Publisher : The Korean Society of Fisheries and Aquatic Science
DOI : 10.5657/KFAS.2015.0725
Title & Authors
Edwardsiella ictaluri Infection in Cultured Yellow Catfish Pelteobagrus fulvidraco Fingerlings in Korea Kim, Jin Do; Park, Sung Woo;
We observed yellow catfish Pelteobagrus fulvidraco fingerlings cultured in land ponds in Korea swimming in a corkscrew spiral pattern while hanging head-up and tail-down at the water surface, before eventually dying. Externally, these fish displayed “hole in the head” disease, pale gills, and hemorrhages in the base of the pectoral and caudal fins; internally they had liver hemorrhages and kidney discoloration. The bacterium Edwardsiella ictaluri (YCK-01 and YCL-01) was identified in the kidneys and livers of diseased fish via phenotypic characteristics and PCR analysis using the ictaluri-specific primers IVS (an intervening sequence) and IRS (the inter-ribosomal spacer). Infectivity challenges by intraperitoneal and immersion routes showed that a representative bacterial strain (YCK) exhibited strong virulence to yellow catfish, with an LD50 of 3.2×104 CFU/fish and 2.5×106 CFU/mL, respectively. This is the first report of E. ictaluri infection in yellow catfish from Korea.