The effect of hydrated lime on Salmonella enteritidis survival in poultry litter and poult performance

Abstract

The presence of Salmonella and/or Campylobacter in poultry litter may contribute to contaminated processed carcasses. Initially in our first study, we evaluated the effect of 5, 10, or 20% added lime on in vitro survival of Salmonella enteritidis in used poultry litter during incubations of 24, 48, or 96 h. In experiment one, addition of lime at any concentration reduced Salmonella recovery from artificially-contaminated litter by more than 1.79 log 10 cfu to undetectable levels based on direct plating within 24 h. In experiment 2, litter was experimentally inoculated with 10⁸ cfu/g Salmonella enteritidis and 5g samples were pH-corrected to neutral prior to tetrathionate enrichment (24 h) and BGA plating (24 h) for detection of positive or negative samples. At 24 or 48 h, 10/10 (100%) of untreated (control) litter samples were positive for Salmonella. Addition of lime resulted in significantly reduced Salmonella recovery incidence at 24 h. These data suggest that the addition of hydrated lime can markedly reduce Salmonella recovery in a relatively short time (<24 h) period. In the second study, the effect of blending hydrated lime (0, .2, 1, or 5% wt/v) into new wood shavings prior to poult placement on poult growth and recovery of Salmonella, Campylobacter, coliforms, total aerobic cfu at 21 or 49 d was evaluated in 2 experiments. A third experiment evaluated the effect of pre-placement lime treatment of litter of one of two similar turkey brooder houses, on the same premise and under commercial contract, on these parameters at 21 or 35 days-of-age. Although pre-placement treatment of litter with lime significantly increased recovery of Salmonella from the litter during poult growth in 1 of 3 experiments, this effect was not consistent. Lime treatment did not affect coliform recovery in any experiment, but caused a very small but significant reduction in recoverable aerobic cfu in 2 experiments. Treatment of litter with one concentration of lime caused significantly increased body weights in 2 of three experiments, suggesting a beneficial effect of lime treatment of litter on turkey growth during this period.