摘要
[Objectives]This study was conducted to find effective measures to prevent and control Pelteobagrus fulvidraco hemorrhage.[Methods]Typical disease materials were collected for bacterial isolation and culture and biological characteristics detection,and morphological characteristics were observed by pure culture method.Biochemical characteristics were identified by micro biochemical method.Molecular identification was performed by PCR amplification method.Drug resistance was detected by disk diffusion method.The agar diffusion method was used for the detection of in-vitro inhibitory effect.The immunogenicity of the isolates was detected by subcutaneous immunoassay.The virulence factor was detected by spot inoculation.The intraperitoneal injection was used for the detection of pathogenicity.[Results]The isolates were round,grayish white,and identified as Aeromonas.They fermented maltose,glucose,etc.,did not ferment lactose,and were negative for urea and H2S and positive for lysine and arginine.The target fragment appeared at 1 500,and the sequences shared the highest homology with Aeromonas.The isolates were highly susceptible to amikacin and gentamicin,and resistant to penicillin G and tetracycline.Eight lactic acid bacteria strains produced 1.1-1.9 cm of inhibition zone against the isolates.After the second vaccination,the titer reached 2^13;both hemolysin and protease were produced;and the test mice died within 24 h.[Conclusions]The isolates are Aeromonas,and have strong drug resistance,immunogenicity and pathogenicity.Inactivated emusion-oil vaccines of Aeromonas combined with the co-use of lactic acid bacteria and susceptible drugs can prevent the outbreak of diseases caused by Aeromonas.
[Objectives] This study was conducted to find effective measures to prevent and control Pelteobagrus fulvidraco hemorrhage. [Methods] Typical disease materials were collected for bacterial isolation and culture and biological characteristics detection, and morphological characteristics were observed by pure culture method. Biochemical characteristics were identified by micro biochemical method. Molecular identification was performed by PCR amplification method. Drug resistance was detected by disk diffusion method. The agar diffusion method was used for the detection of in-vitro inhibitory effect. The immunogenicity of the isolates was detected by subcutaneous immunoassay. The virulence factor was detected by spot inoculation. The intraperitoneal injection was used for the detection of pathogenicity. [Results] The isolates were round, grayish white, and identified as Aeromonas. They fermented maltose, glucose, etc., did not ferment lactose, and were negative for urea and H2S and positive for lysine and arginine. The target fragment appeared at 1500, and the sequences shared the highest homology with Aeromonas. The isolates were highly susceptible to amikacin and gentamicin, and resistant to penicillin G and tetracycline. Eight lactic acid bacteria strains produced 1.1-1.9 cm of inhibition zone against the isolates. After the second vaccination, the titer reached 213; both hemolysin and protease were produced; and the test mice died within 24 h. [Conclusions] The isolates are Aeromonas, and have strong drug resistance, immunogenicity and pathogenicity. Inactivated emusion-oil vaccines of Aeromonas combined with the co-use of lactic acid bacteria and susceptible drugs can prevent the outbreak of diseases caused by Aeromonas.
基金
Supported by Jiangxi Education Department(GJJ150416)
Jiangxi Science and Technology Department(20122BBF60082)
College Students’Innovation and Enterpreneurship Training Program of Jiangxi Province(201710410065)
