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ARS Home » Plains Area » Lincoln, Nebraska » Agroecosystem Management Research » Research » Publications at this Location » Publication #253562

Title: Comparison of cattle fecal communities from animals fed diets containing corn and distiller's grains

Author
item Durso, Lisa
item Harhay, Gregory
item Wells, James - Jim
item Bono, James - Jim
item RIETHOVEN, JEAN-JACK - University Of Nebraska
item Shackelford, Steven
item Wheeler, Tommy
item Smith, Timothy - Tim

Submitted to: Microbial Ecology International Symposium
Publication Type: Abstract Only
Publication Acceptance Date: 5/2/2010
Publication Date: 8/22/2010
Citation: Durso, L.M., Harhay, G.P., Wells, J., Bono, J.L., Riethoven, J.M., Shackelford, S.D., Wheeler, T.L., Smith, T.P. 2010. Comparison of cattle fecal communities from animals fed diets containing corn and distiller's grains. PS.25.018, Abstract #393A. Abstract for Microbial Ecology International Symposium, Seattle, WA, Aug. 22-27, 2010. Abstract Book, Pg. 128

Interpretive Summary: Distiller’s grain is a byproduct of ethanol production, and is considered a good source of protein for cattle. However, there is concern that use of distiller’s grain may change which bacteria can grow and survive in the cattle gastrointestinal tract in a way that might give an advantage to pathogens such as E. coli O157:H7. Our goal was to explore the effects that a specific distiller’s grain product, called wet distiller’s grain with solubles (WDGS) has on the bacterial communities of beef cattle feces. There were significant differences in the kinds and amounts of bacteria found in the animals fed WDGS, compared to those on the traditional corn diet. For example, two groups, called Faecalibacterim and Prevotella, were lower in feces from the animals fed WDGS. We did not observe any difference in the number of Enterobacteriaceae – the group that includes E. coli O157:H7. Our conclusions are that feeding of WDGS results in significant changes in both the Gram-positive and Gram-negative bacterial flora. The changes in the communities are complex, and while it is possible that microbial community composition could affect survival of fecal pathogens, no differences were observed in these samples.

Technical Abstract: Background and aims: Distiller’s grain is a byproduct of ethanol production, and is considered a good source of protein for cattle. However, there is concern that use of distiller’s grain may create a gastrointestinal environment that allows the growth of fecal pathogens, and the specific changes that occur in beef cattle in response to distillers grains have not yet been well characterized. Our goal was to explore the effects that wet distiller’s grain with solubles (WDGS) has on the bacterial communities of beef cattle feces. Methods: Feces was collected from twelve steers, randomly assigned to WDGS or control diets. All animals were culture negative for E. coli O157:H7. A total of 4,537 clones were examined. Operational taxonomic units were assigned using DOTUR, and taxonomies were assigned using the Classifier tool available through RDP. Results: There were significant differences in the taxonomic distribution of genera in the animals fed WDGS, compared to those on the traditional corn diet. Richness and evenness indices were calculated. Based on taxonomy, the most striking difference was in the Faecalibacterim and Prevotella, which were underrepresented in feces from the animals fed WDGS. There were no differences observed in number of Enterobacteriaceae clones observed between the two diets. Conclusions: Feeding of WDGS results in significant changes in both the Gram-positive and Gram-negative bacterial flora. The changes in the communities are complex, and it is possible that microbial community composition could affect survival of fecal pathogens, although no clone-based differences were observed in these samples in the taxonomic groups to which E. coli O157:H7 belongs.