酶活性从高到低依次为:肝胰腺>胃>肠;脂肪酶活性:肠>肝胰腺>胃;淀粉酶活性:肠>胃>肝胰腺。     

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.     

细鳞鱼核型的初步研究

滦河水系的细鳞鱼(Brachymystax Lenok)二倍体染色体数为2n=92.核型:14M+14SM+64(ST,T),NF=120.并在一个中期分裂相中观察到一条最大的中部着丝点染色体上具有随体.