Investigation of the use of bacteriophages a fishpathogens

As a result of the emergence of antibiotic resistance, it has become difficult and even impossible to combat previously easily-treated diseases in aquaculture. Therefore, in this thesis; in addition to bacteriophage isolation and identification for effective and natural control against fish pathogens, the use of bacteriophages which can be used as an alternative to antimicrobial chemotherapy in aquaculture has been investigated. In this study, phage isolation and phage enrichment studies were conducted against various fish pathogens from water samples taken from different sources and Aeromonas hydrophila and Yersina ruckeri, which were obtained from Kurbağalıdere/İstanbul; Yersina ruckeri, one of the water samples taken from Adana River/Mersin; phage isolation was performed against Escherichia coli O-157:H7 strain from the water sample taken from the faculty sewer system. Isolated phages were visualized by Transmission Electron Microscopy (TEM). Phage could not be isolated from water samples taken from three different commercial hatcheries against fish pathogens.