Reduction of Shiga-Toxin Producing Escherichia coli (STEC) and Salmonella in Cattle Manure using Lactobacillus L28 as an Environment Mitigation Treatment in the Feedlot
MetadataShow full item record
One of the agricultural industry’s leading issues for livestock is food safety. Fecal samples were collected from cattle fed three different rations: 1) monensin and tylosin with no probiotic (BASE), 2) monensin with a probiotic (L28) (MONPRO), and 3) no probiotics, tylosin or monensin (CONTROL). Fecal samples were inoculated with a cocktail mixture of three Shiga-Toxin producing E. coli (STEC) strains or Salmonella strains to an initial concentration of 2.5-3.5 log10 cfu/g. Lactobacillus salivarius L28, was used at three concentrations (106, 107, and 108 log10 cfu/ml) to determine dose-response. Samples were collected at 1, 6, 12, and 24 hr after inoculation and incubation at 37°C. STEC were enumerated on MacConkey agar with a thin-layer overlay of Tryptic Soy Agar. Pathogenic Salmonella were enumerated on Xylose Lactose Tergitol™ 4 agar with a thin-layer overlay of Tryptic Soy Agar. The results have shown an inhibition of growth of STEC and Salmonella in all three cattle fed diets. There was no significant difference between the dose response concentration (L28) by time. The objective of this research was to determine the effect of Lactobacillus L28 on the inhibition of Shiga-Toxin Producing E. coli (STECs) and Salmonella in cattle manure collected from three different sets of cattle fed three different diets using a dose-response approach to determine the potential for use as an environmental mitigation treatment and as an intervention. We hypothesized that the application of a treatment with L28 would result in inhibition of the pathogen (STEC or Salmonella) in the manure for L28 concentration level as a dose response of 10^7 and 10^8.