Prevalence and Level of Escherichia coli O157:H7 in Feces and on Hides of Feedlot Steers Fed Diets with or without Wet Distillers Grains with Solubles

• Published in: Journal of food protection Vol. 72; no. 8; pp. 1624 - 1633
• Main Authors: Wells, J.E, Shackelford, S.D, Berry, E.D, Kalchayanand, N, Guerini, M.N, Varel, V.H, Arthur, T.M, Bosilevac, J.M, Freetly, H.C, Wheeler, T.L, Ferrell, C.L, Koohmaraie, M
• Format: Journal Article
• Language: English
• Published: United States Elsevier Limited 01.08.2009
• Subjects: Animal Feed - microbiology; Animal Nutritional Physiological Phenomena; Animals; bacterial contamination; Beef; Cattle; Cattle - microbiology; cattle feeding; Colony Count, Microbial; Diet; distillers grains; E coli; Edible Grain; Escherichia coli; Escherichia coli O157 - growth & development; Escherichia coli O157 - isolation & purification; Escherichia coli O157:H7; Ethanol; experimental diets; Feces; Feces - microbiology; feedlots; finishing; food pathogens; Food safety; Grain; Hair - microbiology; hides and skins; Hydrogen-Ion Concentration; isolation; Laboratories; Male; Pathogens; Potassium; Prevalence; Random Allocation; Seasons; shedding; Solubility; steers; Studies; Weaning; Zea mays
• ISSN: 0362-028X; 1944-9097
• DOI: 10.4315/0362-028X-72.8.1624

The objective of this study was to determine if wet distillers grains with solubles (WDGS) from corn in diets affected Escherichia coli O157:H7 in growing and finishing cattle; steers (n = 603) were randomly assigned to diets with or without WDGS. Hide and fecal samples were collected monthly (October through June) from each animal for enumeration and enrichment of E. coli O157:H7. In the growing phase (0 or 13.9% WDGS diets), fecal prevalence for E. coli O157:H7 in steers fed a diet with WDGS was twice that of the prevalence in control steers (P < 0.001). In the finishing phase (0 or 40% WDGS diets), the average prevalence in feces (P < 0.001) and on hides (P < 0.001) was higher for cattle fed WDGS. The average percentage of fecal E. coli O157:H7 enumerable samples during the finishing phase for cattle fed WDGS was 2.7% compared with 0.1% for control steers (P < 0.001). The average percentage of E. coli O157:H7 enumerable hide samples was not different between diets, but the cattle fed WDGS had higher levels (P < 0.05) of the pathogen. Animals fed WDGS had higher levels of E. coli (P < 0.001), higher pH values (P < 0.001), and lower concentrations of L-lactate (P < 0.001) in feces than those values of the control steers. These results indicate that feeding 40% WDGS could increase the level and prevalence of E. coli O157:H7 in and on feedlot cattle when E. coli O157:H7 is seasonally low.