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对虾白斑病围栏封闭预防技术 总被引:2,自引:0,他引:2
“对虾白斑病的围栏封闭预防技术”是一项针对沿海低位池塘、以切断传染病源为主旨、以设置防蟹围栏为特色的对虾白斑病综合预防技术。其主要措施为:首先在贮水(兼水处理)池和养殖池周围设置防蟹围栏,将该等池塘封闭起来,使杂蟹不会从陆地侵入池内;然后通过60目滤网进水,并用敌百虫或敌杀死处理上述两种池塘,杀灭以蟹类为主的一切甲壳动物;解毒后,放养经检测不带白斑症病毒的虾苗;采取封闭式养殖,养殖期中只向养殖池加水以补充渗漏和蒸发的水损失;加水时,先将海水在贮水池中用药物处理,杀灭其中的传染该病的媒介生物(主要是桡足类),药物解毒后再注入养殖池。此外,作为辅助措施,在养殖期中从多方面尽量保证虾池中有一个良好的生态环境。该技术已经过预备研究、实验研究和扩大试验等阶段,均证明效果良好。已扩大试验了近33.33hm^2(其中实际养虾池约17.33hm^2),成功率达96%左右。 相似文献
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单克隆抗体酶联免疫技术检测对虾皮下及造血组织坏死病的病原及其传播途径 总被引:22,自引:5,他引:22
用单克隆抗体ELISA技术对1994年5月~7月自山东和辽宁采集的虾池和海区材料,包括对虾、浮游生物、小型甲壳类生物、鱼类、底泥及饲料等共192个样品进行了对虾暴发性流行病病原HHNBV的检测。结果表明,对虾中的HHNBV阳性与虾池发病情况基本相符,用单抗ELISA方法可提前20~40d对虾池的发病可能性作出预报;桡足类浮游生物的带毒率高于对虾,且其阳性的出现早于对虾,沿岸海区的桡足类浮游生物有较高的阳性率,它可能是对虾暴发性流行病的主要病原携带者;部分地区的卤虫也带有HHNBV,同时还从糠虾等小型甲壳类生物中检出了病原。 相似文献
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利用沿海池塘养殖海蜇,已成为继海水池塘养殖南美白对虾、梭子蟹后的又一大亮点。笔者经过二三年的反复试验养殖,发现五种外界因素对海蜇生长至关重要。1饵料生物的数量海蜇的生长离不开饵料,因海蜇只摄食活的浮游生物,如:桡足类、枝角类、小型甲壳类及部分有机碎屑,尤其喜爱轮虫和卤虫。在平时的养殖中,人们主要是通过换水和人工施肥来维持水中饵料生物量,以促进海蜇的快速生长。养殖前期,池塘内浮游生物充足,基础饵料较好,稚蜇摄食量低,海蜇的饵料不成问题。但当伞径长到10cm左右,因其昼夜摄食,摄食量大,池塘内浮游生物的数量已不能满足生长需要。此时,一方面在养成池塘内一角专门用筛绢网围成桡足类培养池,对其施肥,人工管理,及时把桡足类捕捞到养成池,这时海蜇又开始生长;另一方面收购或采捕天然轮虫、卤虫或枝角类,进行活体投喂,效果也非常明显,海蜇迅速恢复生长。可见池塘内饵料生物的存池量,对海蜇的快速生长起到了关键性作用。2水质管理养蜇先养水,水体要保持“肥、活、嫩、爽”,就必须经常进排水,为海蜇的生长提供足够的饵料生物。一方面,通过进排水,可以补充水体中的浮游生物量,保证有充足的饵料生物;另一方面,经常性的缓进缓排,不仅可以保证水体肥活... 相似文献
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用DNA斑点杂交法检测对虾及其饵料和环境生物携带白斑综合症病毒状况的调查 总被引:13,自引:3,他引:13
于1996-1998年采用DNA斑点杂交法,完成了共计836份养殖对虾,213份对虾饵料和环境生物样品的检测。结果显示,对虾在每年的4-10月都可检测出白斑综合症病毒(WSSV),6月出现最高峰,阳性检出率达到42.6%;其次,为7月和5月,分别达31.6%和24.5%。在对虾不同生长阶段(包括亲虾、各期幼体、仔虾、幼虾及成虾)均可检出WSSV,其中以仔虾的带毒率最高,达36.4%,其次为糠虾幼体,达34.6%。体长范围1.1-2.0cm的仔虾阳性率最高,其次体长为5.1-6.0cm的幼虾样品。检测的中国对虾样品(625份)带毒率为16.8%,日本对虾样品(211份)带毒率为45.0%。对虾主要饵料及环境生物类群包括鱼类、虾类、蟹类、桡足类、端足类、沙蚕、卤虫均可检出WSSV,其中小型虾类、端足类、桡足类、蟹类样品的WSSV检出率均高于20%。 相似文献
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自 1992~ 1993年暴发养殖对虾病毒性疾病以来 ,对虾养殖一直受到白斑病的困扰。尽管近年来对虾养殖正在缓慢回升 ,但如何推迟或避免白斑病的发生 ,从而使对虾能够达到较大规格上市 ,获得较好的经济效益 ,是对虾养殖业亟待解决的问题。对虾白斑病发病季节长 ,每年 5~ 10月间均有发生 ,而以 5~ 6月和 9~ 10月发病较集中 (此时对虾体长约 5~ 6 cm) ,死亡率高。一般来说 ,放养密度越高、对虾规格越大 ,发病越严重。其严重程度有时从发现个别对虾死亡到全塘对虾死亡仅 3~ 7天。对于病毒性的虾病目前尚缺乏针对性的药物 ,因此 ,重点是提高对… 相似文献
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为了解桡足类在池塘育苗模式下的动态变化规律,研究了在斜带石斑鱼池塘育苗生态系统中浮游桡足类的种群增长情况、生产率和呼吸率。试验结果:2口试验池塘中的桡足类主要有7种,其中矮拟哲水蚤(Paracalanus nanus)、小拟哲水蚤(P.parvus)这两种小型桡足类为优势种;育苗期间,桡足类的生物量呈现出前10天逐渐升高、第10 d达到最大值、之后逐渐降低的特点;育苗池中桡足类的平均世代时间为42.312 h,平均生产率为4. 560 mg/(L·d),平均日P/B系数为0. 723 5;育苗全过程桡足类的呼吸率为0.074 4 mg/(L·d),单只桡足类的平均呼吸率为4.055×10^-5mg/(L·d)。结果表明,到育苗后期,自然增长的桡足类远不能满足鱼苗摄食的需要,需每天向池塘增加投放桡足类及轮虫等。 相似文献
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对虾WSSV病是亚洲对虾养殖业中的一个棘手问题。本研究采用Kimura引物 ,用PCR技术对不同生长期的中国对虾 (Penaeuschinensis)进行了WSSV的检测 ,同时也检测了对虾发病时养殖池中多见的野生厚蟹 (Helicesp .)和矛尾刺虎鱼 (Acanthogobiushasta)。检测结果表明 :分别在检测的 5尾亲虾中的 1尾 ,6尾仔虾中的 1尾 ,5尾稚虾中的 3尾及所检测的 5尾病虾和 2只厚蟹中获得到 982bp的PCR扩增产物 ,说明为WSSV感染阳性。在检测的 2尾矛尾刺虎鱼中均未获得PCR扩增产物 ,说明为WSSV感染阴性。在亲虾、虾苗以及虾池内的野生厚蟹中检测到WSSV感染的阳性结果表明 :WSSV感染的亲虾有可能是病毒的储主 ,WSSV感染的野生厚蟹有可能是病毒中间宿主或病毒的携带者 ,它们在对虾WSSV病的感染、传播中起了重要的作用 相似文献
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以超低温保存的感染了白斑综合征病毒(WSSV)的中国对虾制备的病毒粗提液为毒种,注射感染凡纳对虾并收集濒死虾,DNA斑点杂交检测每尾凡纳对虾WSSV感染状况。取DNA斑点杂交呈强阳性的30尾对虾,平均分为3组,病毒粗提液也平均分成3组,3组材料分别通过^60Co辐照,辐照时间分别为12、24和36h,辐照剂量为0.8KGy/h。辐照后的材料经PCR检测证实^60Co辐照不能完全破坏WSSV的DNA组成。以辐照后的感染白斑综合征病毒的对虾个体和白斑综合征病毒粗提液为感染毒种,人工感染健康凡纳对虾,验证^60Co辐照对病毒感染力的破坏作用,证实^60Co辐照可显著降低WSSV病毒粗提液的感染力,^60Co辐照可适当降低WSSV感染对虾的感染力。 相似文献
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S. Thamizhvanan S. Sivakumar S. Santhosh Kumar D. Vinoth Kumar S. Suryakodi K. Balaji T. Rajkumar S. Vimal S. Abdul Majeed G. Taju A. S. Sahul Hameed 《Journal of fish diseases》2019,42(3):447-454
White leg shrimp, Penaeus vannamei, were collected on a monthly basis from grow‐out ponds located at Tamil Nadu and Andhra Pradesh states along the east coast of India for screening of viral and other pathogens. Totally 240 shrimp samples randomly collected from 92 farms were screened for white spot syndrome virus (WSSV), infectious hypodermal and haematopoietic necrosis virus (IHHNV), infectious myonecrosis virus (IMNV) and Enterocytozoon hepatopenaei (EHP). The number of shrimp collected from shrimp farms ranged from 6 to 20 based on the body weight of the shrimp. All the shrimp collected from one farm were pooled together for screening for pathogens by PCR assay. Among the samples screened, 28 samples were WSSV‐positive, one positive for IHHNV and 30 samples positive for EHP. Among the positive samples, four samples were found to be positive for both WSSV and EHP, which indicated that the shrimp had multiple infections with WSSV and EHP. This is the first report on the occurrence of multiple infections caused by WSSV and EHP. Multiplex PCR (m‐PCR) protocol was standardized to detect both pathogens simultaneously in single reaction instead of carrying out separate PCR for both pathogens. Using m‐PCR assay, naturally infected shrimp samples collected from field showed two prominent bands of 615 and 510 bp for WSSV and EHP, respectively. 相似文献
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海捕中国对虾杆状病毒的检测 总被引:3,自引:0,他引:3
以海捕中国对虾为材料,利用多聚酶链反应(PCR)技术和核酸探针技术,对从中国对虾杆状病毒核酸随机文库中筛选的4个片段(大小分别为800,1100,1500,2500bp)用地高辛标记作为探针,进行斑点杂交,检测对虾杆状病毒。结果表明海捕中国对虾的鳃、中肠、肝胰腺、卵巢等组织检测为阳性,肌肉组织为阴性。实验表明中国对虾村状病毒存在垂直传播的可能性。 相似文献
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白斑症病毒在日本对虾体内的感染增殖 总被引:9,自引:0,他引:9
用投喂患白斑症病毒病的虾组织人工感染日本对虾稚虾,每日取样,整虾冰冻切片,单克隆抗体的荧光抗体方法,原位观察病毒在虾体内的感染增殖,结果表明:感染后三天内,在感染虾的各组织器官内均未观察到明显的病毒感染的阳性细胞,每四天首先在鳃丝腔内的小量血细胞观察到病毒感染;第五天除血细胞外同时在血窦,鳃上皮组织,皮下组织内观察到,第六天进而在心脏,胃上皮组织内观察到:第七天进一步又在淋巴器官,中肠内观察到,八 相似文献
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White spot syndrome (WSS) is considered as a great threat to commercial farming of the tiger shrimp (Penaeus monodon). The causal agent of WSS is a DNA virus called white spot syndrome virus (WSSV). The prevalence of this dreadful virus infection
has been studied in five randomly selected hatcheries located in the Cox’s Bazar district of Bangladesh. Both one-step and
nested polymerase chain reaction (PCR) involving two pairs of primers, namely, 146F1/146R1 and 146F2/146R2, amplifying the
1447 bp and 941 bp fragments, respectively, were conducted to detect the WSSV. Out of 60 randomly collected shrimps, 12 (20%)
were found to be positive by one-step PCR, while 18 (30%) were found to be positive by nested PCR. The nested PCR was found
to be much more sensitive than the one-step PCR. The shrimp specimens showing clinical signs of WSS were positive for WSSV
by both one-step and nested PCR. Some of the apparently healthy samples were also found to be positive for WSSV by nested
PCR. Among the two primer-pairs, the inner pair amplifying the 941 bp fragment was more sensitive than the outer primer pair
amplifying the 1447 bp fragment when used in one-step PCR. 相似文献
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中国对虾杆状病毒垂直传播途径的研究对切断病毒的传播途径,培育健康的对虾种质资源,具有重要的理论和实践意义。本文利用电镜技术,对中国对虾亲虾的卵巢,卵细胞和无节幼体,溲状幼体,糠虾,仔虾,幼成虾进行病毒检测,结果发现卵巢和卵细胞中有似病毒粒子,无节幼体,糠虾,仔虾,幼成虾有杆状病毒感染,并初步探讨了中国对虾杆状病毒垂直传播的可能性。 相似文献
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Luz Isela Peinado-Guevara 《Aquaculture (Amsterdam, Netherlands)》2006,251(1):33-45
WSSV has caused great losses to the global shrimp industry in recent years. This virus can infect shrimps asymptomatically. However, once the clinical signs are developed, mortalities can reach 100% in 3-10 days. PCR has been extensively used to detect WSSV in a specific and sensitive manner. Nested PCR is even more sensitive than single-step PCR and had been used for the detection of WSSV in asymptomatic populations. In this work, a detailed monitoring of WSSV by nested PCR in shrimp commercial ponds in Guasave County, State of Sinaloa, Mexico, is presented. Five ponds from two different farms were monitored for growth and presence of WSSV. At the beginning of the culture, ponds from both farms showed no or very slight WSSV presence. A 3-day period of rain occurred at both farms 10 and 14 weeks of culture for farms 1 and 2, respectively. At this time, WSSV was widely distributed in the shrimp populations of farm 1 according to nested-PCR data, although no visual symptoms were observed. In ponds of farm 2, WSSV was present at low level. However, the number of PCR-positive groups was drastically increased in both farms by nested and single-step PCR. Abrupt fluctuations in temperature and salinity were documented in farm 2 after the rain, which may have contributed to the increasing of viral load in the pond's shrimp populations. Twelve days after the rain period, estimated mortalities of 80% occurred in farm 1. Nevertheless, the study ponds at farm 2 culture continued normally for three more weeks and were harvested successfully (52% and 67% of survival for ponds 1 and 2, respectively). The removal of 40% and 50% of shrimp population 2-4 days after the raining period may have contributed to the thriving of the cultures. Analyses of the presence of WSSV in individuals of both sexes indicated that there is no preference for this virus to infect male or female shrimp. Also, no differences in weight were found between WSSV infected and non-infected individual shrimps, as well as nested-PCR positive against single-step PCR positive organisms. Nested PCR is more useful to monitor shrimp cultures than single-step PCR since it allows knowing how widely distributed the virus is in asymptomatically populations. 相似文献