CAJ | 학술논문

2013年5—8月对三北地区主要冷水鱼养殖的虹鳟、大西洋鲑、银鲑、西伯利亚鲟等发病鱼进行病原菌的分离鉴定及药敏试验，以期为冷水鱼细菌性疾病的防控提供参考。流行病学调查结果表明不同地区发病鱼表现出不同的临床症状，西北地区青海的虹鳟主要为烂鳃、出血等；东北地区辽宁的银鲑为体色发黑、内脏有出血点等；东北地区黑龙江的大西洋鲑主要表现为肠炎、烂鳃等；华北地区的北京西伯利亚鲟表现为体表严重出血、吻端周围红肿等。无菌条件下从患病鱼内部器官取样划线培养细菌，并进行氧化酶反应、革兰染色、API 20生化鉴定、16S rRNA保守序列分子鉴定等研究方法。结果表明从患病的辽宁银鲑中分离到12株杀鲑气单胞菌、1株不动杆菌；从牡丹江大西洋鲑中分离14株杀鲑气单胞菌、6株温和气单胞菌、2株嗜水气单胞菌、6株不动杆菌、2株黄杆菌；青海虹鳟鱼中分离到9株温和气单胞菌、6株维氏气单胞菌、6株不动杆菌、2株黄杆菌、2株鲁氏耶尔森菌；从北京房山西伯利亚鲟鱼中分离到3株海豚链球菌、3株不动杆菌、10株停乳链球菌、2株维氏气单胞菌、2株嗜水气单胞菌、1株黄杆菌。药敏试验结果表明：在89株菌中有92．13％和96．63％的菌株对氨苄西林和阿莫西林具有很强的耐药性，有100％、93．26％、91．10％、92．13％、91．01％和94．38％的菌株分别对左氧氟沙星、氧氟沙星、庆大霉素、卡那霉素、环丙沙星和恩诺沙星敏感，其中对左氧氟沙星无耐药菌株；另外，不同地区相同病原菌对抗生素的敏感程度也有一定程度的差异。
2013년5—8월대삼북지구주요랭수어양식적홍준、대서양해、은해、서백리아심등발병어진행병원균적분리감정급약민시험，이기위랭수어세균성질병적방공제공삼고。류행병학조사결과표명불동지구발병어표현출불동적림상증상，서북지구청해적홍준주요위란새、출혈등；동북지구료녕적은해위체색발흑、내장유출혈점등；동북지구흑룡강적대서양해주요표현위장염、란새등；화북지구적북경서백리아심표현위체표엄중출혈、문단주위홍종등。무균조건하종환병어내부기관취양화선배양세균，병진행양화매반응、혁란염색、API 20생화감정、16S rRNA보수서렬분자감정등연구방법。결과표명종환병적료녕은해중분리도12주살해기단포균、1주불동간균；종모단강대서양해중분리14주살해기단포균、6주온화기단포균、2주기수기단포균、6주불동간균、2주황간균；청해홍준어중분리도9주온화기단포균、6주유씨기단포균、6주불동간균、2주황간균、2주로씨야이삼균；종북경방산서백리아심어중분리도3주해돈련구균、3주불동간균、10주정유련구균、2주유씨기단포균、2주기수기단포균、1주황간균。약민시험결과표명：재89주균중유92．13％화96．63％적균주대안변서림화아막서림구유흔강적내약성，유100％、93．26％、91．10％、92．13％、91．01％화94．38％적균주분별대좌양불사성、양불사성、경대매소、잡나매소、배병사성화은낙사성민감，기중대좌양불사성무내약균주；령외，불동지구상동병원균대항생소적민감정도야유일정정도적차이。
Due to its delicious taste,rich nutrition and high content of protein,cold?water fish has been cultured worldwide nowadays. However,bacterial diseases frequently occurred during the aquaculture of cold?water fish because of high density,bad water quality,poor quality of feed and so on,which could also indirectly affect people’ s health. At present,control of bacterial diseases still depends on antibiotics in China,but the abuse of antibiotics will cause drug residues and multi?drug resistance of bacteria,so it is necessary for us to study the characteristics of pathogenic bacteria existing in cold?water fish aquaculture. In this study,common pathogenic bacteria were isolated and identified from farm?raised rainbow trout,Atlantic salmon,silver salmon and Siberia sturgeon in the three north areas of China during the period from May to August in 2013.Based on the epidemiology investigation,different kinds of diseases occurred in fish with different clinical signs:gill?rot, haemorrhage in diseased rainbow trout from Qinghai Province;exophthalmosis,darkening in color,saprolegnia?sis and bleeding spots in internal organs in diseased silver salmon from Liaoning Province;enteritis,gill?rot in Atlantic salmon from Heilongjiang Province and haemorrhage on body surface,mouth irritation,etc. in Siberia sturgeon from Beijing City.Samples were collected and streaked on the plate,and isolated bacteria were inocu?lated under aseptic conditions. The results indicated that 12 strains of Aeromonas salmonicida and 1 strain of Acinetobacter were isolated from diseased silver salmon cultured in Liaoning;14 strains of Aeromonas salmonici?da,6 strains of Aeromonas sobria,2 strains of Aeromonas hydrophila,6 strains of Acinetobacter,2 strains of Fla?vobacterium were isolated from diseased Atlantic salmon cultured in Mudanjiang;9 strains of Aeromonas sobria, 6 strains of Aeromonas veronii,6 strains of Acinetobacter,2 strains of Flavobacterium,2 strains of Yersinia ruckeri were isolated from diseased rainbow trout cultured in Qinghai;3 strains of Streptococcus iniae,3 strains of Acine?tobacter 10 strains of Streptococcus dysgalactiae,2 strains of Aeromonas veronii,2 strains of Aeromonas hydrophi?la,1 strain of Flavobacterium were isolated from diseased Siberia sturgeon cultured in Fangshan,Beijing. Anti?microbial susceptibility test showed that 92.13% and 96.63% of isolated strains were highly resistant to ampi?cillin and amoxicillin respectively,100%,93. 26%,91. 10%,92. 13%,94. 38% of the strains were sensitive to levofloxacin,ofloxacin,gentamicin,kanamycin,ciprofloxacin and enrofloxcin respectively and no strains exhibi?ted resistance to levofloxacin.In addition,there were some differences in antimicrobial susceptibility in the same pathogenic bacteria isolated from different regions in a certain degree. In short,this study describes the isola?tion,characterization and antimicrobial susceptibility of pathogenic bacteria isolated from farm-raised cold-wa?ter fishes.The results discovered here may provide some theoretical basis for the prevention and control of bac?terial diseases which occur in cold-water fishes.