性早熟中华绒螯蟹肝胰腺与性腺的酸性和碱性磷酸酶活性

采用磷酸苯二钠法在520nm波长测定了未成熟、早熟和正常成熟中华绒螯蟹肝胰腺与性腺中的酸性磷酸酶（ACP）和碱性磷酸酶（ALP）。结果表明：（1）各组蟹肝胰腺ACP和ALP活性都显著高于性腺;（2）早熟蟹肝胰腺中ACP活性都显著高于未成熟蟹而低于正常成熟蟹,在各发育阶段没有性别差异,但是,早熟雌蟹和正常成熟雌蟹卵巢中ACP活性都较早熟雄蟹和正常雄蟹精巢低,早熟与正常成熟个体没有差异;（3）早熟雌蟹肝胰腺ALP活性显著高于未成熟和正常成熟雌蟹,而与三组雄蟹处于同一水平,但是,早熟和正常成熟雌雄蟹的性腺中ALP活性没有显著差异。由此得出结论：（1）性腺发育所需营养物质的动员或合成主要与肝胰腺ACP有关;（2）性早熟的发生与肝胰腺中ACP和ALP活性的显著升高有关。     

沉水植物对中华绒螯蟹生长和非特异性免疫力的影响

从东太湖采集伊乐藻(Elodea canadensis)、金鱼藻(Ceratophyllum demersum)、轮叶黑藻(Hydrilla verticilla-ta)、苦草(Vallisneria natans)、马来眼子菜(Potamogeton malaianus)5种沉水植物分别制成干粉。在基础饲料中添加15%的干粉形成5种不同的配合饲料,分别饲喂体重为(9.37±0.15)g的中华绒螯蟹(Eriocheir sinensis)60 d,分析沉水植物对中华绒螯蟹生长和非特异性免疫力的影响。结果显示:马来眼子菜组的中华绒螯蟹平均增重率显著低于对照组(P<0.05),饲料系数显著高于对照组(P<0.05),其余4种沉水植物组的平均增重率和饲料系数与对照组无显著差异(P>0.05);各组成活率、肥满度及肝体比差异不显著(P>0.05)。沉水植物各组的蟹血清超氧化物歧化酶活力显著高于对照组(P<0.05);与对照组相比,轮叶黑藻组、伊乐藻组和苦草组的中华绒螯蟹血清溶菌酶活性显著升高(P<0.05),金鱼藻组和马来眼子菜组则差异不显著(P>0.05);除马来眼子菜组降低外,其余4种沉水植物组中华绒螯蟹对嗜水气单胞菌的抵抗力强于对照组。因此,除马来眼子菜以外的4种沉水植物对中华绒螯蟹的生长性能无明显的促进作用,但可在一定程度上提高其非特异性免疫力。     

Study on the nutritional quality of ecologically bred Chinese mitten crabs with different body weights

To provide basic nutritional data and theoretical support for the processing and comprehensive utilization of the Chinese mitten crab, we performed a systematic study of the nutritional components of three edible parts, namely the hepatopancreas, gonads and abdominal muscle, of three groups of animals differing in body mass: 75.55 ± 1.56 g, 100.24 ± 2.04 g and 162.27 ± 3.44 g. The results showed that with a greater body mass, the water content was higher, the protein and ash contents were first higher and then lower, and the fat content was first lower and then higher. Amino acids (AAs), essential AAs (EAAs) and the EAA/AA ratio were first higher and then lower, all reaching the standard for high‐quality protein. The most limiting AA was valine. The EAA index was greater than 97 for all three edible parts of the medium‐sized crabs, indicating that crabs in this size group had very high nutritional value. The numbers of detected fatty acids were the same among the edible parts and the three size groups of the river crabs. Among the mineral elements measured, Ca, K and Na were the most abundant and showed a trend of first being higher and then being lower with a larger crab size. Although heavy metals were detected, the Cr, Pb and Cd levels were all within the permissible limits. Therefore, the nutritional quality of the three edible parts was greater for medium‐sized river crabs than for small and large mitten crabs.     

中华绒螯蟹“六月黄”与成蟹肝胰腺营养成分比较

对同一年度、同一饲养环境下的中华绒螯蟹"六月黄"和后期成蟹雌、雄个体肝胰腺组织的营养成分进行了测定和比较分析。结果显示,"六月黄"的肥满度与雌性成蟹间没有显著性差异(P0.05),但肝胰腺指数极显著高于成蟹(P0.01)。"六月黄"肝胰腺中水分和灰分的含量极显著高于成蟹(P0.01),而粗脂肪含量极显著低于成蟹(P0.01),两种蟹的粗蛋白质含量没有显著差异(P0.05)。在检测到的17种氨基酸中,除"六月黄"雄蟹肝胰腺中丙氨酸的含量显著低于其雌蟹及雌、雄成蟹外(P0.05),其他16种氨基酸在"六月黄"与成蟹间均不存在显著差异(P0.05)。"六月黄"和成蟹的肝胰腺中含量最高的4种脂肪酸均为C18:1n9c、C18:2n6c、C16:0和C16:1,其总和分别占"六月黄"和成蟹肝胰腺中总脂肪酸的72.13%和69.02%(雌、雄蟹平均值)。"六月黄"的饱和脂肪酸总量显著低于成蟹(P0.05),但其单不饱和脂肪酸总量(ΣMUFA)和多不饱和脂肪酸总量(ΣPUFA)均显著高于成蟹(P0.05)。"六月黄"肝胰腺中Σn-6 PUFA的含量也极显著高于成蟹(P0.01),而Σn-3 PUFA含量二者不存在显著差异,因此"六月黄"的Σn-6/Σn-3 PUFA比率(1.42～1.44)低于成蟹(0.85～0.92)。结果表明,从总体上看,"六月黄"的营养价值较高,其肝胰腺的营养品质好于成蟹,"六月黄"养殖具有一定的产业发展前景。     

枯草芽孢杆菌基因组DNA对中华绒螯蟹非特异性免疫因子的影响

将枯草芽孢杆菌(Bacillus subtzlis)基因组DNA按5、20和80μg/kg剂量体腔注射中华绒螯蟹(Eriocheir sinensis)(约0.1 mL/只),设注射等体积TE缓冲液为对照组,分别在第1、3、5、7天采样,测定该细菌DNA对中华绒螯蟹的免疫刺激作用。结果显示:注射上述3种剂量的枯草芽孢杆菌基因组DNA均能不同程度地提高中华绒螯蟹的THC、血细胞呼吸爆发活性和血清PO、ACP活性,试验组蟹的上述免疫指标的活性显著高于对照组(P<0.05),并以20μg/kg体重剂量的刺激效果最好;但试验剂量的细菌DNA对血清ALP活性无显著影响(P>0.05)。     

环境条件对中华绒螯蟹大眼幼体蜕壳生长的影响

试验结果表明,黑暗条件下大眼幼体蜕壳数量少、成活率低;光照可刺激并促进大眼幼体的蜕壳与生长,但长时间光照会影响Ⅰ期到Ⅳ期幼蟹的蜕壳生长;泥土和隐蔽物作为栖息环境有利于提高中华绒螯蟹幼体的成活率;苗种质量是提高中华绒螯蟹大眼幼体到Ⅳ期幼蟹成活率的关键。     

洪湖低湖田改造池塘河蟹养殖技术研究

在洪湖湖滨地区筛选了4种当地主要的河蟹(Eriocheir sinensis)养殖方式,对池塘与水源的环境因子进行了监测比较,分析各因子对河蟹收获参数的影响。结果显示:7—10月中,8月水温和氨氮含量最高,各池塘水体理化指标月平均值无显著差异;各池塘水草生物量逐月急剧下降,至10月底基本消失,其月平均值与成蟹体重、回捕率及特定生长率显著负相关。高温季节是防止河蟹氨氮中毒死亡的关键时期;水草调节水体营养、稳定底质、吸附水体悬浮质的功能对河蟹存活及生长有重要作用。当地优势池塘养殖方式为:放养规格约5 g/ind.,密度16875 ind./ha,水草移栽以伊乐藻为主,搭配其它种类,覆盖率约为60%,动物性饵料投喂比例约为66%,螺蛳投喂量约3638 kg/ha。     

渔光一体养殖模式对中华绒螯蟹肝胰腺和性腺气味品质的影响

渔光一体养殖模式(photovoltaic fishery breeding mode, PM)是一种采用水下养殖、水上发电的新兴环保养殖模式。本研究比较了渔光一体养殖模式与普通池塘养殖模式(common pond breeding mode, CM)养殖中华绒螯蟹(Eriocheir sinensis)在基本营养成分、感官评价和气味品质等方面的差异。对雌蟹肝胰腺和性腺进行人工及电子感官评价,测定挥发性物质的含量,并对气味品质进行综合评价。结果表明,渔光一体养殖模式能提高雌蟹的性腺指数、增加粗蛋白和粗脂肪含量;PM组肝胰腺表现青草味,电子鼻的响应值最高,PM组性腺的青草味和油脂味更明显;在肝胰腺中,鉴定出44种(PM组)和33种(CM组)物质,PM组总挥发性物质的含量[(70.53±2.91) ng/g]显著高于CM组[(16.63±0.73) ng/g](P<0.05),是CM组的4.2倍,其中油脂味和青草味的物质含量更高;而在性腺中,鉴定出了31种(PM组)和47种(CM组)物质,PM组和CM组总挥发性物质含量分别为(68.80±1.86) ng/g和(71.50±4.17)...     

不同生态环境中华绒螯蟹肉脂品质的比较

选取长江野生、湖泊放流、网围养殖及池塘养殖的中华绒螯蟹成蟹各10只,雌、雄各半,对其进行62个肉脂品质参数的测算。可食部分占体重的29.79%~38.60%,可食部分蛋白含量和粗脂肪含量分别为15.45%~20.32%和8.52%~17.33%,含水量为56.70%~70.30%;必需氨基酸和鲜味氨基酸分别占可食部分的5.29%~7.22%和6.40%~7.91%,氨基酸总量占13.48%~17.57%;可食部分饱和脂肪酸含量约为0.80%~1.71%;不饱和脂肪酸含量约为3.61%~9.29%;高不饱和脂肪酸含量约为0.65%~2.79%;脂肪酸总含量约为4.41%~10.96%。组内雌、雄可食部分比例、粗脂肪、灰分、脂肪酸、微量元素等参数差异较小;水分、粗蛋白、氨基酸等参数差异较大,粗蛋白、氨基酸各有显著差异的参数值均为雄蟹小于雌蟹。同性别不同生态环境成蟹粗蛋白、氨基酸各参数的差异较小;可食部分比例、粗脂肪、水分、灰分、脂肪酸、矿质元素等参数差异较大。综合均值比较结果和实践经验分别选取13个和16个参数,对4组雄蟹、4组雌蟹进行判别,结果表明所选取参数可较好反映中华绒螯蟹肉脂品质的差异。用62个参数分别对4组雄蟹、4组雌蟹进行聚类分析,从总体上反映了不同生态环境中华绒螯蟹的肉脂品质和其相互关系。     

Purification and characterization of a new reovirus from the Chinese mitten crab, Eriocheir sinensis

A new reovirus was recently isolated from a freshwater crab, the Chinese mitten crab, Eriocheir sinensis, in China. The complete viral particles are 55 nm in diameter, icosahedral, non-enveloped and have a mean buoyant density of 1.39 g cm(-3) in CsCl gradient. The viral genome is composed of 12 pieces of dsRNA with an electrophoretic pattern of 3/4/2/3. This virus infects connective tissue of the gills, gut and hepatopancreas. Partial cDNA cloning and sequence analysis showed that the RNA-dependent RNA polymerase is located in the first RNA segment. From its biochemical, ultrastructural and physicochemical properties, this virus is quite different from the genus Aquareovirus (Reoviridae). It may represent a new genus of Reoviridae, different from the other crab reoviruses, P and W(2).     

Pectin plays a role in restricting the utilization of rapeseed meal by Chinese mitten crab,Eriocheir sinensis

The present study aims to assess the anti‐nutritional effect of pectin and to better understand rapeseed meal (RSM) as a feed ingredient for Chinese mitten crab, Eriocheir sinensis. A semipurified diet containing 280 g/kg fish meal was formulated as a control diet (D_F). A second diet (D_P) was supplemented with 26.7 g/kg pectin; the amount was estimated to be equal to that in the third diet (D_R), which was formulated to include 400 g/kg RSM. Another diet (D_RPase) was supplemented with 12 g/kg pectinase based on D_R in which pectin was degraded by pectinase. The diets were randomly fed to twelve tanks of the crab for 8 weeks. Compared with the crabs fed D_F, the specific growth rate, protein efficiency ratio, apparent digestibility coefficients (ADC) of dry matter and protein, activity of aspartate transaminase (AST) and trypsin (TP), and high‐density lipoprotein (HDL) in the serum decreased significantly in the crabs fed D_R; the ADC of dry matter, activity of AST and serum HDL decreased significantly in the crabs fed D_p, but they were higher than in the crabs fed D_R. Compared with the crabs fed D_R, the ADC of dry matter, activity of AST and TP, and serum HDL increased significantly in the crabs fed D_RPase. The mRNA expression activity of both Es‐pl44 and Es‐pp1 was D_F < D_P < D_RPase < D_R. These results indicate that pectin contributed to low utilization of RSM in Chinese mitten crab.     

中华绒螯蟹“蟹黄”与“蟹膏”的营养成分比较分析

本试验对中华绒螯蟹"蟹黄"与"蟹膏"的粗蛋白、氨基酸、粗脂肪、脂肪酸、卵磷脂和维生素等营养成分进行了测定分析。试验结果表明,蟹黄与蟹膏中的粗蛋白质含量为29.79%和9.64%,蟹黄显著高于蟹膏(P0.05);至少共含有17种氨基酸,蟹黄中的必需氨基酸显著高于蟹膏(P0.05),4种致鲜氨基酸比例明显高于蟹膏(P0.05);蟹黄、蟹膏中粗脂肪含量为44.3%和34.9%,差异不显著(P0.05),不饱和脂肪酸含量丰富,蟹黄高于蟹膏,差异不显著(P0.05);蟹黄中卵磷脂、维生素A、D、E的含量均显著高于蟹膏(P0.05)。试验表明,蟹黄比蟹膏具有更高的营养与食用价值。     

虫草培养基残余体在中华绒螯蟹饲料中的适宜添加量

在基础饲料中分别添加0.25%、0.5%、1.0%、2.0%、4.0%、8.0%、16.0%的虫草培养基残余体(简称虫草基),饲喂规格为(4.0±1.0)g的中华绒螯蟹(Eriocheir sinensis)75 d,通过测定其生长及非特异性免疫指标,以确定虫草基的适宜添加量。结果显示:与基础饲料组比较,0.5%和1.0%添加组平均增重率(WGR)、肥满度(CF)、成活率(SR)显著提高(P<0.05),饲料系数(FC)显著降低(P<0.05);除肥满度(CF)外,4.0%、8.0%、16.0%添加组的生长指标有所下降。低剂量虫草基添加组能提高中华绒螯蟹血淋巴及肝胰腺超氧化物歧化酶(SOD)、溶菌酶(LSZ)、酸性磷酸酶(ACP)、碱性磷酸酶(ALP)活性,其中,0.5%与1.0%添加组的SOD、LSZ、ACP和ALP水平均达显著水平(P<0.05);但当虫草基添加量超过2.0%时,中华绒螯蟹的非特异性免疫力逐渐下降。嗜水气单胞菌(Aeromonas hydrophila AHJ-1)攻毒试验证实,试验组的免疫保护率明显提高,0.5%添加组免疫保护率达100%。综上所述,虫草基作为中华绒螯蟹饲料添加剂的适宜添加量为0.5%～1.0%。     

中华绒螯蟹种苗静水土池塘培育技术研究Ⅲ——室内育苗和土池育苗经济效益和生态效益的比较

用１０００ｍ３水体的室内育苗池和６口海水土池塘（计１９ｈｍ２）培育中华绒螯蟹（Ｅｒｉｏｃｈｅｉｒｓｉｎｅｎｓｉｓ）苗,比较两种河蟹人工繁殖技术的生态效益和经济效益。经３５天培育表明,土池培育１ｋｇ大眼幼体可获利２０６３元,比室内育苗获利（３９３元）高４２倍;产出投入比（２０７）比室内育苗（１３３）高４５７７％。若采用土池育河蟹苗,每年至少可以少排放各种化学药物４２０ｔ。     

长江和辽河水系中华绒螯蟹湖泊放养生长性能的比较

对长江水系和辽河水系中华绒螯蟹（Eriocheir.sinensis)在长江下游湖泊生长性能研究的结果：（1）生长速度在3－8月长江蟹稍低于辽河蟹,但差异不显著（P＞0．05）;9－10月长江蟹则快于辽河蟹,差异极显著（P＜0．01）。（2）青春期蜕壳时间辽河蟹比长江蟹提前30－40d,生殖洄游期也相应提前30－40d。（3）养成的商品蟹规格、增重倍数和回捕率,长江蟹优于辽河蟹,差异极显著（P＜0．01）。综合分析认为,长江蟹在长江下游湖泊的生长性能指标优于辽河蟹。     

Comparative study on the nutrition composition of adult male Chinese mitten crab (Eriocheir sinensis) with different coloured hepatopancreases

High lethality of white hepatopancreas syndrome has caused large economic loss of Chinese mitten crab (Eriocheir sinensis). Hepatopancreas colour of diseased crabs is gradually lighter, turning from golden yellow to yellow‐white to white. This study investigated composition of conventional nutrients in three edible parts of different coloured hepatopancreases of adult males, including normal yellow hepatopancreas group (Control), yellow‐white hepatopancreas group (YWH) and white hepatopancreas group (WH). No significant differences were observed in tissue indices and total edible yield among three crab types; however, condition factor level in crabs of YWH and WH was significantly lower. Dry matter content was significantly reduced in crabs of WH, especially crude fat level of hepatopancreas in WH males. Levels of all the amino acids of WH crabs in muscles and gonads were significantly lower than that of control. Proportion of saturated fatty acids and monounsaturated fatty acids were much lower in hepatopancreas of WH crabs than those of control, while proportion of polyunsaturated fatty acids and highly unsaturated fatty acids were significantly higher. Overall, YWH and WH do not affect growth. WH crabs showed poor nutritional quality, and nutritional value of YWH was in the middle as transition state between control and WH.     

对中华绒螯蟹生态育苗池中桡足类控制的初步研究

比较了蛛虫速灭、鱼虫恨和强力混杀3种渔药对桡足类和中华绒螯蟹溞状幼体的急性毒性。试验结果表明,蛛虫速灭对桡足类的96h半致死添加量为0.011mL/m3,鱼虫恨为0.036mL/m3,强力混杀精为0.014mL/m3,蛛虫速灭对桡足类的杀灭能力最强;对中华绒螯蟹溞状幼体Ⅰ期的急性毒性鱼虫恨最大,蛛虫速灭最小。蛛虫速灭在0.18～0.20mL/m3的剂量下,对溞状幼体毒性低,幼体能正常变态,可用于蟹苗池桡足类的控制。强力混杀精对桡足类和中华绒螯蟹溞状幼体的毒性很接近,鱼虫恨对中华绒螯蟹溞状幼体的毒性大于对桡足类的毒性,两者均不适宜在中华绒螯蟹生态池控制桡足类。     

中华绒螯蟹肝胰腺白化症的病因研究

2002年10月以来,通过逐户访问及调查问卷的形式对2001～2002年东太湖中华绒螯蟹(Eriocheir sinensis)养殖区"白膏症"发病症状、扣蟹的来源、投饵模式、水草覆盖率、螺蛳投入量、底泥状况、回捕率、产量等进行较为系统的调查。同时对病蟹进行寄生虫检查、病原微生物分离、回接攻毒及病变组织的电镜观察等病原学研究,结果未发现致病性生物。调查结果表明,中华绒螯蟹"白膏症"的发病率雄蟹显著高于雌蟹,其症状为甲壳发黄,头胸甲腹面下肝区发白色或青黑色,肝胰腺由正常的橘黄色变成淡黄或白色;症状严重的病蟹胸腔积水,肌肉松驰萎缩,肝胰腺呈糜烂状,鳃丝发黑。调查结果显示,"白膏症"的发生与饵料的投喂量、动植物饵料之比及水环境有着密切的联系。根据该病的主要症状及发病原因,认为该病应命名为中华绒螯蟹肝胰腺白化症。