Isolation and characterization of Salmonella bacteriophages from poulty and pig sewage wastes

Abstract

Bio-control strategies including bacteriophages as therapeutic agents seem to be cost effective approach to control pathogenic zoonotic infections like Salmonellosis in food animals. Salmonella specific bacteriophages were isolated, purified and characterized from different locations of sewage samples of swine and poultry. In the present study, two sewage lagoons i.e. one poultry farm sewage and one sewage waste yielded plaques of different sizes. Some of the plaques were clear while others were turbid. From these different plaques, 5 different bacteriophages were isolated and their genome was estimated to about 42 kbp in length. The bacteriophages were characterized with the help of restriction enzyme analysis and transmission electron microscopy. Bacteriophages named PSP 4, PSP 5 and PSP 7 belonged to family Siphoviridae and PSP 1 and PSP 6 were a member of family Podoviridae. Bacteriophages were found to be sensitive to high temperature and low pH. All 5 bacteriophages were subjected to host range analysis. Bacteriophages PSP 7 and PSP 4 had wide host range whereas bacteriophages PSP 1 and PSP 6 were selective in lyses of the bacterial strains. Overall, we have isolated Salmonella specific bacteriophages from the poultry and pig environment and this knowledge could be used in bio-control of Salmonella pathogen in poultry and pigs.