Reduction of Multidrug-Resistant Salmonella enterica Serovar Heidelberg Using a Dairy-Originated Probiotic Bacterium, Propionibacterium freudenreichii freudenreichii B3523, in Growing Turkeys

We investigated the antibacterial efficacy of a dairy-origin probiotic bacterium, Propionibacterium freudenreichii freudenreichii B3523 (PF), on a multidrug-resistant strain of Salmonella enterica serovar Heidelberg (SH) in growing turkeys. In 2 independent experiments, day-old poults (N = 24/experiment) were randomly assigned to 3 treatment groups (8 turkeys/group). The groups were: a negative control (NC; turkeys without PF supplementation or SH challenge), an SH control (SC; turkeys challenged with SH without PF supplementation), and a test group (PFS; turkeys supplemented with PF and challenged with SH) raised until 7 wk of age. Turkeys in the PFS group received PF once in 2 d at 10¹² cfu in 5 gallon drinking water from day 0 until 6 wk of age. Turkeys in SC and PFS groups were challenged with SH as crop gavage at 6 wk of age. After SH inoculation, the PFS group received PF daily for 7 d until the end of the study. The colonization of SH and PF in turkey ceca was determined 2 and 7 d post-inoculation of the pathogen. In addition, the effect of PF supplementation on the dissemination of SH to liver and spleen was determined. Results indicated that PF was recoverable at 4 to 4.5 log₁₀ cfu/g at the end of the study. Additionally, PF supplementation significantly reduced SH colonization in the PFS group by 1 to 1.3 log₁₀ cfu/g in the turkey ceca 2 and 7 d after SH inoculation (P ≤ 0.05), compared to the SC group. In addition, PF supplementation reduced dissemination of SH to liver and spleen (P ≤ 0.05), compared to the SC group. Results indicate that PF could be a potential probiotic strategy in turkeys to control SH colonization at a later stage of turkey production.