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1.
陈诗宇  王利 《水产养殖》2019,(10):25-28
为了探究从鲫鱼中分离菌株SY4的基本特征,采用细菌形态学观察、理化特性、16SrDNA基因扩增及药敏试验对其进行鉴定和分析。结果表明:SY4菌株在硝酸盐还原、丙二酸盐试验中显示为阳性,葡萄糖、甘露醇、枸橼酸盐等试验为阴性,即SY4菌株理化特性与恶臭假单胞菌基本一致。得到16SrDNA序列1424bp(序列登录号为:MH142393),与恶臭假单胞菌序列相似性为99%,系统进化树中亲缘关系最近,从而判定SY4菌株为恶臭假单胞菌。药敏试验:SY4菌株对米诺环素、庆大霉素、卡那霉素和诺氟沙星等4种抗生素高度敏感;对多粘霉素B、头孢曲松等2种抗生素中度敏感;对磺胺甲基异恶唑、氨苄西林、甲氧苄定、复方新诺明、舒巴坦等5种抗生素耐药。  相似文献   

2.
恶臭假单胞菌引起的欧洲鳗鲡烂鳃病   总被引：10，自引：1，他引：10  
樊海平 《水产学报》2001,25(2):147-150
从患烂鳃病的病鳗分离到多株细菌,其中三株经人工感染证实为病原菌、经重理、生化等测试鉴定为恶臭假单胞菌。其主要特征为革兰氏阴性、具动力的短杆菌;氧化酶、过氧化氢酶、枸橼酸盐利用、精氨酸双水解酶阳性;硝酸盐还原,鸟氨酸脱羧酶、赖氨酸脱羧酶、明胶酶、尿素酶、V－P反应、吲哚反应阴性。对氟哌酸、妥布霉素、卡那霉素、庆大霉素敏感。  相似文献   

3.
网箱养殖大黄鱼假单胞菌病病原的分离与鉴定   总被引：1，自引：0，他引：1  
浙江宁波、台州等地相继发生网箱养殖大黄鱼的大量死亡,主要症状为脾脏、肾脏有许多白色结节,大小为0.1～1mm。从病鱼体内分离出致病力极强的菌株GYCWS,人工感染试验证实为大黄鱼的病原菌,其半数致死量(LD50)为8.5×104CFU/ml。对该细菌进行了形态、生理生化特性的测定,并进行了全自动微生物分析系统(ID32GN)及16S rRNA分子鉴定。经PCR扩增获得了大小约1.5Kb的16S rRNA部分基因片段,产物经回收纯化,克隆到pMD18-T载体,转化大肠杆菌TG1,对阳性克隆子进行酶切及PCR鉴定确认阳性重组质粒,将测定的序列递交NCBI进行BLAST同源序列比对,与恶臭假单胞菌的16S rRNA基因(DQ201403、AY785244)具有较高的同源性(99%),该序列在Genbank上的登录号为DQ648602。结合细菌的生理生化特性,GYCWS菌株属于恶臭假单胞菌(Pseudo monas putida)。药敏试验结果表明,病原菌GYCWS对卡那霉素、庆大霉素、丁胺卡那、氟派酸、四环素、链霉素药物敏感。  相似文献   

4.
利用平板稀释涂布法和平板划线分离纯化法,自凡纳滨对虾养殖池塘中分离得到5株细菌,经过形态观察、生理生化特性以及16S rDNA序列分析,对分离菌株进行鉴定,同时对其硝化功能和氨氮去除特性进行研究。试验结果显示,分离得到的5株细菌分别为门多萨假单胞菌、嗜胺甲基杆菌、放射根瘤菌、施氏假单胞菌和氧化微杆菌。对其净化效果进行验证可知,门多萨假单胞菌和施氏假单胞菌对氨氮的去除率超过85%,分别为88.83%和91.73%;对亚硝态氮的去除率超过90%,分别为95.08%和97.39%;对硝态氮的去除率超过90%,分别为90.49%和91.22%。以上两种菌株有较高的氨氮和亚硝态氮去除效果,具有潜在的应用价值。  相似文献   

5.
腐败假单胞菌人工感染河蟹的毒性试验及药物敏感性实验   总被引：3，自引：0，他引：3  
陈军昌  于莉 《水产科学》1999,18(2):18-20
介绍了从不同的养殖区内,采集河蟹病蟹样品。在濒死的蟹体内分离检出的菌株,经系统生化鉴定有１２株菌,被鉴定为假单胞菌属;腐败假单胞菌。为研究证明腐败假单胞菌对河蟹的致病性及其毒力的强度,用人工注射的方法进行试验观察。  相似文献   

6.
异育银鲫类志贺邻单胞菌的鉴定   总被引：3，自引：0，他引：3  
采用API 20E系列生化鉴定、生理生化特征、电镜观察和16S rDNA序列构建系统发育树分析方法,对从濒死的异育银鲫(Carassius auratus gibelio♀×Cyprinus carpio♂)肝脏中分离到的1株致病菌(革兰氏阴性杆菌,YCS07-01株)进行了鉴定。结果显示:菌株主要生化特性为氧化酶阳性,发酵葡萄糖产酸不产气,分解肌醇;不发酵蔗糖、甘露醇、鼠李糖等;β-半乳糖苷酶、精氨酸双水解酶、赖氨酸脱羧酶、鸟氨酸脱羧酶阳性。负染电镜观察,菌株为两端钝圆直杆状,无芽胞,无荚膜,有4根鞭毛,大小为0.8~1.0μm×3.0μm。在以该菌16SrDNA序列(GenBank登录号FJ375179)和GenBank数据库内同源性较高的细菌16S rDNA序列构建的系统发育树中,分离菌YCS07-01与类志贺邻单胞菌ATCC14029T(登录号X74688)的同源性为99%,并聚为一个分支。综合培养特征、形态和生理生化特性、系统发育分析等将该菌鉴定为类志贺邻单胞菌(Plesiomus shigelloides)。药敏试验结果表明菌株对羧苄青霉素和万古霉素耐药;对头孢唑啉、四环素和氨曲南中度敏感;对丁胺卡那霉素、左氟沙星、头孢他啶、复方新诺明等高度敏感。  相似文献   

7.
于翔 《河北渔业》2011,(7):1-4,45
从本院试验场患竖鳞病鲤鱼鳞囊、肝、肾中分离出病原菌3株,对其中2株进行分类鉴定,分离自病鱼鳞囊的菌株为鲶爱德华氏菌(Edzuardsiella ictaluri ),分离自病鱼肾脏的菌株为荧光假单胞菌(Pseudomonas fluorescens).药敏试验结果表明:卡那霉素、氧哌嗪青霉紊对三株菌均有较强抑制作用.  相似文献   

8.
血鹦鹉铜绿假单胞菌病原菌鉴定和药敏试验   总被引：1，自引：1，他引：0  
对从患病血鹦鹉(Cichlasoma var.)肝、眼部脓肿处分离到2株细菌,对该分离菌进行人工感染实验、鉴定和药敏实验。结果显示:通过人工感染实验证明其对血鹦鹉有较强的致病性。分离菌革兰氏阴性杆状,氧化酶阳性、接触酶阳性、甲基红阴性,能够利用枸橼酸盐、丙二酸盐,发酵葡萄糖。综合分离菌的表型特征及分子生物学结果,鉴定分离菌为假单胞菌属(Pseudomonas)的铜绿假单胞菌(Pseudomonas aeruginosa)。药敏试验结果显示头孢哌酮、头孢他啶、壮观霉素、阿米卡星、阿奇霉素、氨噻酸单胺菌素和阿洛西林抑菌效果显著。  相似文献   

9.
为研究2013年春夏之际罗源湾海区网箱养殖大黄鱼(Pseudosciaena crocea)内脏出现白点症状的病原,从具有临床症状的大黄鱼内脏中分离到优势菌,经回接感染试验证实该菌为病原菌;分析该病原菌的形态特征、理化特性、分类地位及药物敏感性等特性,结合16S r DNA序列构建的进化树与假单胞菌属恶臭群中的变形假单胞菌同源性最高,在99%以上,并通过看家基因gyr B序列分析进一步验证该菌为变形假单胞菌(Pseudomonas plecoglossicida);该菌对强力霉素、诺氟沙星、恩诺沙星3种抗生素敏感,对奥氟沙星、左氟沙星、四环素3种抗生素中度敏感。  相似文献   

10.
老化参池刺参腐皮综合征致病原的分离与鉴定   总被引：1，自引：0，他引：1  
黄华伟  陈霞  王印庚  张凤萍 《水产学报》2010,34(9):1460-1468
从患病刺参体表病灶组织分离出菌株060330B,其优势度高达90%,人工回接感染试验证实其具有较强的致病性,可导致健康刺参出现与自然患病刺参相同的症状。通过形态学观察、API半自动化鉴定和常规生理生化试验的结果表明,菌株060330B具有假单胞菌属的特征,其表型特征与恶臭假单胞菌相似。对该菌株进行16SrRNA基因序列分析和构建系统发育树,结果显示其与恶臭假单胞菌的亲缘关系最近,相似率达到99.5%。菌株060330B可鉴定为恶臭假单胞菌,并视为养殖刺参腐皮综合征的致病原之一。通过对多起不同来源患病刺参的研究表明,使用年限长、淤泥层厚呈黑色并伴有腥味的养殖池塘在该时期容易导致刺参腐皮综合征的发生。  相似文献   

11.
Anguilla luzonensis and A. huangi were each described in 2009 using eels obtained from northern Luzon Island. We examined the taxonomic status of these two groups of eels using morphological and molecular genetic characters. There were no significant differences in two vertebrae counts between eels of A. luzonensis and A. huangi. Mitochondrial 16S ribosomal RNA and cytochrome b genes sequences were obtained and compared among 28 specimens of A. luzonensis, the holotypes of A. luzonensis and A. huangi, and one specimen of the other 15 anguillid species. The specimens of A. luzonensis exhibited almost identical sequences, including the holotype, with only a few site differences, and the genetic difference between the holotypes of A. luzonensis and A. huangi was within the range of differences of specimens of A. luzonensis. The other anguillid species were genetically very different from A. luzonensis and A. huangi, although A. interioris is a closely related species. It is clear that A. luzonensis and A. huangi are the same species, and according to the principle of priority in zoological nomenclature, A. luzonensis Watanabe, Aoyama, and Tsukamoto, 2009 is the valid species name, and A. huangi Teng, Lin, and Tzeng, 2009 is a junior synonym of A. luzonensis.  相似文献   

12.
The purpose of this study was to evaluate the acute toxicity of lead for different life stages of shrimp, Litopenaeus vannamei, and to determine the effect of its sublethal concentrations on osmoregulatory capacity (OC) as well as the possible histological alteration in the gills of juvenile shrimp. The 24‐, 48‐, and 96‐h LC50 values for lead to L. vannamei increased progressively with increasing life stage, from nauplii < zoeae < mysis < postlarvae < juvenile. After 15‐d exposure to 3.25, 6.50, and 9.75 mg Pb/L, the OC values of exposed shrimp were reduced by 39, 73, and 157%, respectively compared to control animals. Compared to controls, the lead concentrations in gill tissues increased significantly by 127,500, 137,500, and 141,000% in shrimps exposed to 3.25, 6.50, and 9.75 mg Pb/L, respectively. After lead exposure, hemocytic congestion in efferent vessels and multiple hyperplasia were observed in gill filaments, resulting in narrowed hemolymphatic lacuna. The histopathological effects increased with increasing Pb concentration.  相似文献   

13.
Mulloway (Argyrosomus japonicus) occur in estuarine and coastal waters surrounding Australia, Africa, India, Pakistan, China, Korea and Japan, where they are important in fisheries. This study identified that mulloway in south-eastern Australia had similar growth rates, but matured at smaller lengths and younger ages, to those in South Africa and Western Australia. Growth of both sexes was similar to about 5 years, after which females grew faster and attained a greater maximum length than males. Female mulloway matured at 4–5 years of age with a L50 of 68 cm, whereas males matured at 2–3 years of age with a L50 of 51 cm. The commercial fishery in New South Wales was characterised by declining catches and a reduction in the proportion of mulloway of mature lengths in landings. During 2002–2005 commercial landings were dominated (83%) by fish within 15 cm of the current minimum legal total length of 45 cm and aged 2 and 3 years (>80%), even though mulloway can attain lengths of 200 cm and live >30 years. Estimates of the rates of instantaneous total mortality ranged between 0.34 and 0.45, whilst the rate of instantaneous natural mortality (M) was estimated to be approximately 0.12. Yield-per-recruit analyses indicated that mulloway in New South Wales are being growth overfished and substantial increases in yield could be achieved by increasing the length at first harvest. Values of the spawning potential ratio were below 0.2 under a range of mortality estimates, suggesting that mulloway are at risk of recruitment overfishing. These results suggest that the spawning stock of mulloway in south-eastern Australia has been depleted and that remedial management action is required to protect this iconic species.  相似文献   

14.
Mosquitofish, Gambusia sp., have been spread throughout the world to biologically control mosquitoes. However, the fish has gained a reputation as an invasive species and has been implicated in displacing native aquatic species. Gambusia affinis are native to the southeastern United States and commonly occur in commercial channel catfish, Ictalurus punctatus, production ponds. We investigated effects of mosquitofish presence on zooplankton populations, water quality, disease occurrence, and fish production in experimental ponds. There were no differences between ponds with or without mosquitofish in numbers of calanoid copepods, cyclopoid copepods, total copepods, Bosmina sp., Ceriodaphnia sp., Moina sp., Daphnia sp., or total cladocerans. There were also no differences in copepod and cladoceran sizes. Copepod nauplii were more numerous during the summer months in ponds with mosquitofish. There were no differences in water quality variables (soluble reactive phosphorus, nitrate, nitrite, ammonia, total nitrogen, total phosphorus, pH) or phytoplankton density between ponds stocked with and without mosquitofish. Catfish production and disease occurrence were also similar between ponds with and without mosquitofish. Although mosquitofish may cause problems when stocked outside their native range, there does not appear to be any adverse effects of mosquitofish presence in catfish production ponds.  相似文献   

15.
The effects of exposing the eggs of Pacific threadfin and amberjack eggs (AEs) to different concentrations of hydrogen peroxide for 5 min on hatch rate and survival were assessed in a series of experiments using a petri dish model rearing system. Despite significant inter‐batch variation in hatch rate, it was shown that eggs of both species could be safely exposed to up to 11 340 mg L−1 H2O2 for 5 min. Exposure to 34 230 mg L−1 H2O2 for 5 min was shown to be lethal to AEs at a late stage of development. In two further experiments, it was demonstrated that Pacific threadfin eggs were resistant to all tested concentrations of a range of polyvinylpyrrolidone iodine (PVP‐I) concentrations and contact times (up to 1000 mg L−1 PVP‐I for 10 min). The level of bacteria adhering to the eggs of both species was highly variable. Where eggs were heavily colonized (>104 cfu egg−1), hydrogen peroxide concentrations of at least 11 340 mg L−1, or PVP‐I concentrations higher than 500 mg L−1 for 10 min, were required for effective sterilization. In less colonized batches, rinsing in sterile seawater or exposure to lower (550 mg L−1) concentrations of H2O2 was sufficient to result in high apparent levels of surface sterility (<1 cfu egg−1).  相似文献   

16.
对驼背鲈(Chromileptes altivelis)的胚胎发育及仔、稚、幼鱼的形态特征进行了详细的观察与研究,描述了从受精卵到仔、稚、幼鱼各发育期的时间和形态特征变化。结果表明,在水温25-26℃、盐度30的海水中,受精卵历时27 h 25 min完成整个胚胎发育过程,经历从卵裂、囊胚、原肠、神经胚到肌节形成、各器官的逐渐形成、变化、完善等一系列的胚胎发育和变化过程;根据其卵黄囊消长情况、鳞片的覆盖状态、体色发生的不同变化以及第二背鳍和腹鳍的消长,将胚后发育分为仔、稚、幼鱼3个阶段。在水温22-26℃、盐度29-31、DO≥5 mg/L的条件下,2-3 d仔鱼卵黄囊消失,开口摄食;生长发育至31 d,仔鱼已变态进入稚鱼期;培育至57 d,稚鱼完成变态,成为幼鱼。第二背鳍棘和腹鳍棘的生长与收缩等石斑鱼类早期发育的共性生长特征及其体表特性体色变化特征为驼背鲈胚后发育过程中最明显的特征。  相似文献   

17.
As an intertidal species, Apostichopus japonicus is subject to diel and seasonal temperature fluctuations. Color variation is a distinct characteristic of A. japonicus, and a new color morph, purple A. japonicus, was recently found on the coast of Rushan, Weihai City. This study was conducted to compare the performance of green, white, and purple color morphs of A. japonicus at different water temperatures to help improving aquaculture technology and management. In this study, green, white, and purple color morphs of juvenile A. japonicus (1.5 ± 0.1 g) were cultured at 10, 14, 18, 22, and 26 C for 60 d, according to the suitable temperature range for sea cucumber growth. Temperature was shown to have a significant effect on growth, energy budget, and physiology of sea cucumbers (P < 0.05). Specific growth rates, feed conversion efficiencies, and the proportion of energy allocated to growth of all three color morphs were optimal at 18 C. Activities of the enzymes related with oxidative stress, immune response, and digestion were determined. Superoxide dismutase (SOD) and trypsin activities generally reached a maximum in all three color morphs at 18 C. The purple color morph of A. japonicus was higher in growth rate, food conversion efficiency, and proportion of energy allocated to growth than green and white color morphs at 18 and 22 C, consistent with its higher trypsin and SOD activity, indicating the mutual effect of growth and physiology. At 18, 22, and 26 C, the green color morph had the highest level of lysozyme activity and purple color morph had the lowest, indicating possible infection by external pathogens of green color morph, which might be caused by high temperature. These results suggested that the optimum temperature for culture of the three color morphs was approximately 18 C, the purple had a better adaption to high temperature, and the green and white color morphs may be more susceptible to thermal stress than the purple color morph.  相似文献   

18.
《水生生物资源》1999,12(4):239-246
The effect of different parameters on short-term storage capacity of turbot ova was assessed over a 45-h period after ova collection for fertilization rates and over a 9-h period after ova collection for hatching rates. Increasing the volume of ova sampling from 0.5 to 2.5 mL, as well as adding an antibiotic–antimicotic solution or oxygen did not significantly change the storage capacity of ova. Regarding the hatching rates, a higher storage ability was recorded at 8 and 13 °C, compared to 3 °C. The mean composition of the ovarian fluid was determined (n = 57 spawns). Use of a diluent mimicking the ovarian fluid significantly decreased the storage ability as assessed by the fertilization rates but did not modify the hatching rates. Diluting ova in an artificial ovarian fluid deprived of calcium significantly decreased the fertilization and hatching rates during the storage period. Furthermore, addition or not of soybean trypsin inhibitor (Sigma T 9003) to the artificial ovarian fluid deprived of calcium did not significantly change the results. Storage capacity of control batches of ova was low: at 13 °C, without any diluent and when ova were fertilized 3 h after stripping, the hatching rate was lowered to 62.4 ± 29.4 % (mean ± SD) of the initial value.  相似文献   

19.
The effects of diets containing different levels of essential oils from savory Satureja khuzestanica Jamzad and myrtle Myrtus communis L and an immunity complement were investigated on growth, survival, nutritional indices, serum biochemistry, and hematology of farmed rainbow trout, Oncorhynchus mykiss, fry (n = 4500; 5 ± 2 g). The essential oils were dosed as 300 and 500 mg/kg diet. After 60 d, the fish fed 300 mg/kg of the essential oils showed the highest counts of white blood cells (P < 0.05). The same treatment revealed the greatest levels of hematocrit, total protein, and albumin, but glucose and cholesterol values significantly decreased compared with the control (P < 0.05). Feeding fish with 300 mg/kg of the essential oils led to highest records of specific growth rate and survival rate but the lowest feed conversion ratio (FCR), and those fed with immunity complement attained the lowest values of growth parameters. The fry fed with immunity complement and 300 mg/kg of myrtle essential oil achieved the highest and lowest FCR values, respectively. The results indicate that dietary supplementation of 300 mg/kg of the above essential oils exert positive impacts on the growth performance, feeding efficiency, and hematological factors in O. mykiss.  相似文献   

20.
The objectives of this study were to evaluate the effects of varying dilutions, pH, temperature, osmolality, and cations on sperm motility parameters in waigieu seaperch, Psammoperca waigiensis. The maximum velocity of average in path (VAP), percentage of motile cells (MOT), and duration of sperm motility (DSM) were observed when semen was diluted in artificial seawater (ASW) at a ratio of 1:100 (144.9 ± 0.6 µm/sec, 95.6 ± 0.4%, and 230.3 ± 2.3 sec, respectively), at 30 C (142.0 ± 0.6 µm/sec, 93.6 ± 0.4%, and 238.3 ± 0.9 sec, respectively), and pH 8 (144.8 ± 0.6 µm/sec, 93.3 ± 0.4%, and 234.0 ± 1.5 sec, respectively). Maximum VAP, MOT, and DSM were obtained in each solution containing 0.6 M NaCl (143.8 ± 1.0 µm/sec, 91.3 ± 2.0%, and 230.6 ± 4.2 sec, respectively), 0.6 M KCl (135.1 ± 3.1 µm/sec, 91.1 ± 3.1%, and 230.3 ± 3.7sec, respectively), 0.2M CaCl2 (105.3 ± 4.7μm/sec, 47.9 ± 2.7%, and 120.7 ± 1.3 sec, respectively), 0.2 M MgCl2 (107.3 ± 3.0 m/s, 42.1 ± 3.3%, and 120.3 ± 4.8 sec, respectively), and osmolality of 400 mOsm/kg (145.1 ± 2.5 µm/sec, 93.0 ± 2.1%, and 346.5 ± 4.4s, respectively). We used these mediums as artificial insemination media for fertilizing matured eggs. The results showed that the fertilization and hatching rates in 0.6 M NaCl (75.3 ± 0.6% and 57.0 ± 2.4%, respectively), ASW (70.8 ± 1.2% and 51.2 ± 1.8%, respectively), or 400 mOsm/kg (72.9 ± 1.8% and 55.3 ± 1.6%, respectively) were higher than that in seawater (63.9 ± 1.2% and 39.2 ± 3.9%, respectively). In conclusion, using 0.6 M NaCl, ASW, or 400 mOsm/kg as an artificial insemination medium is effective for fertilizing of waigieu seaperch.  相似文献   

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