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1.
用6.0×104拷贝、1.2×104拷贝和6.0×103拷贝3种剂量白斑综合症病毒(WSSV)对凡纳滨对虾和斑节对虾进行人工注射感染,比较了两种对虾对WSSV敏感性的差异。结果表明,凡纳滨对虾死亡时间随病毒剂量降低而延长,斑节对虾死亡时间没有明显差异;随病毒剂量的降低,凡纳滨对虾人工注射感染后病毒复制高峰时间显著延长,斑节对虾感染后病毒复制高峰时间相同,WSSV在凡纳滨对虾体内比在斑节对虾体内复制慢。对虾携带WSSV数量最低为3.3×107拷贝.g-1,最高为4.3×108拷贝.g-1。凡纳滨对虾比斑节对虾对WSSV的抵抗性更强。  相似文献   

2.
凡纳滨对虾(Penaeus vannamei)、斑节对虾(Penaeus monodon)、日本对虾(Penaeus japonicus)和刀额新对虾(Metapenaeus ensis)是我国主要对虾养殖品种,具有重要经济价值.对虾,不具有特异性的免疫系统,其非特异性免疫主要通过血细胞吞噬、包囊和形成结节等功能来完成.  相似文献   

3.
对凡纳滨对虾(Litopenaeus vannamei)与点带石斑鱼(Epinephelus malabaricus)进行90 d的混养试验,研究点带石斑鱼混养密度、规格对凡纳滨对虾生长、成活率和产量的影响。结果表明,点带石斑鱼混养密度、规格均对凡纳滨对虾生长、成活率和平均产量的影响有统计学意义(P0.05)。在混养密度相同的条件下,混养小规格点带石斑鱼的凡纳滨对虾成活率比混养大规格点带石斑鱼提高15.1%~23.2%,平均产量比混养大规格点带石斑鱼提高19.0%~40.6%。随着点带石斑鱼混养密度增加,凡纳滨对虾成活率和平均产量呈下降趋势。小规格点带石斑鱼混养密度分别为0.4尾·m-2时,凡纳滨对虾成活率和平均产量最高,分别为66.25%%±7.24%、(1 181.0±101.8)kg,较单一养殖凡纳滨对虾成活率提高5.46%,平均产量提高16.2%;大规格点带石斑鱼混养密度为0.2尾·m-2时,凡纳滨对虾成活率和平均产量最高,分别为(52.04±6.11)%、(959.8±89.1)kg,但较单一养殖凡纳滨对虾成活率下降8.75%,平均产量下降5.88%  相似文献   

4.
凡纳滨对虾(Penaeus vannamei)、斑节对虾(Penaeus monodon)、日本对虾(Penaeus japonicus)和刀额新对虾(Metapenaeus ensis)是我国主要对虾养殖品种,具有重要经济价值。对虾,不具有特异性的免疫系统,其非特异性免疫主要通过血细胞吞噬、包囊和形成结节等功能来完成。近年来,国内外学者应用电镜、  相似文献   

5.
光合细菌对养殖水质及凡纳滨对虾抗病力的影响   总被引:1,自引:0,他引:1  
在凡纳滨对虾养殖环境中人工引入不同浓度的光合细菌,监测氨氮、亚硝酸氮、化学需氧量的变化,15d后测定凡纳滨对虾的AKP、POD、PO、SOD、抗菌、溶菌活力,以及不同光合细菌浓度下凡纳滨对虾的成活率与体重增长率,研究光合细菌对水质和凡纳滨对虾抗病力的影响。结果表明,引入光合细菌可显著降低水体化学需氧量、氨氮含量,并抑制亚硝酸盐氮的产生,提高凡纳滨对虾的抗病力。当光合细菌投放浓度为3×103/mL时,水体中化学需氧量、氨态氮、亚硝酸盐氮含量的均值分别比对照组降低31.59%、43.42%、52.20%,差异显著(P<0.05);对虾的AKP、POD、PO、SOD、抗菌、溶菌活力分别比照组提高31.92%、72.29%、55.56%、31.61%、39.07%、69.51%,差异显著(P<0.05);成活率,体重增长率分别比对照组提高18.67%、34.03%,差异显著(P<0.05)。  相似文献   

6.
以凡纳滨对虾(Litopenaeus vannamei)与金钱鱼(Scatophagus argus)混养池塘和凡纳滨对虾单养池塘为研究对象,对两池塘水体的理化因子及浮游生物进行测定。结果显示:混养池塘水体的溶解氧与单养池塘相比均无显著性差异;混养和单养池塘的化学需氧量(COD)、亚硝酸盐和氨氮的含量在实验过程中均呈现持续上升趋势,但混养池上升趋势较缓,两池塘的上述指标在养殖前期差异不显著,养殖后期有显著差异(P<0.05)。在养殖后期,混养池塘的浮游植物丰度显著大于单养池塘(P<0.05),而浮游动物丰度显著低于单养池塘(P<0.05)。结果表明,混养金钱鱼可有效改善凡纳滨对虾精养池塘的水质,降低亚硝酸盐、氨氮及COD的含量,稳定浮游植物种群结构,控制池塘中浮游动物的过度繁殖。  相似文献   

7.
【目的】探讨高蛋白酵母培养物替代鱼粉对凡纳滨对虾(Litopenaeusvannamei)生长性能、血清生化指标、非特异性免疫力和抗病力的影响。【方法】在基础饲料中分别添加质量分数0、2.5%、5.0%和7.5%酵母培养物(记为Y0、Y2.5、Y5.0和Y7.5组),分别替代质量分数0、10%、20%和30%的鱼粉,配制4种等氮等脂饲料,饲喂凡纳滨对虾(初始体质量0.70±0.03 g)56 d后,测定对虾生长性能、血清生化及免疫酶指标;用哈维氏弧菌(Vibrioharveyi)攻毒,测定对虾累计死亡率。【结果】Y2.5和Y5.0组凡纳滨对虾增重率和特定生长率与Y0组的差异无统计学意义(P 0.05),Y5.0组凡纳滨对虾摄食率显著高于Y0和Y2.5组(P 0.05);Y5.0组凡纳滨对虾血清甘油三酯含量显著低于Y0组(P0.05),Y7.5组凡纳滨对虾血清谷丙转氨酶含量显著高于Y0、Y2.5组(P 0.05),血清总胆固醇显著低于Y0、Y2.5组(P 0.05);酵母培养物替代饲料中20%和30%的鱼粉可显著提高对虾攻毒前肝胰腺超氧化物歧化酶、过氧化物酶活性(P 0.05),Y7.5组对虾肝胰腺丙二醛含量在哈维氏弧菌(Vibrio harveyi)攻毒后显著低于Y0组(P 0.05);攻毒7 d后,Y7.5组凡纳滨对虾累积死亡率显著低于Y0组(P0.05)。【结论】酵母培养物替代鱼粉比例小于20%时,不会显著影响凡纳滨对虾生长性能;替代比例为30%时,生长受抑制。当替代量比例为30%时可显著提高凡纳滨对虾非特异性免疫力和抗病力。  相似文献   

8.
在凡纳滨对虾饲料中分别添加大黄0、0.5、1.0、5.0、10.0和20.0g/kg,研究大黄对凡纳滨对虾(初始体重为0.34±0.004g)生长及非特异性免疫指标的影响。结果表明,大黄对凡纳滨对虾成活率、增重率、特定生长率、饲料系数、蛋白质效率和蛋白质累积率的影响不显著(P>0.05),对全虾和尾肌肉的灰分、脂肪和粗蛋白含量影响显著,全虾的粗蛋白和粗脂肪含量以1.0g/kg组最高(P<0.05),对凡纳滨对虾血清碱性磷酸酶、酸性磷酸酶、酚氧化酶、超氧化物歧化酶、溶菌酶以及血清总蛋白量等的影响显著,溶菌酶活性以1.0g/kg组最高(P<0.05);细菌感染实验中以1.0g/kg组存活率最高(P<0.05)。以非特异性免疫反应指标及感染实验存活率为指标,凡纳滨对虾饲料中大黄的适宜添加量为1.0g/kg。  相似文献   

9.
采用直接测序法研究凡纳滨对虾(Litopenaeus vannamei)过氧化氢酶(CAT)基因的单核苷酸多态性(SNP),并分析得到的基因型与凡纳滨对虾低溶氧耐受性状的关联性,寻找与凡纳滨对虾耐低溶氧性状相关的SNP标记。结果显示:在CAT基因外显子1第155碱基处发现1个SNP位点,为A→G颠换,表现为同义突变。在凡纳滨对虾群体中该位点等位基因A和G的频率分别为0.146和0.854,多态信息含量PIC值为0.218,属于低度多态性,群体在该基因座上符合哈温(Hardy-Weinberg)平衡(P0.05)。关联分析表明,CAT基因SNP位点不同基因型与低溶氧耐受性状关联性有统计学意义(χ~2=9.277,P=0.002),其中AG型在应激耐受组中占优势地位(52.17%)。CAT基因多态性与凡纳滨对虾低溶氧耐受性相关,可作为影响凡纳滨对虾耐低溶氧性状的候选基因,为凡纳滨对虾选育提供分子遗传标记。  相似文献   

10.
将枯草芽孢杆菌、纳豆芽孢杆菌、地衣芽孢杆菌等比例混合,制成芽孢杆菌制剂;将芽孢杆菌制剂与粪肠球菌、嗜酸乳杆菌等比例混合制成复合益生菌制剂;将分别用3种芽孢杆菌发酵的中草药等比例混合制成中草药芽孢杆菌制剂;将分别用5种益生菌发酵的中草药等比例混合,制成中草药复合益生菌制剂。在饲料中分别添加4种益生菌制剂(活菌为2×10~7 cfu/g),研究4种制剂对凡纳滨对虾(Litopenaeus vannamei)生长、抗病力及水质的影响。结果表明:1)4种益生菌制剂均可提高凡纳滨对虾的成活率、增重率和饲料利用率(P0.05),中草药益生菌制剂组的促生长效果优于益生菌制剂组,以中草药复合益生菌制剂组促生长效果为最佳(P0.05);2)4种益生菌制剂均可维持对虾养殖水体p H值、氨态氮和亚硝酸盐含量的稳定(P0.05),中草药益生菌制剂对水质的改良效果优于益生菌制剂(P0.05);3)用1×10~8 cfu/m L的哈维氏弧菌(Vibro harveyi)菌液浴浸泡凡纳滨对虾10 d,凡纳滨对虾的累计死亡率由大到小依次为中草药复合益生菌制剂组(31.11%)、复合益生菌制剂组(35.56%)、中草药芽孢杆菌制剂组(37.78%)、芽孢杆菌制剂组(44.44%)、对照组(93.33%)。在饲料中添加一定比例的中草药复合益生菌制剂可提高凡纳滨对虾的生长指标、改善养殖水体环境、提高对虾的抗病力。  相似文献   

11.
本文对我国养殖的 9种对虾主要形态特征作了简要的描述 ,并根据它们的不同特征把这 9种对虾分成 4个组 :即中国对虾组、斑节对虾组、日本对虾组和凡纳对虾组。对各组间和组内不同种类对虾的形态特征作了比较 ,并根据它们不同的形态特征编出检索表 ,以便于生产上应用。  相似文献   

12.
在建立斑节对虾实验室养殖模式的基础上,对野外采集的有白斑综合症病毒(WSSV)病典型症状的斑节对虾初步纯化其病毒,并进行WSSV的PCR检测,得到WSSV的感染用样品。对健康斑节对虾分别进行浸浴感染,投喂感染和注射感染。对感染死亡个体进行WSSA的PCR检测和细菌检测,证实WSSV感染性和致死性。浸浴感染、投喂感染和注射感染的感染量分别为4mL/L、0.2g/10g虾体、1/2稀释液0.05mL/10g虾体,死亡开始时间分别为16d、42h、28h,三种感染模式最终死亡率100%,从开始死亡到全部死亡延续时间分别为15d、82h、44h。  相似文献   

13.
The influence of Bacillus probiotics on the digestive enzyme activity and the growth of Litopenaeus vannamei were de-termined in this study. The shrimp was treated with five percentages (1.5, 3.0, 4.5, 6.0 and 7.5) of probiotics (Bacillus spp.) supple-mented to the feed and cultured for 45d. The growth measured as the weight gain at the end of culturing was significantly (P<0.05) higher in probiotic-treated shrimps than that of the control (without receiving probiotics). Activities of protease and amylase, two digestive enzymes of the midgut gland and the intestine were significantly (P<0.05) higher in probiotic-treated shrimp than in the control.  相似文献   

14.
15.
The clotting protein (CP) plays important and diverse roles in crustaceans, such as coagulation and lipid transportation. A clotting protein was purified from the hemolymph of Chinese shrimp Fenneropenaeus chinensis (named as Fc-CP) with Q sepharose HP anion-exchange chromatography and phenyl sepharose HP hydrophobic interaction chromatography. Fc-CP was able to form stable clots in vitro in the presence of hemocyte lysate and Ca2+, suggesting that the clotting reaction is catalyzed by a Ca2+-dependent transglutaminase in shrimp hemocytes. The molecular mass of Fc-CP was 380 kDa under non-reducing conditions and 190 kDa under reducing conditions as was determined with SDS-PAGE. CP exists as disulfide-linked homodimers and oligomers. The N-terminal amino acid sequence of Fc-CP was identical to that of shrimps including Penaeus monodon, Farfantepenaeus paulensis and Litopenaeus vannamei; and similar to that of other decapods. The purified Fc-CP was digested with trypsin and verified on an ABI 4700 matrix-assisted laser desorption/ionization tandem time-of-flight (MALDI-TOF/TOF) mass spectrometry. Our results will aid to better understanding the coagulation mechanism of shrimp hemolymph.  相似文献   

16.
Selective breeding of the Pacific white shrimp Litopenaeus vannamei during the last decade has produced new varieties exhibiting high growth rates and disease resistance.However,the identification of new varieties of shrimps from their phenotypic characters is difficult.This study introduces a new approach for identifying varieties of shrimps using molecular markers of microsatellites and mitochondrial control region sequences.The method was employed to identify a new selected variety,Kehai No.1(KH-1),from three representative stocks(control group):Zhengda;Tongwei;and a stock collected from Fujian Province,which is now cultured in mainland China.By pooled genotyping of KH-1 and the control group,five microsatellites showing differences between KH-1 and the control group were screened out.Individual genotyping data confirmed the results from pooled genotyping.The genotyping data for the five microsatellites were applied to the assignment analysis of the KH-1 group and the control group using the partial Bayesian assignment method in GENECLASS2.By sequencing the mitochondrial control regions of individuals from the KH-1 and control group,four haplotypes were observed in the KH-1 group,whereas14 haplotypes were obtained in the control group.By combining the microsatellite assignment analysis with mitochondrial control region analysis,the average accuracy of identification of individuals in the KH-1group and control group reached 89%.The five selected microsatellite loci and mitochondrial control region sequences were highly polymorphic and could be used to distinguish new selected varieties of L.vannamei from other populations cultured in China.  相似文献   

17.
An 8 weeks feeding experiment was conducted to determine the effect of dietary potassium on the growth and physiological acclimation of Pacific white shrimp(Litopenaeus vannamei) reared in diluted seawater(salinity 4). Six semi-purified practical diets containing 0.59, 0.96, 1.26, 1.48, 1.74, and 2.17+ g potassium K per 100 g diet were formulated, respectively. The survival and feed conversion rate did not show significant difference among groups of shrimps given these diets(P0.05). The shrimps fed the diets containing 0.96-1.48 g K+ per 100 g diet gained the highest weight, specific growth rate, and protein efficiency ratio. Their ammonium-N excretion rate as well as hemolymph concentration of Na+ and Cl- were significantly lower than those of the control(P0.05), but a reverse trend was observed for their gill Na+/K+-ATPase. Moreover, the shrimps fed with 1.48 g K+ per 100 g diet were the highest in hemolymph urea level, and the phenoloxidase and lysozyme activities were significantly higher than those of the control(P0.05). The growth and physiological response of the test shrimps suggested that diet containing 1.48 g K+ per 100 g diet improved the growth of L. vannamei in low-salinity seawater, and enhanced the physiological acclimation of the organism.  相似文献   

18.
眼柄粗提物对凡纳滨对虾性分化的影响   总被引:1,自引:0,他引:1  
采用生化方法制备凡纳滨对虾[Litopenaeus(Penaeus)vannamei)]眼柄粗提物,用活体注射法研究不同粗提物剂量对去眼柄凡纳滨对虾卵母细胞直径大小的影响,以检验其性腺抑制素(Gonadinhibiting hormone,GIH)的生物活性;在凡纳滨对虾仔虾后17、22和27 d,分别以不同浓度眼柄粗提物浸泡24 h,结果显示:除0.001个眼柄/mL的GIH浓度外,0.01、0.1和1个眼柄/mL组均显著降低凡纳滨对虾卵母细胞直径(P﹤0.05);浸泡处理后,仔虾后17 d GIH处理组凡纳滨对虾雌性率达70.1%~80.1%;仔虾后22 d GIH处理组雌性率达65.8%~71.7%,各浓度GIH处理组雌性率比对照组(雌雄比例约为1:1)显著提高(P﹤0.05);仔虾后27 d,0.01和1个眼柄/mL处理组雌性率(约58%)略高于对照组,但0.1个眼柄/mL处理组雌性率(73.1%)与对照组相比显著提高(P﹤0.05)。结果表明较低浓度的眼柄粗提物可明显诱导凡纳滨对虾雌性化,在仔虾后22 d前处理效果最佳。  相似文献   

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