Effect of dietary vitamin E on growth,immunity and regulation of hepatopancreas nutrition in male oriental river prawn,Macrobrachium nipponense

We evaluated the effects of dietary vitamin E on growth, immunity and regulation of the hepatopancreas in male oriental river prawn, Macrobrachium nipponense. Shrimps were fed 0, 40, 80, 160, 320 or 640 mg vitamin E/kg for 60 days. The 80 mg/kg group had the highest weight gain rate, specific growth rate and lowest feed conversion rate while there were no significant differences in survival rate and hepatosomatic index. The highest crude fat and lowest crude protein content were observed in the 160 mg/kg group. In the hepatopancreas, lysozyme, acid phosphatase and alkaline phosphatase activities were highest in the 160 mg/kg group, while superoxide dismutase, catalase and glutathione peroxidase activities decreased with increasing vitamin E levels. Malondialdehyde content initially decreased then increased with vitamin E levels, whereas the reverse was seen with total antioxidant capacity. Linoleic acid, DPA, DHA, total n‐3 polyunsaturated fatty acid and total polyunsaturated fatty acid first increased then decreased, while EPA and total saturated fatty acid rose with vitamin E levels. Total n‐6 polyunsaturated fatty acid content declined while there were no significant differences in linolenic and total monounsaturated fatty acid content. Following a toxicity test with Aeromonas hydrophila, hepatopancreas ultrastructure revealed that appropriate vitamin E levels promote an increase in mitochondria, endoplasmic reticulum and Golgi bodies, but excess vitamin E can damage cell structure. These results provide evidence that 80–160 mg/kg dietary vitamin E has a positive impact on growth, immunity and regulation of the hepatopancreas in male shrimp.     

镨对青虾卵子孵化的影响

研究了镨(Pr)对青虾（Macrobrachiumnipponense）卵子孵化出Sou状幼体的影响，结果表明：Pr^3 的最佳质量浓度为0.4-1.6mg/L，可孵化离12.4%-20.3%。青虾卵子对Pr^3的饱和吸收量为9.2μg／粒，饱和吸收率为36.8%。     

Growth and metabolic responses of juvenile Macrobrachium nipponense to different dietary carbohydrate levels

It remains controversial whether carbohydrate can be efficiently used by crustaceans. Six isonitrogenous and isolipid diets were formulated containing 50–350 g kg^–1 corn starch and were fed to juvenile prawns (mean weight, 0.133 ± 0.003 g) for 56 days in five replicates. Prawns fed 50–150 g kg^–1 corn starch attained significantly greater weight gain. Digestive enzyme activities were significantly affected by dietary corn starch level. Hepatopancreatic and muscle glycogen levels peaked in prawns fed 350 g kg^–1 and 150 g kg^–1 corn starch content, respectively. Prawns fed 350 g kg^–1 corn starch had a significantly higher haemolymph glucose level than that in the other groups. Hepatopancreatic hexokinase (HK) activity increased significantly as corn starch level was increased. Hepatopancreatic pyruvate kinase (PK) activity of prawns fed the 150 g kg^–1 and 250 g kg^–1 corn starch was significantly higher than that of prawns fed 50 g kg^–1 corn starch. Including carbohydrate in the diet promoted increased lipogenic activities (glucose‐6‐phosphate dehydrogenase and malic enzyme) in the hepatopancreas. Hepatopancreatic HK and PK mRNA expression levels had similar trends with their activities. The 350 g kg^–1 corn starch level induced the highest glucose‐6‐phosphatase and pyruvate carboxylase mRNA expression levels. Overall, moderate metabolic adaptations for using dietary corn starch were detected in Macrobrachium nipponense; however, a high proportion (>150 g kg^–1 ) of corn starch in the diet may reduce growth.     

日本沼虾促雄腺的研究

初步研究了日本沼虾促雄腺的位置、形态、组织结构、变化过程以及其分泌激素的化学性质。结果表明，日本沼虾具有促雄腺1对，位于输精管末端至端壶腹的表面，呈短索状贴于其上，长约2mm，由许多实心腺泡和血窦组成。腺体结构与个体精巢发育周期密切相关，可分为增殖期、合成期和分泌期3个阶段。组织化学研究表明，促雄腺分泌的激素中含有蛋白质，而不含多糖类物质。     

腐植酸钠添加剂在青虾饲料应用中的促生长效果试验

研究了在青虾饲料中添加不同含量的腐植酸钠对青虾生长速度的影响,不同饲料添加剂与腐植酸钠对青虾的促生长效果对比。结果显示：腐植酸钠作为青虾饲料添加剂在饲料中按3‰的量添加效果最佳;不同饲料添加剂中促生长效果以腐植酸钠为最优,其次是甜菜碱、L-肉毒碱、喹乙醇。     

青虾（Macrobrachium nipponense）幼虾趋光性初步研究

以青虾（ Macrobrachium nipponense）幼虾平均体长（13.55±1.96） mm为样本,研究了对7种单色光谱、全色光谱的趋光特性和性别间的差异。实验水簇箱设可更换滤光片的固定光源和捕获趋光幼虾网具,记录5 min内的趋光频率并捕获30 min时的趋光幼虾样本,检测所获样本体长与性别。实验结果表明：（1）410 nm和全色光谱组的幼虾趋光频率最高,555 nm组最低;（2）随光照时间延长幼虾趋光行为减弱,表现出光感疲劳现象;（3）450 nm组的捕获样本中,雌性数占80％,雌雄比4.0达到实验最大值,全色光组的雌性数仅占42.3％,雌雄比0.73为实验最小值;（4）610 nm组捕获样本平均体长最大,410 nm组的平均体长最小,表明发育早期幼虾对短波长敏感,而发育中期的幼虾则对长波长敏感。     

青虾池塘养殖试验报告

利用边坡较缓、淤泥较浅的２个池塘（共计３．３亩），通过人工设置水花生和网片附着物、投喂全价配合饲料、保持中度肥水等水质调节和病害防治措施，进行青虾养殖试验，结果亩产量 １１５．５ ｋｇ，亩利税 １７０９元，投入产出比 １：２．８８。指出池水透明度应保持 ３０～４０ｃｍ。     

钙离子浓度对日本沼虾感光细胞内可溶性Gq蛋白α亚基含量的影响

研究了钙离子浓度对日本沼虾(Macrobrachium nipponense)感光细胞中可溶性Gq蛋白α亚基含量的影响.以暗适应状态日本沼虾的复眼视网膜为材料,分别用高钙溶液、生理溶液、低钙溶液进行孵育,应用SDS-PAGE及免疫印迹技术对其可溶性蛋白粗提取液进行分离和鉴定,并利用Tanon GIS凝胶图像处理系统对蛋白条带的含量进行分析,结果显示:不同钙离子浓度中孵育的日本沼虾感光细胞蛋白的条带数量和分子量大小基本相同.兔抗Gqα多克隆抗体在高钙溶液、生理溶液及低钙溶液处理的日本沼虾感光细胞中均识别了可溶性Gq蛋白α亚基,分子量为42 ku,可溶性Gq蛋白α亚基的含量分别是8.6%、8.4%和7.2%.在暗适应条件下,细胞中可溶性Gq蛋白α亚基的含量与钙离子浓度成正比,这表明钙离子浓度的升高可促进膜结合的Gq蛋白α亚基转化为可溶性的Gq蛋白α亚基.     

Effects of the dietary protein to energy ratio on growth,feed utilization and body composition in Macrobrachium nipponense

Oriental river prawn (Macrobrachium nipponense) has been widely cultured in Asian countries. However, its nutritional studies are very limited. In the present 8‐week study, we investigated the effects of dietary protein to energy ratio (P/E ratio) on the growth, feed utilization and body composition in juvenile M. nipponense (initial weight 0.302 ±0.03 g). Two‐factor experiment was designed and nine semi‐purified diets were formulated to contain three lipid levels (20, 80 and 140 g kg^?1) and three protein levels (330, 380 and 430 g kg^?1), producing P/E ratios from 16.5 to 23.4 mg KJ^?1 protein. The results indicated that the growth, survival rate and protein efficiency were dose dependently improved by the increased dietary lipid, but not dietary protein content. Increased dietary lipid content and/or protein content increased lipid accumulation in whole body, hepatopancreas and muscle, but did not change the feed intake and hepatopancreas weight. In conclusion, our present study indicated that M. nipponense is a species with relatively high‐energy requirement. It could utilize dietary lipid content up to 140 g kg^?1, while the dietary protein with more than 330 g kg^?1 would not promote growth and protein efficiency. Taken together, 330 g kg^?1 dietary protein and 140 g kg^?1 dietary lipid level with P/E ratio 16.49 could be optimum for M. nipponense.     

日本沼虾第一触角感受器的形态和分布

本研究应用扫描电子显微镜对日本沼虾第一触角触鞭上各种感受器的分布情况和形态结构进行了观察。结果表明,雌性和雄性日本沼虾触角感受器在种类、形态和分布上均相似。第一触角分为内、外两鞭,外鞭上具有附鞭。触角上共有四种感受器,分别为化感刚毛（或称嗅毛）、I型简单刚毛、II型简单刚毛和有齿刚毛。化感刚毛上端柔软,顶端无孔,仅着生于附鞭的凹槽内。其它三种感受器在内外两鞭上均有分布。I型简单刚毛通体光滑,顶端逐渐变细,具一顶孔,常伴生II型简单刚毛和有齿刚毛,但长度比后两种的短;II型简单刚毛基部光滑,顶端被鳞片覆盖,且具复杂的孔结构;有齿刚毛有大小两种类型,表面上长有许多齿状突起,齿状突起主要分布于刚毛近顶端1/2~1/3区域内,近基部光滑无齿状突起。有齿刚毛的顶端也被鳞片覆盖,也具复杂的孔结构,结构与II型简单刚毛十分相似。     

日本沼虾体表寄生物对胚胎附着的影响

用扫描电镜技术研究了体表寄生物对日本沼虾（Macrobrachium nipponense)受精卵（胚胎）附着的影响，发现在流产个体1－4对腹肢原肢与内肢的表面密布钟虫类原生动物，这些寄生原生动物影响粘液腺的分泌活动，使其不能正常分泌粘液，受精卵的被膜、卵柄及卵索均不能正常形成，卵与卵之间的摩擦力加大，胚胎供氧困难，最终导致死胎和流产，体表寄生物是造成养殖日本沼虾胚胎提早脱落的重要原因之一。     

青虾“红体病”组织病理学观察

用连续切片的方法对患有红体病的青虾进行组织病理学研究，结果表明患病青虾鳃部、肌肉组织和肝胰腺部位病症比较明显，不同患病阶段组织变形差异显著。鳃片细胞在患病初期表现为胞质收缩，后期则细胞膨胀破裂。细胞内物质外溢，细胞边缘界限不完整；肌肉组织在后期出现肌纤维束之间间隙，且部分肌纤维有断裂的现象；中期肝小叶间隔出现空隙和腺细胞变形，在后期则表现为小叶溃烂。造成青虾因红体病死亡的原因，初期主要是因为鳃片的组织病变导致呼吸困难，进而造成青虾生理异常；后期主要是因为肝胰脏的溃烂造成消化功能全面丧失。     

白洋淀日本沼虾血细胞的初步研究

对取自华北白洋淀种群的日本沼虾(Macrobrachium nipponense)血细胞进行显微形态观察、分类、测量和计数。依据细胞的形态,胞质中颗粒的数量和密度以及细胞的核质比把日本沼虾血细胞分为透明细胞(hyaline cell,HC)、半颗粒细胞(semigranular cell,SGC)和颗粒细胞(granular cell,GC)3类。血细胞大小依次为颗粒细胞>半颗粒细胞>透明细胞。血细胞密度为(1.13±0.50)×106个/mL,其中GC占48.5%,SGC占31.8%,HC占19.7%。并对我国日本沼虾的华南种群、华中种群及白洋淀所在地华北种群的血细胞大小和数量进行了比较。     

维生素C对中华绒螯蟹非特异性免疫的影响

通过在以鱼粉、豆粕、玉米粉和麦麸为主要原料配制而成的每100g基础饲料中分别添加0、250、500、1 000、1 500 mg的VC(以VC多聚磷酸酯为VC源)配制5种试验饲料,对均重为(37.52±2.19)g的中华绒螯蟹进行为期60 d的饲养试验,以酚氧化酶(PO)、抗菌力(Ua)、溶菌酶(UL)、超氧化物歧化酶(SOD)、碱性磷酸酶(AKP)和酸性磷酸酶(ACP)等指标为判据,研究VC对中华绒螯蟹体液免疫因子的影响.结果表明,VC对中华绒螯蟹各组织器官中PO、Ua、UL、SOD、AKP和ACP等活性有显著或极显著的影响(P<0.05或P<0.01),在适宜范围内,随着vc添加量的增加,PO、Ua、UL、AKP和ACP活性显著增强,从而增强中华绒螯蟹的非特异性免疫力,而SOD活性则显著降低(P<0.05),表明VC作为天然抗氧化剂在中华绒螯蟹体内发挥了很大的作用.综上所述,VC作为免疫刺激剂能有效地增强中华绒螯蟹的非特异性免疫力,且VC适宜添加量以500～1 000 mg·(100g)-1饲料为宜.     

复方中草药对青虾免疫功能的影响

将大黄、黄芩、党参、板蓝根等十余味中草药粉碎过筛后制成复方添加剂按1%、2%、3%的比例添加于基础饲料中制成颗粒药饵投喂青虾,测定青虾相关免疫指标的变化。结果表明,青虾血细胞吞噬百分比和吞噬指数、血清溶菌酶活力均显著提高。经嗜水气单胞菌攻毒后,各试验组的免疫保护率也明显提高。在各试验组中以2%的添加量的效果最好。试验证明,该添加剂可显著地提高青虾的免疫功能,能有效地预防嗜水气单胞菌的感染。     

日本沼虾中肠腺细胞的超微结构研究

应用电镜技术研究了日本沼虾中肠腺细胞的类型及超微结构。结果表明：日本沼虾中肠腺上皮细胞大多呈柱状，顶端具有微绒毛，依结构和功能不同可分为Ｒ细胞、Ｆ细胞、Ｂ细胞和Ｅ细胞４种类型。Ｒ细胞具有吸收、贮存营养物质的功能，细胞内含有脂滴、糖原和吞噬咆，内质网、线粒体等细胞器数量少；Ｆ细胞内蛋白酶原合成活动旺盛，粗面内质网极为发达，在数量上比Ｒ细胞多，几乎充满整个细胞；Ｂ细胞微绒毛较短，以胞饮方式吸收营养，在     

乐果对日本沼虾血淋巴溶菌酶与酚氧化酶活力的影响

将日本沼虾暴露于0.0001、0.001、0.01、0.1、1.0 mg/L的乐果溶液中14 d,溶菌酶与酚氧化酶活力均较对照组明显降低,且随乐果浓度的增加和胁迫时间的延长而呈下降趋势.0.0001 mg/L的乐果对日本沼虾的免疫功能即有一定的抑制作用.溶菌酶与酚氧化酶活力可作为日本沼虾亚急性中毒的检测指标.     

复方中草药对青虾肌肉和肝胰脏中几种非特异性免疫因子的影响

以青虾(Macrobrachium nipponense)为试验对象,研究了复方中草药对其肌肉和肝胰脏中几种非特异性免疫因子的影响。结果显示:投喂添加复方中草药的饲料60 d后,与对照组相比,青虾肌肉和肝胰脏中溶菌活性、抗菌活性、酚氧化酶、过氧化物酶活性变化不明显(P>0.05)。肌肉中的血凝活性敏感度低以至无法测出,肝胰脏中的血凝活性试验饲料组显著高于对照组(P<0.05)。肌肉和肝胰脏中的酸性磷酸酶、碱性磷酸酶、超氧化物歧化酶活性显著高于对照组(P<0.05),说明复方中草药对增强青虾免疫活性具有一定的作用。     

Effects of dietary lipid levels on the growth,fatty acid profile and fecundity in the oriental river prawn,Macrobrachium nipponense

An 8‐week feeding trial was conducted to investigate the effects of dietary lipid levels on growth performance, fatty acid profile and fecundity in the oriental river prawn Macrobrachium nipponense. Five isonitrogenous experimental diets were formulated with graded lipid levels [A (5.02%), B (5.98%), C (6.91%), D (7.91%) and E (8.89%) respectively]. The results indicated that the values of body weight gain, specific growth rate, protein efficiency ratio and protein retention presented a similar trend of increasing first and then decreased with increasing dietary lipid levels. Furthermore, prawns fed diets containing 6.91% lipid showed the best values on these parameters among all the treatments. EPA, DHA and n‐3/n‐6PUFA contents showed associated increasing with the increase in lipid deposition of prawn muscle. The activities of hepatopancreatic amylase, protease and lipase were also significantly (p < .05) improved by dietary 6.91% lipid. Increasing dietary lipid levels could not suppress early maturation with no differences detected in berried females throughout the feeding trial. Significant lower relative fecundity may contribute to describing the dietary moderate lipid level (6.91%) could promote the growth of spawners and decrease spawning quantity. The recommendation dietary lipid requirement, estimated by the broken‐line model based on specific growth rate against dietary lipid levels, was 7.19% of the dry matter for M. nipponense.     

Effect of dietary cellulose level on specific dynamic action and ammonia excretion of the prawn Macrobrachium rosenbergii (De Man 1879)

The feeding energetics of the prawn Macrobrachium rosenbergii (De Man 1879) were examined with respect to the effect of dietary fibre. Adult animals were fed semi‐purified diets with 0%, 5%, 10% and 15%α‐cellulose to determine the maximum aerobic scope that could be elicited by the increase in metabolism as specific dynamic action (SDA). The excretion rates of ammonia were also measured. Prawns fed all diets had significantly higher respiration rates after feeding due to SDA. Feed intake was not related to metabolism rate. Both oxygen uptake and ammonia excretion were affected by feed intake, dietary cellulose and time after feeding. SDA was related to dietary fibre, indicated by increments varying from 37% to 386%. O:N ratios were influenced by feed intake, dietary cellulose levels and time after feeding. O:N ratios of between 10 and 49 indicate that the prawns predominately metabolize carbohydrate.