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1.
将经过不同酶解方式处理的肽聚糖制剂配制成饲料投喂凡纳滨对虾(Litopenaeus vannamei),测定不同肽聚糖对对虾血清酚氧化酶和酸性磷酸酶的影响并分析不同酶解处理组肽聚糖制剂中的成分及其含量。肽聚糖制剂成分分析结果显示,经72h溶菌酶水解的肽聚糖制剂的低分子量肽聚糖含量较经过24h水解的肽聚糖制剂高,且蛋白酶的水解作用可促进溶菌酶的水解作用。对虾血清酶活力结果显示,对于提高对虾的酚氧化酶及酸性磷酸酶活力,酶解后的肽聚糖制剂比未经酶解的肽聚糖制剂效果明显,且含有较多低分子量肽聚糖的制剂组的效果优于含有较少低分子量肽聚糖的制剂组。实验结果表明,肽聚糖的免疫增强活性与肽聚糖分子量的大小相关,肽聚糖制剂中低聚糖含量的增加会提高其免疫增强效果。[中国水产科学,2006,13(4):631—636]  相似文献   

2.
肽聚糖制剂对南美白对虾体液免疫因子的影响   总被引:19,自引:4,他引:15  
按一定梯度配制5种含不同水平肽聚糖制剂的饲料,投喂南美白对虾(Litopenaeus vannamei),35 d后取实验对虾血样,用于测定血清中酚氧化酶活力、磷酸酶活力、溶菌活力及超氧化物歧化酶活力.结果显示,饲料中肽聚糖质量分数为500×10-6的实验组,对虾血清中酚氧化酶活力最高,肽聚糖质量分数为2 500×10-6的实验组,对虾血清中酸性磷酸酶与碱性磷酸酶活力最高,肽聚糖对对虾的血清溶菌活力影响不明显(P>0.05).由此表明饲料中添加适量(质量分数500×10-6左右)的肽聚糖制剂可使对虾体液免疫因子总体活力达到较高水平,饲料中肽聚糖制剂含量过高对对虾非特异免疫力的作用效果反而不佳.南美白对虾血清中酚氧化酶活力对饲料中肽聚糖含量变化较敏感,可作为肽聚糖使用效果的评价指标之一.  相似文献   

3.
中国明对虾C 型凝集素基因(Fclectin)的重组表达及活性分析   总被引:1,自引:1,他引:0  
研究拟通过分析对虾C型凝集素的活性特点,探讨其在对虾先天免疫应答过程中的潜在功能以及在养殖生产实践中的应用。实验利用原核表达系统对中国明对虾C-型凝集素基因的两个串联的糖识别结构域(carbohydrate recognition domain,CRD)进行了重组表达,并通过纯化复性获得了重组目的蛋白(rFclectin-CRD1和rFclectin-CRD2)。活性分析结果显示,重组目的蛋白对多种病原菌有凝集和抑制生长的作用,并且具有Ca2+依赖活性;其凝集活性可被半乳糖、肽聚糖、脂多糖等多种病原相关分子模式所抑制,研究结果证实,Fclectin是一种典型的C-型凝集素,它可能作为中国明对虾先天免疫中重要的模式识别受体,在一定程度上参与了机体应答病原微生物的防御过程。  相似文献   

4.
对虾养殖业是技术含量非常高的行业。由于养殖池塘水体大,情况复杂,对虾发病是池塘水环境因子和生物因子的综合体现。很多时候难以用肉眼确诊对虾的病情、病原,即使确诊了,要对症下药,用哪种药、用多少、效果如何,也难以有十分把握治好病。因此,预防疾病的发生十分重要。  相似文献   

5.
对虾Toll受体及其在虾类营养免疫评价中的应用   总被引:2,自引:1,他引:1  
Toll受体是一类跨膜蛋白,其胞外区能够识别仅表达在病原微生物上的高度保守的结构基序(motifs)——病原相关的分子模式(pathogen-associated molecular patterns,PAMPs),并将病原入侵的信号传递到细胞内,诱导产生一系列的免疫效应因子和免疫反应。Toll受体是机体对入侵病原微生物产生免疫效应的关键分子。多种对虾中存在Toll受体,但对虾Toll受体在虾类营养免疫研究中的应用尚未得到发掘。本文综述了Toll信号途径及对虾Toll受体的研究进展,并探讨了Toll受体在虾类营养免疫评价中的应用价值,认为对虾Toll受体表达量的变化可以反映机体对入侵病原识别的灵敏性,在今后的营养免疫学研究中具有重要价值,并提出了今后对虾Toll受体研究的方向。  相似文献   

6.
脂多糖作为免疫增强剂常用于免疫学研究和临床医学中,在海水养殖病害防治中应用较少,已有研究证明,脂多糖可提高对虾血细胞的吞噬活性和贻贝等的酚氧化活力。有关脂多糖对大菱鲆血清中的溶菌酶的影响,国内外尚未见报道。溶菌酶是一种重要的非特异性防御因子,是鱼类生理防御水平的重要标志,也可以体现病原菌及其他环境因素对鱼体健康的影响。  相似文献   

7.
凡纳滨对虾又称南美白对虾,为提高凡纳滨对虾人工育苗质量关键技术,建立了凡纳滨对虾规模化令人工繁育、连续传代和无特定病原繁育技术体系。  相似文献   

8.
为有效地进行凡纳滨对虾病害防治和健康养殖,探究对虾天然免疫机制,为其免疫防控提供新思路,实验根据本课题组前期转录组结果提示,在凡纳滨对虾血细胞中克隆获得了一个新的C型凝集素基因(LvLc2, GenBank登录号KR020738)。生物信息学分析显示,LvLc2的ORF区全长465 bp,编码154个氨基酸(aa),5′-UTR为11 bp,3′-UTR为126 bp;其预测的分子量为17.16 ku,理论等电点为4.54;推断其氨基端含有一个由17个aa组成的信号肽序列,羧基端含有一个保守的糖识别结构域(CRD)。该基因在凡纳滨对虾各种组织中有不同程度的表达,其中在肠道中表达量最高,其次为胃、肝胰腺、血细胞等组织或细胞,在肌肉中表达量最低。利用脂多糖(LPS)和肽聚糖(PGN)刺激对虾后,比较分析了LvLc2的表达变化特征,不同类型的病原表面多糖可在刺激后不同时期引发LvLc2基因的应答改变,表明其具有潜在的广谱应答模式,同时针对不同病原又具有不同的表达特征,显示了其识别结合和间接免疫效应的差异。对其作用特征的探讨有助于更好地了解对虾C型凝集素在病原感染过程中的功能和作用机制。研究结果为深入探讨对虾天然免疫调控机制提供了参考,在对虾健康养殖及病害防治方面具有潜在的应用价值。  相似文献   

9.
白斑综合征病毒感染与对虾的免疫防御反应   总被引:2,自引:1,他引:1  
对虾白斑综合征病毒(WSSV)感染对虾后,最典型的免疫反应是对虾开放循环系统的血淋巴细胞数量急剧下降,血淋巴凝结功能下降,感染部位聚集了大量的血淋巴细胞,且以颗粒细胞为主。WSSV可感染对虾颗粒细胞和小颗粒细胞,其中小颗粒细胞感染率高、感染速率快,感染后大颗粒细胞占血细胞总数的比例可增加到50%;血淋巴中的总糖、总碳水化合物、总蛋白和游离氨基酸显著提高,超氧化物歧化酶、过氧化氢酶和诱导性一氧化氮合成酶的活性显著降低。自然状态下广泛存在WSSV潜伏感染,潜伏感染的存在会导致存在免疫反应情况下的感染复发,并且有助于病毒的传播;不同WSSV感染状态下过氧化物(POD)差异显著,其平均值由大到小依次为:潜伏感染虾样、中度感染虾样、严重感染虾样。而其抗菌活性(UA)、溶菌活性(UL)、酶氧化酶活性(PO)、碱性磷酸酶(ALP)和凝集效价(HAT)差异不显著;潜伏感染个体对再次接种WSSV有“类免疫应答”的抗性,这种抗性不是来源于发病期对虾的天然抗性,而是WSSV感染后的一种免疫系统增强。宿主细胞凋亡可能是感染对虾在高温时反而维持较高成活率的主要机制。免疫增强剂可对对虾防御WSSV感染产生影响,脂多糖、葡聚糖、肽聚糖、岩藻依聚糖和双链核糖核酸都已被证实可提高对虾抗病毒感染的免疫保护。WSSV主要囊膜蛋白VP28可诱导对虾对WSSV感染产生抗性降低累积死亡率,高效价的病毒抗血清具有良好的保护作用;对虾抗菌肽也可通过抑制病毒的复制而起保护作用。  相似文献   

10.
2013年5月,美国亚利桑那大学水产病理实验室(UAZ-APL)定义EMS病原为副溶血弧菌Vibrioparahaemolyticus的特异菌株,该菌株能够产生毒素并诱导健康对虾致病;但是,此病原会在冰冻和解冻的过程中失活;感染AHPNS病原的对虾不会对人类健康造成负面影响。  相似文献   

11.
To determine the effects of A3α‐peptidoglycan (A3α‐PG) extracted from Bifidobacterium sp. on the growth, immune response and disease resistance of sea cucumber Apostichopus japonicus, a 70‐day feeding trial was conducted in this study. A total of 216 sea cucumbers were fed with four practical diets prepared from a commercial feed with different contents (0, 1.5, 2.5 and 4.0 g kg?1) of A3α‐PG. The specific growth rate (SGR), total coelomocyte count (TCC), phagocytotic activity and activities of four immunological enzymes in both cell‐free coelomic fluid (extracellular, EC) and coelomocyte lysate supernatant (intracellular, IC), including acid phosphatase (ACP), alkaline phosphatase (ALP), peroxidase (POD) and superoxide dismutase (SOD), were measured at the end of the feeding trial. Finally, the animals were administered a 16‐day Vibrio splendidus challenge via intraperitoneal injection to test the potency of A3α‐PG on disease resistance. Compared with the control (0 g kg?1 A3α‐PG), a significant increase (< 0.05) in SGR was observed in the groups fed with 1.5 and 2.5 g kg?1 A3a‐PG. The TCC, ranging from 7.25 × 106 to 1.05 × 107 cells mL?1, was not significantly affected (> 0.05) by A3α‐PG,. Coelomocyte phagocytotic activities in all of the A3α‐PG‐supplemented groups were significantly activated (< 0.05), but no significant difference (> 0.05) was observed. Sea cucumbers fed with 1.5 and 2.5 g kg?1 A3α‐PG exhibited significant activation (< 0.05) of EC/IC‐ACP, EC/IC‐ALP, and EC/IC‐POD activities. A significant increase in EC‐SOD activities (< 0.05) was exhibited by all groups with A3α‐PG supplementation. The challenge test showed that animals fed with diets containing 2.5 and 4.0 g kg?1 A3α‐PG had significantly lower cumulative mortalities compared with the control 16 days after exposure. All of the results presented here show that A3α‐PG can positively enhance the growth, immune response and disease resistance of sea cucumber, suggesting that dietary supplementation of A3α‐PG has potential applications in the health management of economic species of sea cucumber.  相似文献   

12.
为考察A3α-肽聚糖(Peptidoglycan,PG)在凡纳滨对虾(Litopenaeus vannamei)的养成期对其免疫酶活性的影响,设立了连续投喂、间隔投喂和浸浴共6个实验组。连续投喂组中PG的添加量分别为0(对照)、0.01%、0.05%和0.1%;间隔投喂组中PG的添加量为0.05%;浸浴组的给予方式为50mg/ml,3h/次/15d。分别在30、60和90d时,测定对虾体内及血浆上清中的酸性磷酸酶(Acid phosphatase,ACP)和碱性磷酸酶(Alkaline phosphatase,AKP)活性,另外,在60d和90d时,测定对虾血细胞内酚氧化酶(Phenoloxidase,PO)活性。结果表明,30d时,PG浸浴组、0.05%和0.1%PG添加量组的ACP活性,各PG作用组的AKP活性均较对照组高,且0.1%PG添加量组的ACP活性及0.05%和0.1%PG添加量组的AKP活性较对照组增长显著(P<0.05);60d时,除间隔投喂组外,各组的ACP活性均较对照组高,且0.1%PG添加量组增长显著(P<0.05),而各实验组的AKP活性均较对照组高,且0.05%PG添加量组增长显著(P<0.05),除浸浴组外,各组血细胞内PO活性均有提高;90d时,浸浴组和间隔组的ACP和AKP活性均较对照组高,且间隔投喂组的AKP活性增长显著(P<0.05);间隔投喂组的血细胞内PO活性较对照组有增长。实验证明,PG能激活对虾的免疫力,并可作为免疫增强剂应用于对虾的生产。  相似文献   

13.
2005年10~11月,利用发病的大菱鲆鱼苗,用TCBS培养基进行细菌培养,细菌菌落为黄绿色,可判定其病原菌为弧菌属的一种。取优势种继续纯化培养,再用纸药片进行药敏试验。药敏试验结果表明,氯霉素、先锋霉素、头孢唑啉、庆大霉素、利福平、强力霉素、万古霉素7种抗生素对该病原菌有明显的抑制作用。  相似文献   

14.
To assess the effects of A3α‐peptidoglycan (A3α‐PG) extracted from Bifidobacterium sp. on the immune response and disease resistance of sea cucumber, different concentrations (0, 0.5, 5 and 50 mg mL?1) of A3α‐PG suspensions were used to perform hypodermic injection on Apostichopus japonicus, followed by a Vibrio splendidus challenge. Total coelomocyte count (TCC), phagocytosis activity and activities of four immunological enzymes in both cell‐free coelomic fluid (extra‐cellular, EC) and coelomocyte lysate supernatant (intracellular, IC), including acid phosphatase (ACP), alkaline phosphatase (ALP), superoxide dismutase (SOD) and peroxidase (POD), were measured at 2, 6, 14 and 24 h post injection (hpi). The TCC was not significantly affected (> 0.05) by A3α‐PG, ranging from 1.84 × 106 to 3.53 × 106 cells mL?1. The coelomocyte phagocytosis activity was significantly activated (< 0.05) in all the A3α‐PG treatments, whereas no significant difference was observed between them except 24 hpi (> 0.05). The EC‐ACP activity in the 5.0 mg mL?1 treatment increased significantly (< 0.05) at all sampling times, while the IC‐ACP activity in the 50 mg mL?1 treatment increased significantly (< 0.05) at 2 hpi. Also, the 5.0 mg mL?1 treatment had significant (< 0.05) increase in the EC‐ALP activity within 14 hpi and the EC‐POD activity at 2 hpi, respectively, while significantly (< 0.05) enhanced IC‐ALP and IC‐POD activities were observed in the 50 mg mL?1 treatment within 6 hpi and at 2 hpi, respectively. Only the 5.0 mg mL?1 treatment showed significant (< 0.05) increase in the EC‐SOD activity at 2 hpi and IC‐SOD activity within 14 hpi, respectively. The challenge test showed that the animals treated with 50 mg mL?1 of A3α‐PG had notably lower cumulative mortality after 14 days following V. splendidus exposure. All together, these results suggest that A3α‐PG could positively enhance immune response that effectively promotes the health status of A. japonicus against V. splendidus infection.  相似文献   

15.
文章通过对北方地区鲤鱼出血病病原、症状、流行情况以及影响疾病流行的主要因素进行分析,提出了鲤鱼出血病防治的主要措施。  相似文献   

16.
A3α肽聚糖对凡纳对虾幼体生长及抗病毒感染力的影响   总被引:7,自引:1,他引:6  
用含不同量的A3α肽聚糖(PG)(0.005%、0.01%、0.1%)的幼体饵料投喂凡纳对虾幼体,另在育苗水体中添加不同水平(0.005mg·mL-1、0.01mg·mL-1、0.05mg·mL-1)PG浸浴并以投喂不添加PG的幼体饵料的实验组作为对照,另设投喂活饵的实验组作参考,分别考察Z1-M1期、M1-PL1期、Z1-PL1期幼体的成活率,M1期、PL1期幼体体长,PL1期幼体体重,另外,PL1期仔虾经7d饲养后,检测体内酚氧化酶(PO)活性,并用白斑综合症病毒(WSSV)料投喂感染。结果显示:与投喂不添加PG幼体饵料组相比,在Z1-M1期,活饵组、0.01%PG添加量的幼体饵料组、0.005mg·mL-1PG的浸浴组幼体的成活率有极显著(P<0.01)提高,而在Z1-PL1、M1-PL1期,各实验组除0.05mg·mL-1浸浴组外均有极显著地(P<0.01)提高;各实验组除0.01mg·mL-1、0.05mg·mL-1PG浸浴组外,M1期幼体体长、PL1期幼体体重也有显著(P<0.01)增长,且各实验组PL1期幼体都有极显著(P<0.01)增长;各实验组仔虾PO活力均有极显著(P<0.01)提高;各实验组除0.1%PG添加量的幼体饵料组外,感染WSSV后仔虾的存活率有不同程度地提高。  相似文献   

17.
ABSTRACT

The present study was aimed to evaluate the effectiveness of administration of honey as a prebiotic in improving growth performance, immune response, and resistance of Pacific white shrimp Litopenaeus vannameito to Vibrio parahaemolyticus infection. In the present study, the bee honey added to practical diet at levels of 0.0%, 0.25%, 0.5%, 0.75%, and 1.0%. Shrimps were fed one of the tested diets in triplicates for 70 days. After the feeding trial, challenged was conducted with V. parahaemolyticus for two and five days. The growth performance and immune responses of shrimp in treatments with prebiotic honey were better than control one. Pacific white shrimp fed 0.75% honey showed highest survival after bacterial infection (73.33%), while lowest survival was found in the control treatment (43.33%). It may be concluded that the administration of honey at level of 0.75% was effective in improving the growth performance, immune response, and resistance of shrimp to V. parahaemolyticus infection.  相似文献   

18.
A 12‐week feeding trial was conducted to examine the replacement of fish meal with pet‐grade poultry by‐product meal (PBM‐PG) in the spotted rose snapper Lutjanus guttatus diet. Five experimental diets were formulated to contain graded levels of PBM‐PG at proportion of 250, 500, 75 or 900 g kg?1. The control diet contained sardine fish meal as the main protein source. Four groups of 15 randomly assigned L. guttatus juveniles were fed to satiation 3 times day?1. Except for the fish fed the PBM‐PG90 diet, the growth performance, survival and feed utilization efficiency of the experimental fish were not significantly lower than those of the control fish. The dietary level of PBM‐PG did significantly affect the haematological characteristics (< 0.05). The dietary dry matter and protein apparent digestibility coefficients (ADCs) decreased with increasing dietary PBM‐PG. High values for lipid ADCs were observed in all diets, with significant differences among the dietary treatments. The fish whole‐body protein, moisture, lipid and ash contents were not affected by the inclusion of dietary PBM. These results indicate that high‐quality terrestrial PBM can successfully replace more than half of the marine fish meal protein in the L. guttatus diet.  相似文献   

19.
黄瑞芳 《福建水产》2004,(4):29-31,28
本文通过对厦门海水养殖鱼虾病害的病原、流行情况、危害程度等的调查和研究,分析海水养殖鱼虾病害流行的主要特点以及病毒病、细菌病和寄生虫病的发病规律,从病害的检疫防疫,养殖模式,健康抗病苗种的培育,宏观调控和健康养殖,渔药的使用和管理,技术培训等方面提出海水养殖鱼虾病害控制对策。  相似文献   

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