黄沙鳖幼鳖类志贺邻单胞菌病病原菌分离鉴定及药敏试验

Isolation and identification of Plesimonas shigelloides pathogenic bacteria from young Truogx sinensis and its drug sensitivity test

【目的】对广西武鸣县某养鳖场患病黄沙鳖幼鳖进行病原菌的分离鉴定及药敏试验,旨在找出黄沙鳖幼鳖的发病原因,为生产实践中有效防治该病提供参考。【方法】用常规方法从患病濒死黄沙鳖幼鳖的心脏、肝脏及病灶等处分离病原菌,通过人工感染试验确定分离菌株的致病性,用API20NE生化鉴定系统对病原菌进行鉴定,药敏试验采用K-B纸片扩散法,并根据药敏试验结果选用高度敏感药物对该病进行防治。【结果】分离获得的两株优势菌株(WMB-A和WMB-B)对健康黄沙鳖均有很强的致病性,都是导致黄沙鳖幼鳖发病死亡的病原菌,经API20NE生化鉴定系统鉴定均为类志贺邻单胞菌(Plesiomonasshigelloides)。两株分离菌株的药敏试验结果虽不尽相同,但均对菌必治、舒普深、氟哌酸、多粘菌素B和环丙沙星高度敏感,对青霉素G、氨苄青霉素、苯唑青霉素、特治星、先锋霉素VI、复方新诺明、万古霉素、阿莫西林、头孢克肟、头孢噻吩、阿洛西林、头孢氨苄、新生霉素、头孢克洛和磺胺-6-甲氧嘧啶(钠)不敏感。选用菌必治拌料(50mg/kg·d)连续投喂6d,治疗效果良好。【结论】广西武鸣县某养殖场黄沙鳖幼鳖发病死亡是由类志贺邻单胞菌感染引起,可选用菌必治、舒普深、氟哌酸、多粘菌素B和环丙沙星等5种药物进行防治。

[Objective]Pathogenic bacteria in young diseased Truogx sinensis which was kept in a fish farm in Wuming County, Guangxi, were isolated and identified. Then its drug sensitivity test was conducted to seek out the aetiological agent for effective treatment and prevention. [Method]Pathogenic bacteria were separated from the heart, liver and focus in dying young Truogx sinensis using routine method. Pathogenicity of isolates was determined by artificial infection experiment. Pathogenic bacteria were identified using API 20NE. K-B was applied to test drug sensitivity. Highly-sensitive drugs were chosen for treatment based on the test results. [ResuhlTwo dominant strains （WMB-AST ＆ WMB-B） possessed strong pathogenicity against healthy Truogx sinensis. In other words, they were pathogenic bacteria causing Truogx sinensis to death, and after API 20NE test, they were identified as Plesimonas shigeHoides. The results of these two strains were not identical. However, both of them were highly sensitive to Ceftriaxone sodium, sulperazone, norfloxacin, polymyxin B and Ciprofloxacin, and not sensitive to penicillin G, ampicillin, oxacillin, tazocin, cephalosporin VI, selectrin, vancomycin, amoxicillin, cefixime, cefalotin, novobiocin, cefaclor and sulfanilamide-6-sulfamethoxydiazine （Na）. Six-day-use of ceftriaxone sodium（50 mg/kg, d） had positive treatment results. [Conclusion]The death of young Truogx sinensis was caused by Plesimonas shigelloides infection. Five kinds of drugs （Ceftriaxone sodium, sulperazone, norfloxacin, polymyxin B, Ciprofloxacin） could be prescribed for prevention and treatment.