Aeromonas veronii, Associated with Skin Ulcerative Syndrome, Isolated from the Goldfish (Carassius auratus) in China

Abstract

Aeromonas infections are the most common bacterial disease in cultured fish. In April 2013, an epizootic ulcerative syndrome occurred on a goldfish farm in Xuzhou, central China. A gram-negative bacterium was isolated from the ulcerative lesions and internal organs of infected dragon-eye goldfish (Carassius auratus), tentatively named strain CAV-134. The results showed that the isolate was identified as Aeromonas veronii by physiological and biochemical characteristics, furthermore it was confirmed by 16S rRNA, gyrB, mu, asl and aha1 genes sequencing analysis. The pathogenicity of the isolate was confirmed in crucian carp and produced an LD50 of 1.99×106 CFU/ml. Antimicrobial susceptibility pattern of strain CAV-134 showed it was susceptible to most antimicrobial agents tested but resistant to ampicillin, amoxicillin, carbenicillin, vancomycin, teicoplanin, lincomycin and clindamycin. This is the report on the pathogenic A. veronii isolated from the skin ulcerative syndrome of dragon-eye goldfish.