Characterization and experimental infection of Flexibacter maritimus (Wakabayashi et al. 1986) in hatcheries of post-larvae of Litopenaeus vannamei Boone, 1931

Brazilian Journal of Biology

Jlp. Mouriño²  L. Vinatea²  C. Buglione-neto²  Ct. Ramirez¹  Fn. Vieira²  F. Pedrotti²  Ml. Martins¹  Rb. Derner²  Ma. Aguilar²  E. Beltrame² 

[1] ,Universidade Federal de Santa Catarina Departamento de Aqüicultura Laboratório de camarões marinhosFlorianópolis SC ,Brazil

关键词: Litopenaeus vannamei;    hatchery;    Flexibacter maritimus;    experimental infection;    Litopenaeus vannamei;    pós-larvas;    Flexibacter maritimus;    infecção experimental;   

DOI  :  10.1590/S1519-69842008000100025

来源: SciELO

【 摘 要 】

A preliminary study to characterize filamentous bacteria, whose presence is related to high mortality of Litopenaeus vannamei larvae cultured in Santa Catarina State, Brazil, is reported. The extract of infected larvae was diluted in different concentrations, cultured in marine agar (DifcoTM, Marine Agar 2216) and incubated at 30 °C for 48 hours. The biochemical characterization included hydrolytic reactions of starch, gelatin and tyrosine, growth in TCBS agar, growth in 0 and 37‰ salinity, pigment production in tyrosine agar, production of H2S, nitrate reduction, congo red reaction, oxidase and catalase. The isolated bacteria belong to the species Flexibacter maritimus, Gram-negative bacilli of 0.4-0.5 µm width and 15 µm length. Experiments were carried out on pathogenicity of F. maritimus in post-larvae of L. vannamei. Survival and symptoms in L. vannamei post-larvae 24 hours after inoculation with F. maritimus and its growth in marine agar were evaluated. Mortality was detected around 92,5% as well as symptoms like melanized lesions in several parts of body, discolouration of gills, bad formation of appendages and of the last abdominal segment, low motility and feeding reduction. The experimental infection results suggested that isolated bacteria of the genus Flexibacter are pathogenic to the shrimp Litopenaeus vannamei post-larvae.

【 授权许可】

CC BY   
 All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License