title: Isolation and identification of bacteriophages infecting ayu Plecoglossus altivelis altivelis specific Flavobacterium psychrophilum.
abstract: In order to investigate methods for controlling systemic bacterial coldwater disease (CWD), bacteriophages that infect Flavobacterium psychrophilum were isolated by the enrichment method from pond water collected from Japanese ayu farms. The five phages isolated were classified as members of Myoviridae (PFpW-3, PFpC-Y), Podoviridae (PFpW-6, PFpW-7), and Siphoviridae (PFpW-8) and had highly variable patterns of infectivity for different F. psychrophilum isolates (n=128). The stability tests of the phages in different waters, pHs and temperatures were assessed, and the results indicated that none of the phages were affected by ayu farm conditions. Among the phages, PFpW-3 had high infectivity for F. psychrophilum isolated from ayu and other fish and demonstrated sufficient survivability in the stability tests. Thus, PFpW-3 and its indicator strain N2-3 were inoculated into cytophaga broth at different doses of multiplicity of infection (MOI) and proved to be efficient for the reduction of bacterial growth. This study may be the basis for a further evaluation of phage therapy in the treatment of CWD in Japanese ayu farms.
authors: Laboratory of Aquatic Animal Medicine, College of Veterinary Medicine, Seoul National University, Seoul 151-742, Republic of Korea.
authors: Ji Hyung
authors: JH
authors: Kim
authors: Dennis K
authors: DK
authors: Gomez
authors: Toshihiro
authors: T
authors: Nakai
authors: Se Chang
authors: SC
authors: Park
mesh_terms: D000818:Animals; D017756:Aquaculture; D001435:Bacteriophages / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology* / Q000648:ultrastructure; D005393:Fish Diseases / Q000382:microbiology / Q000821:virology; D045826:Flavobacteriaceae Infections / Q000382:microbiology / Q000662:veterinary* / Q000821:virology; D005417:Flavobacterium / Q000821:virology*; D006863:Hydrogen-Ion Concentration; D036441:Osmeriformes; D013045:Species Specificity; D013696:Temperature; D014871:Water Microbiology