title: Rumen bacterial communities can be acclimated faster to high concentrate diets than currently implemented feedlot programs.
abstract: OBJECTIVE
  Recent studies have demonstrated RAMP, a complete starter feed, to have beneficial effects for animal performance. However, how RAMP may elicit such responses is unknown. To understand if RAMP adaptation results in changes in the rumen bacterial community that can potentially affect animal performance, we investigated the dynamics of rumen bacterial community composition in corn-adapted and RAMP-adapted cattle.
  
  
  RESULTS
  During gradual acclimation of the rumen bacterial communities, we compared the bacterial community dynamics in corn and RAMP-adapted using 16S rRNA gene amplicon sequencing. Significant shifts in bacterial populations across diets were identified. The shift in corn-adapted animals occurred between adaptation step3 and step4, whereas in RAMP-adapted cattle, the shift occurred between step2 and step3. As the adaptation program progressed, the abundance of OTUs associated with family Prevotellaceae and S24-7 changed in corn-adapted animals. In RAMP-adapted animals, OTUs belonging to family Ruminococcaceae and Lachnospiraceae changed in abundance.
  
  
  CONCLUSIONS
  Rumen bacteria can be acclimated faster to high concentrate diets, such as RAMP, than traditional adaptation programs and the speed of bacterial community acclimation depends on substrate composition.
  
  
  CONCLUSIONS
  These findings may have implications for beef producers to reduce feedlot costs, as less time adapting animals would result in lower feed costs. However, animal feeding behavior patterns and other factors must be considered.
authors.affiliation: School of Biological Science, University of Nebraska, Lincoln, NE, USA.
authors.forename: C L
authors.initials: CL
authors.lastname: Anderson
authors.affiliation: Department of Animal Science, University of Nebraska, Lincoln, NE, USA.
authors.forename: C J
authors.initials: CJ
authors.lastname: Schneider
authors.affiliation: Department of Animal Science, University of Nebraska, Lincoln, NE, USA.
authors.forename: G E
authors.initials: GE
authors.lastname: Erickson
authors.affiliation: Department of Animal Science, University of Nebraska, Lincoln, NE, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: MacDonald
authors.affiliation: Department of Animal Science, University of Nebraska, Lincoln, NE, USA.
authors.forename: S C
authors.initials: SC
authors.lastname: Fernando
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D002417:Cattle / Q000378:metabolism / Q000382:microbiology*; D004032:Diet / Q000662:veterinary; D012417:Rumen / Q000378:metabolism / Q000382:microbiology*
keywords: 16S rRNA; RAMP; bacteria; microbial community; rumen microbiology