Research Notes Ability of Bacteriophages Isolated from Different Sources to Reduce

ABSTRACT Salmonella enterica serovar Enteritidis-ly-sing bacteriophages isolated from poultry or human sew-age sources were used to reduce Salmonella Enteritidis in vitro and in experimentally infected chicks. Cocktails of 4 different bacteriophages obtained from commercial broiler houses (CB4∅) and 45 bacteriophages from a mu-nicipal wastewater treatment plant (WT45∅) were evalu-ated. In experiment 1, an in vitro crop assay was con-ducted with selected bacteriophage concentrations (105 to 109 pfu/mL) to determine ability to reduce Salmonella Enteritidis in the simulated crop environment. Following 2 h at 37°C, CB4 ∅ or WT45 ∅ reduced Salmonella Enteriti-dis recovery by 1.5 or 5 log, respectively, as compared with control. However, CB4 ∅ did not affect total SE re-covery after 6 h, whereas WT45 ∅ resulted in up to a 6-log reduction of Salmonella Enteritidis. In experiment 2, day-of-hatch chicks were challenged orally with 3 × 103 cfu/chick SalmonellaEnteritidis and treated cloacally wit