ABSTRACT
Using disinfectants in poultry houses is a common practice to ban the zoonotic pathogens like Salmonella. A major concern in using disinfectants is the emergence of bacteria strains that resist some disinfectants. This phenomenon is manifested in the resistance of some Salmonella serotypes against quaternary ammonium compounds. Such resistance is attributed to qacEΔ1 gene which may be possessed by some Salmonella serotypes. This work aimed to evaluate the resistance of Salmonella serotypes (S. Typhimurium, S. Infantis and S. Entiridis) against different disinfectants (benzalkonium chloride, iodine, gluteraldehyde and hydrogen peroxide). The effect of the disinfectants were evaluated by treatment of the bacteria with different concentrations (1:100, 200 and 400) at different temperatures and periods. Bacterial count was performed before and after the treatment. PCR for presence of qacEΔ1 gene was also performed before and after the treatment. The biocidal effect of the disinfectants found to be dependent on concentration, temperature and treatment period in addition to the type of the disinfectant. Hydrogen peroxide proved to be the most active agent followed by gluteradehyde, iodine and benzalkonium chloride. A link between the resistance against benzalkonium chloride and the existence of qacEΔ1 gene was proven in S. Typhimurium, whether treated or not treated with benzalkonium chloride.
Keywords:
Disinfectants; PCR; Poultry; Resistance; Salmonella
