Eve Quiroz, Jare Recalde, Marbel Torres Arias, Rachid Seqqat, Carlos Vinueza and Ligia Ayala
The genus Salmonella, as many others bacteria, has been frequently reported as resistant to commonly used antibiotics in poultry, therefore, the current spread of antibiotic resistance genes in bacteria, raises doubts on the effectiveness of antibiotics in the future. One possible alternative to antibiotics is the use of bacteriophages as antimicrobial agents to control antibiotic resistant pathogenic bacteria. The main goal of this project was to isolate and use bacteriophages as a new, safe, and effective biocontrol method for treating infectious diseases caused by Salmonella entero-pathogena. Four lytic bacteriophages cocktails (PSEA-2, SSEA, PSIA-2, SSIA) were isolated from wastewater of poultry processing industries, to control Salmonella enterica subsp entérica serovar Enteritidis (SE), and Salmonella entérica subsp enterica serovar Infantis (SI), under laboratory conditions. We found the cocktails PSEA-2 and PSIA-2 specific for SE and SI while cocktails SSEA and SSIA also caused lysis in Pseudomona. The observations in the Transmission Electron Microscope (TEM) revealed the presence of tailed phages of the Siphovididae and Myoviridae families; and a polyhedral phage. We have isolated specific phages and tested in vitro their effectiveness at controlling Salmonella. Further studies are needed in order to assess the phage effectiveness in vivo.