淡水小龙虾资源的综合利用及其开发价值

综述了淡水小龙虾的资源状况、养殖前景及其综合利用的产业化开发。     

Effect of combined fish meal : soybean meal ratio,vitamin C and fish oil supplementations in diet on the growth and reproduction of red swamp crayfish,Procambarus clarkii (Crustacea: Decapoda)

Fish meal (FM), vitamin C (VC) and fish oil (FO) play important roles in the growth and reproduction in aquatic animals. To determine the optimum dietary combinations of FM:SM (soybean meal) ratio, VC and FO supplementations for the growth and reproduction of female crayfish Procambarus clarkii, we used the L9 (3³) orthogonal array, which arranged three factors varied at three levels (FM:SM at 1:3, 1:2 and 1:1.5; VC supplementation at 0.02%, 0.04% and 0.06%; FO inclusion at 1.90%, 2.85% and 3.80%). Range analysis showed that the highest weight gain (WG) of the crayfish occurred at FM:SM of 1:1.5, VC supplementation of 0.04% and FO inclusion of 1.90%, and the maximum gonadosomatic index (GSI), egg laying amount (ELA) and spawning rate (SR) were obtained at FM:SM 1:1.5, VC supplementation 0.06% and FO inclusion 3.80%. Analysis of variance indicated that all the three factors had no significant effects on WG. Fish oil supplementation significantly affected GSI, ELA and SR (P<0.05), while FM:SM did not significantly influence any of these indicators. Taking the cost into consideration, we suggest that a dietary FM:SM of 1:3, VC supplementation 0.06% and FO inclusion 3.80% might be the optimal combinations for the reproduction of P. clarkii.     

克氏原螯虾对高温应激的生理学响应

本实验旨在研究高温对克氏原螯虾(Procambarus clarkia)血液生化指标、抗氧化能力以及热休克蛋白70基因表达的影响。实验分别采用30℃和35℃水温进行高温应激试验,应激前(0 h)和在应激后3、6、12、24和48 h分别采集样本,测定血淋巴液中LDH、GLU、TCHO、TP和TG含量,测定肝胰腺T-AOC、CAT、MDA以及HSP70基因的表达变化。结果显示:在高温应激的初级阶段(6 h),克氏原螯虾血淋巴中的TCHO和LD含量急剧上升,而GLU含量持续上升到24 h;TG含量在应激的初级阶段变化不明显,但在6 h后急速上升,在12 h达到最高后开始回落;TP的含量在初级阶段出现下降,然后在12 h恢复至应激前水平。肝胰腺中的MDA含量在应激后持续上升,在24 h后达到最高值,随后下降至应激前水平;T-AOC在应激后3 h上升至最高水平,随后降低;CAT的含量分别在应激后6 h和12 h上升至最高值然后回落。HSP70基因在应激前未检测到有表达,高温应激后3 h即可检测到少量表达,35℃组在6 h出现大量表达,并持续到12 h,随后24 h降低至无法检出;而30℃组在应激6 h后降低至无法检出。结果表明,30℃和35℃高温能引起克氏原螯虾机体产生应激反应,并对机体的生理机能产生影响。     

Response of crayfish, Procambarus clarkii, haemocytes infected by white spot syndrome virus

White spot syndrome virus (WSSV) is a serious pathogen of aquatic crustaceans. Little is known about its transmission in vivo and the immune reaction of its hosts. In this study, the circulating haemocytes of crayfish, Procambarus clarkii, infected by WSSV, and primary haemocyte cultures inoculated with WSSV, were collected and observed by transmission electron microscopy and light microscopy following in situ hybridization. In ultra-thin sections of infected haemocytes, the enveloped virions were seen to be phagocytosed in the cytoplasm and no viral particles were observed in the nuclei. In situ hybridization with WSSV-specific probes also demonstrated that there were no specific positive signals present in the haemocytes. Conversely, strong specific positive signals showed that WSSV replicated in the nuclei of gill cells. As a control, the lymphoid organ of shrimp, Penaeus monodon, infected by WSSV was examined by in situ hybridization which showed that WSSV did not replicate within the tubules of the lymphoid organ. In contrast to previous studies, it is concluded that neither shrimp nor crayfish haemocytes support WSSV replication.     

温度、pH对克氏原螯虾血清酚氧化酶活力及稳定性的影响

以克氏原螯虾(Procam barus clarkii)为材料,研究温度、pH对其血清酚氧化酶活力及稳定性的影响。实验以L-dopa为反应底物,在试验设计的温度范围(20,30,40,50,60,70℃)内,测得酚氧化酶活力的最适温度为20℃,随温度升高酶活力迅速下降,该酶在20~40℃范围内表现出较高的热稳定性,而30℃时最稳定;该酶的最适pH 7.0,在pH 6.0和7.0的缓冲系统中表现出较强的稳定性。     

克氏螯虾染色体研究

本文以克氏螯虾精巢为材料，用改良常规气干法进行染色体制片并显微照相，观察结果表明，克氏螯虾精母细胞染色体数为９４，中期染色体呈颗粒状。     

WSSV口服卵黄抗体的制备及在螯虾中的应用

将提纯的WSSV接种于蛋鸡后获得了高效价的IgY(卵黄抗体),与一定比例的保护剂混合后,瞬间喷雾干燥制成干粉其效价基本维持不变。在以螯虾为实验模型的攻毒及治疗试验结果表明:饲料中0.1%的IgY含量能在一定程度上延缓螯虾死亡时间,而0.2%的IgY含量则能够使螯虾的最终死亡率从100%降至30%左右。这表明WSSV特异性IgY制剂是安全有效的抗WSSV感染的的新型生物制剂。     

克氏原螯虾对饲料中磷的需求量

以磷酸二氢钙为磷源,制成磷水平为0.83％、1.07％、1.25％、1.38％、1.59％、1.82％和2.03％的7种饲料,并以此饲料投喂克氏原螯虾幼虾(5.02±0.51 g)70 d.试验结果表明:饲料磷水平对克氏原螯虾的增重率、特定生长率、饲料系数影响显著,随着磷水平的增加,增重率和特定生长率逐渐升高,当磷水平为1.82％时达到最大,然后随着饲料磷含量的继续增加,这些指标逐渐降低;饲料系数的变化趋势与增重率和特定生长率相反;试验各组间成活率没有显著差异.全虾粗灰分和磷含量与饲料磷水平呈正相关;随着磷水平的升高,全虾粗脂肪含量呈下降的趋势;肝胰腺碱性磷酸酶活性随磷水平的升高而显著降低;以增重率和特定生长率为评价指标,经过折线模型分析得出,克氏原螯虾最适磷需求量分别为1.84％和1.80％.     

Effects of Harvest Period on the Production of White River Crayfish,Procambarus acutus acutus

Abstract

Crayfish harvest was initiated at a cool water temperature (15°C) and warm water temperature (20°C) from culture ponds (0.1 ha) with a resident population of white river crayfish, Procambarus acutus acutus.Crayfish were harvested for 24 days for a total of 1,977 trap-days/ha (March 9-May 12, 2000 from the cool-harvest treatment and May 5-June 15, 2000 from the warm-harvest treatment). The mean total length (TL) and production of harvested white river crayfish (WRC) was similar between treatments. The population structures of WRC from the cool and warm periods of harvest were substantially different; large WRC (≤100 mm TL) from the cool-harvest period were 3.1 times more abundant than large WRC during the warm-harvest period. A similar number of small WRC were harvested from the two treatments; however, those small WRC harvested during the warm period was significantly longer than the small WRC during the cool-harvest period. The estimated large WRC biomass contribution to the total harvest from the cool-harvest period was 37% in comparison to 15% during the warm-harvest period. The estimated dollar value of the production during the cool-harvest period was 40% more than that from the warm-harvest period.     

不同地区克氏原螯虾群体的形态差异分析

运用3种多元统计方法,对江苏、安徽、山东和湖北4个不同地区克氏原螯虾（Procambarus clarkii）野生群体的13个形态比例参数进行比较研究。聚类分析结果显示,山东和江苏2个克氏原螯虾群体之间的形态最为接近,而与湖北和安徽群体间趋异程度逐渐增大。主成分分析中,雌性群体贡献率分别是主成分1为46.104%、主成...