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991.
2010年3月采集在湛江港爆发的利玛原甲藻赤潮海水,测定了湛江港利玛原甲藻赤潮海水对凡纳滨对虾虾苗、斑节对虾虾苗、菲律宾蛤仔、丽文蛤和乌塘鳢的毒性.结果表明,利玛原甲藻对2种虾苗有一定的毒性影响,其中对凡纳滨对虾虾苗的96 h半致死浓度为1.990×106个/L,对斑节对虾虾苗的96 h半致死浓度为1.214×106个...  相似文献   
992.
为探讨特异性卵黄抗体抗致急性肝胰腺坏死病副溶血弧菌 (Vibrio parahaemolyticus associated with acute hepatopancreatic necrosis disease, VpAHPND) 感染的效果及其机制,防控对虾急性肝胰腺坏死病 (Acute hepatopancreatic necrosis disease, AHPND),本研究以添加不同剂量VpAHPND卵黄抗体制剂 (0、0.2%和0.5%) 的饲料投喂凡纳滨对虾幼虾,测定对虾的生长率和存活率、对虾肝胰腺免疫酶活力和免疫基因相对表达水平,通过浸浴感染实验测定免疫对虾抗VpAHPND感染的能力。生长实验结果显示,免疫28 d后,免疫组与未添加卵黄抗体制剂的对照组对虾在平均生长率、特定生长率和存活率方面均无显著性差异。免疫功能实验结果显示,免疫14 d后,与对照组相比,0.2%免疫组对虾肝胰腺的酚氧化酶 (PO)、超氧化物歧化酶 (SOD)、溶菌酶 (LZM) 活力显著升高,抗菌肽 (Crustin) 基因的相对表达水平也显著升高,而β-1,3-葡聚糖结合蛋白-脂蛋白 (β-GBP-HDL) 基因的相对表达水平则显著降低。浸浴感染实验结果显示,0.2%免疫组对虾的存活率显著高于对照组;0.2% VpAHPND卵黄抗体制剂对凡纳滨对虾的相对免疫保护率为63.77%。研究表明,口服卵黄抗体不会对凡纳滨对虾的生长和存活产生不良影响,0.2%的VpAHPND卵黄抗体制剂通过提升凡纳滨对虾的PO、SOD、LZM活力和Crustin基因表达水平,增强凡纳滨对虾的免疫功能,从而提高对虾抗VpAHPND感染的能力,具有很强的应用潜力。本研究为使用特异性卵黄抗体防控AHPND提供了依据,也为其作用机制研究提供了参考。  相似文献   
993.
Penaeid shrimps are among the most studied crustaceans, mainly regarding their immune system, and several proteins involved in the defense against pathogens have been described. Haemocytes are very dynamic cells responsible of recognition, phagocytosis, degranulation and nodule formation, but still little is known about their gene expression. Using differential display, we found modification in haemocyte gene expression after inoculation with an abiotic particle (DEAE‐Sephadex) or potential pathogenic bacteria (Vibrio alginolyticus). We also noticed that some of the newly expressed genes are exclusive from a specific treatment. Here we report that haemocytes from Litopenaeus vannamei are capable of recognizing and distinguishing different foreign materials, and respond specifically to each treatment, indicating some specificity in shrimp immune response.  相似文献   
994.
采用超高效液相色谱-四级杆-飞行时间质谱(UPLC/Q-TOF MS)对恩诺沙星在凡纳滨对虾(Litopenaeus vannamei)体内和体外肝胰腺微粒体孵育下的代谢产物进行定性分析。体内试验为凡纳滨对虾口灌30 mg.kg-1恩诺沙星,24 h后采集血浆用于代谢产物分析。体外试验为在含有肝微粒体的NADPH体系中加入恩诺沙星(100μM)进行孵育,检测孵育液中的代谢产物;肝胰腺采集自未给药的凡纳滨对虾,超速离心法制备而得。凡纳滨对虾血淋巴中除以恩诺沙星原形药物为主外,还可检测到少量的N-去乙基代谢产物环丙沙星、环丙沙星哌嗪环开环代谢物及其同分异构体;而在肝胰腺微粒体体外孵育体系中除检测到原形药物外,只有少量的N-去乙基代谢物环丙沙星。无论是体内还是体外,代谢产物生成量都很少,但环丙沙星是主要代谢产物。推测恩诺沙星在凡纳滨对虾体内的代谢反应主要是脱乙基反应和加氢还原反应,而在体外肝胰腺微粒体恩诺沙星代谢的反应主要是脱乙基反应。  相似文献   
995.
This research work evaluates the impact of 1.2% pomegranate peel extract (Pp) (Punica granatum), 0.1% grapefruit seed (Gfs) (Citrus paradisi) extract, and synthetic preservative 1.25% sodium bisulfite on shelf life extension of Litopenaeus vannamei stored at 4 and 15°C. The application of isothermal titration calorimetry (ITC) for comparison of the extracts and chemical preservative on shrimp quality retention based on the overall heat production by microbial and enzymatic degradation was addressed. The occurrence of probable bioactive responsible for antimicrobial and antioxidant activity components in the extracts was examined through gas chromatography-mass spectrometry (GCMS). At 4°C, Pp-treated shrimps resulted in 6.73 logCFU/g, 6.93 logCFU/g, 5.31 mgN/100 g, and 0.58 mgMDA/kg for aerobic plate count, psychrotrophic bacterial count, trimethylamine, and thiobarbituric-acid reactive substance, respectively, on the 15th day. At 15°C, Pp-coated shrimps retained quality until day 4. Isothermal calorimetric analysis resulted in a rapid and sharp peak for fresh samples, whereas there was broad and delayed peak for shrimp treated with Pp and sodium bisulfite. These observations prove that Pp counterpart the chemical preservative and outperform Gfs on shrimp quality retention. Results also indicate that isothermal calorimetry can be a useful technique for shelf life predictions and comparative evaluation of extract impact on shrimp quality retention.  相似文献   
996.
采用假交替单胞菌(Pseudoalteromonas sp.) KL-3 2010和微小杆菌(Exiguobacterium sp.) KL-C2 2014作为益生菌,进行凡纳滨对虾(Litopenaeus vannamei)投喂实验,研究上述菌株对带毒对虾的生长与存活的影响。假交替单胞菌KL-3 2010对致急性肝胰腺坏死副溶血弧菌(Vibrio parahemolyticus) (VPAHPND 20130629002S01)有拮抗作用和胞外蛋白酶活性,微小杆菌KL-C2 2014有胞外蛋白酶活性。待试对虾经检测为白斑综合征病毒(WSSV)、致急性肝胰腺坏死病副溶血弧菌(VPAHPND)和虾肝肠胞虫(EHP)弱阳性。经过为期60 d的养殖实验,结果显示,与投喂普通颗粒饲料的对照组相比,投喂假交替单胞菌KL-3 2010的对虾存活率提高了213%±43% (P<0.01);投喂微小杆菌KL-C2 2014的对虾平均生长率提高了105.5%±28.1% (P<0.05);交替投喂2株菌的对虾存活率提高了184%±52% (P<0.05),平均生长率提高了70.6%±32.8%。肠道可培养优势菌研究表明,2株益生菌的投喂显著影响了对虾肠道优势菌群的种类。本研究为带毒虾苗的养殖提供一种有效的病害防控和促生长的手段。  相似文献   
997.
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   
998.
基于选择指数法对凡纳滨对虾(Litopenaeus vannamei)生长和高氨氮耐受性进行选择,用3种方法评估选择效果:Ⅰ)比较选择系和对照系相关性状的育种值;Ⅱ)比较选择家系和对照家系的最小二乘均值;Ⅲ)比较选择系与对照系表型值,计算相关性状的现实遗传力、遗传获得,并采用BLUP法估算相关性状的遗传力及遗传相关。结果显示,生长性状的选择反应为0.493~1.039,高氨氮耐受存活的选择反应为0.028~0.046;凡纳滨对虾生长性状的现实遗传力为0.288~0.315,遗传获得为6.45%~20.16%,高氨氮耐受成活率的现实遗传力为0.016,遗传获得为2.09%;BLUP法估算生长性状遗传力为0.216~0.284,且显著(P0.05),高氨氮耐受性遗传力为0.028±0.026,生长性状间呈高度遗传正相关为0.871~0.948,体质量与高氨氮耐受性间的正遗传相关为0.180±0.032,且显著(P0.05)。研究表明,采用选择指数法选育一代后,生长性状提高明显,高氨氮耐受性提高较小;选育群体生长性状具有较大遗传改良潜力,如何快速提高选育群体的高氨氮耐受性有待进一步研究。  相似文献   
999.
Peneid shrimp are commonly reared in clear‐water aquaria or tanks for short‐term studies of 4–6 weeks during controlled experiments, such as nutrition studies to estimate dietary nutrient requirements. Recently, in line with the genetic program at Centre Océanologique du Pacifique (COP), experimental clear‐water facilities were tested for the first time over a longer rearing period. Environmental conditions used to maintain animal growth in clear‐water system using a well‐balanced diet were defined. After 100 days, shrimp growth rates tended to decrease and only by adjusting the diet could shrimp complete their life cycle and reach maturation size of around 40 g. This paper presents information on stocking density, diet quality and husbandry linked to reproduction that must be considered to successfully rear animals from PL's to breeder size in clear water. By following these protocols a minimum amount of breeders can be used to meet production goals. Moreover, by isolating a small group of individuals, genetic diversity can be preserved, thereby allowing specific crosses for selective breeding purposes. Length of trials, amount of feed, composition of feed, growth performances and maturation success are reported and should encourage further studies to optimize rearing conditions in clear‐water rearing.  相似文献   
1000.
为研究我国凡纳滨对虾(Litopenaeus vannamei)商业苗种的遗传多样性特征,于河北、山东、广东、海南等地采集了6个有代表性的凡纳滨对虾品牌苗种,分别命名为黄骅R、东营M、广州P、广州Z、海南S和海南Z,以8个微卫星标记检测其遗传多样性。结果显示,6个品牌的凡纳滨对虾在8个位点呈现不同程度的多态性,其平均等位基因数(Na)、期望杂合度(He)、观测杂合度(Ho)和多态信息含量(PIC)分别为4.5~9.5、0.516~0.733、0.346~0.550和0.472~0.700,各品牌遗传多样性丰富程度从高到低分别为黄骅R>广州Z>广州P>海南Z>东营M>海南S。哈迪–温伯格平衡(HWE)检验显示,4.17% (2/48)的检测结果表现为显著的偏离(0.01相似文献   
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