关键词: 大黄鱼（Larimichthys crocea）, Vibrio ponticus, 分离鉴定, 药敏分析, Larimichthys crocea, Vibrio ponticus, isolation & identification, antibiotic sensitivity analysis

Abstract: In 2013, the large yellow croaker (Larimichthys crocea) cultured in net cage at Ningde was diseased.The sick fish appeared symptoms of gill filaments ulcers and gill rakers bare. One dominant bacterial strain, named as Lc-2013-G1, was isolated from the gill of sick L. crocea. The strain Lc-2013-G1 was confirmed to be a bacterial pathogen of L. crocea by arificial infection. Physiological and biochemical characteristics showed that the pathogen Lc - 2013 - G1 formed a smooth, moist, marginally yellow colony on the TCBS medium, which was Gram - negative and arc - shaped rod. The strain Lc - 2013 - G1 had motility and grew in a medium containing 6% sodium chloride. The indicators of V-P, arabinose, sputum matrix andcitrate were negative to Lc-2013-G1, while the indicators of galactose, catalase and amylase were positive to Lc-2013-G1. The pathogen Lc-2013-G1 was determined to be Vibrio ponticus based on morphological and physiological detection, biochemical tests and 16S rRNA gene analysis. Antibiotic sensitivity analysis indicated that the pathogen Lc-2013-G1 was sensitive to Ampicillin, Polymyxin B, Sulimethoxazole, Norfloxacin, Piperacillin, Gentamycin, Cefoperazone, Ofloxacin, and so on. The results provided a reference for the prevention and treatment of large yellow croaker disease caused by Vibrios.