Abstract:A strain of bacterial pathogen was isolated from eyeballs of cultured Centropristis striata with the symptoms such as white chaotic, hyperaemia and paraplasm in the eyeballs. The strain grew quickly in the TCBS culture medium, and the colonies were protruding, yellow, and tackiness. The strain named CJG01 was Gram-negative, bacillus and monotricha. The intramuscular injection experiment revealed that CJG01 was virulent to C. striata with LD50 value of 2.67×105 CFU/ml. CJG01 could cause symptoms including larval exophthalmos, eyeball fall off, muscle ulceration, and fishbone exposure. Anatomical observation showed liver inflammation, splenic organ enlargement, kidney inflammation and yellow liquid in the intestine. The results of API 20NE rapid identification and related physiological and biochemical experiments showed that the growth temperature for CJG01 was 28℃–37℃, and the optimum temperature was 28℃. CJG01 could grow in TSB culture medium with 0–5% salinity. It was sensitive to vibrio inhibitors O/129, was oxidase and ornithine decarboxylase positive, and was V-P negative. CJG01 could assimilate mannitol, maltose and malic acid, but not glucose, arabinose, mannose, decanoic acid, acetic acid, citric acid, benzene, etc. The strain shared similarities with Vibrio harveyi in biochemical and biophysical properties. Analysis of the 16S rDNA sequence and the phylogenetic tree suggested that CJG01 was highly similar to V. harveyi. Based on the results above, CJG01 was identified as V. harveyi. The chemotherapyeutant sensitivity test showed that CJG01 was insensitive to ampicillin, cephalosporins ammonia benzyl, cephalosporins, norfloxacin, penicillin, azithromycin, polymyxin B, etc. It was moderately sensitive to cefazolin, streptomycin, erythromycin, clarithromycin, etc. Novobiocin, neomycin, cefoperazone, ceftriaxone, gentamicin, cefoperazone, kanamycin, ofloxacin, ciprofloxacin, fleroxacin, furazolidone, rifampicin, ciprofloxacin, tetracycline, chloroamphenicol and minocycline could effectively inhibit the growth of CJG01.
