Open AccessChanges in Rumen Microbial Community Composition during Adaption to an In Vitro System and the Impact of Different Forages
Author(s) -
Melanie B. Lengowski,
Karin Helga Renate Zuber,
Maren Witzig,
Jens Möhring,
J. Boguhn,
M. Rodehutscord
Publication year - 2016
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0150115
Subject(s) - fibrobacter succinogenes , biology , rumen , silage , ruminococcus , food science , microbial population biology , bacteria , forage , zoology , microbiology and biotechnology , fermentation , agronomy , genetics
This study examined ruminal microbial community composition alterations during initial adaption to and following incubation in a rumen simulation system (Rusitec) using grass or corn silage as substrates. Samples were collected from fermenter liquids at 0, 2, 4, 12, 24, and 48 h and from feed residues at 0, 24, and 48 h after initiation of incubation (period 1) and on day 13 (period 2). Microbial DNA was extracted and real-time qPCR was used to quantify differences in the abundance of protozoa, methanogens, total bacteria, Fibrobacter succinogenes , Ruminococcus albus , Ruminobacter amylophilus , Prevotella bryantii , Selenomonas ruminantium , and Clostridium aminophilum . We found that forage source and sampling time significantly influenced the ruminal microbial community. The gene copy numbers of most microbial species (except C . aminophilum ) decreased in period 1; however, adaption continued through period 2 for several species. The addition of fresh substrate in period 2 led to increasing copy numbers of all microbial species during the first 2–4 h in the fermenter liquid except protozoa, which showed a postprandial decrease. Corn silage enhanced the growth of R . amylophilus and F . succinogenes , and grass silage enhanced R . albus , P . bryantii , and C . aminophilum . No effect of forage source was detected on total bacteria, protozoa, S . ruminantium , or methanogens or on total gas production, although grass silage enhanced methane production. This study showed that the Rusitec provides a stable system after an adaption phase that should last longer than 48 h, and that the forage source influenced several microbial species.