Comparison of ryegrass and red clover on the fermentation pattern, microbial community and efficiency of diet utilisation in the rumen simulation technique (Rusitec)

A Belanche, MRF Lee, JM Moorby, CJ Newbold

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

An in vitro experiment was designed to investigate the effects of incubating two forages with a different energy/nitrogen (N) ratio [perennial ryegrass (GR) vs red clover (RC)] on the efficiency of N utilisation by rumen microbes. Second-cut forages were incubated in artificial rumen fermenters (n = 8). Ryegrass represented a supply of quickly available N and energy for the rumen microorganism which led to a rapid fermentation and bacterial growth 2–4 h after feeding. Ryegrass also promoted greater numbers of anaerobic fungi, methanogens and cellulolytic bacteria, which tended to increase neutral detergent fibre disappearance, gas production, volatile fatty acid and methane production than observed using RC diets. On the contrary, RC provided slowly degradable N and energy, which led to a relatively slow bacterial growth (4–8 h after feeding). In terms of diet utilisation, RC diets promoted a higher N outflow (mainly as undegraded-N) and efficiency of microbial protein synthesis per organic matter disappeared. Even so, microbial protein yield was similar on both diets indicating a better N capture by microorganisms fed GR than in those fed RC diets. The use of 15N-labelled forages demonstrated that this high ammonia incorporation by bacteria-fed GR occurred mainly during the early fermentation coinciding with the highest bacterial growth. In conclusion, this experiment demonstrated that the use of isotopic labelling combined with molecular techniques provided an insight into forage utilisation by the rumen microbes; GR diets led to a better efficiency of N utilisation compared with RC; moreover the lower N outflow on GR diets may be partially compensated for a higher proportion of microbial protein leaving the system and the greater volatile fatty acid production. These findings seem to indicate that RC grazing may increase the N pollution compared with GR without substantial improvements on the rumen function, however this must be confirmed in vivo.
Original languageEnglish
Pages (from-to)1052-1064
Number of pages13
JournalAnimal Production Science
Volume53
Issue number10
Early online date9 Apr 2013
DOIs
Publication statusPrint publication - 2013
Externally publishedYes

Fingerprint

Trifolium
Lolium
Rumen
Trifolium pratense
Fermentation
microbial communities
rumen
fermentation
Diet
microbial proteins
diet
forage
microbial growth
Volatile Fatty Acids
volatile fatty acids
microorganisms
methodology
energy
Growth
Bacteria

Keywords

  • Lolium perenne
  • Red clover
  • Rumen N metabolism
  • Rusitec
  • Ryegrass
  • Trifolium pratense

Cite this

@article{a061c9636ef744338eda99d534a1a025,
title = "Comparison of ryegrass and red clover on the fermentation pattern, microbial community and efficiency of diet utilisation in the rumen simulation technique (Rusitec)",
abstract = "An in vitro experiment was designed to investigate the effects of incubating two forages with a different energy/nitrogen (N) ratio [perennial ryegrass (GR) vs red clover (RC)] on the efficiency of N utilisation by rumen microbes. Second-cut forages were incubated in artificial rumen fermenters (n = 8). Ryegrass represented a supply of quickly available N and energy for the rumen microorganism which led to a rapid fermentation and bacterial growth 2–4 h after feeding. Ryegrass also promoted greater numbers of anaerobic fungi, methanogens and cellulolytic bacteria, which tended to increase neutral detergent fibre disappearance, gas production, volatile fatty acid and methane production than observed using RC diets. On the contrary, RC provided slowly degradable N and energy, which led to a relatively slow bacterial growth (4–8 h after feeding). In terms of diet utilisation, RC diets promoted a higher N outflow (mainly as undegraded-N) and efficiency of microbial protein synthesis per organic matter disappeared. Even so, microbial protein yield was similar on both diets indicating a better N capture by microorganisms fed GR than in those fed RC diets. The use of 15N-labelled forages demonstrated that this high ammonia incorporation by bacteria-fed GR occurred mainly during the early fermentation coinciding with the highest bacterial growth. In conclusion, this experiment demonstrated that the use of isotopic labelling combined with molecular techniques provided an insight into forage utilisation by the rumen microbes; GR diets led to a better efficiency of N utilisation compared with RC; moreover the lower N outflow on GR diets may be partially compensated for a higher proportion of microbial protein leaving the system and the greater volatile fatty acid production. These findings seem to indicate that RC grazing may increase the N pollution compared with GR without substantial improvements on the rumen function, however this must be confirmed in vivo.",
keywords = "Lolium perenne, Red clover, Rumen N metabolism, Rusitec, Ryegrass, Trifolium pratense",
author = "A Belanche and MRF Lee and JM Moorby and CJ Newbold",
year = "2013",
doi = "10.1071/AN12183",
language = "English",
volume = "53",
pages = "1052--1064",
journal = "Animal Production Science",
issn = "1836-0939",
publisher = "CSIRO",
number = "10",

}

TY - JOUR

T1 - Comparison of ryegrass and red clover on the fermentation pattern, microbial community and efficiency of diet utilisation in the rumen simulation technique (Rusitec)

AU - Belanche, A

AU - Lee, MRF

AU - Moorby, JM

AU - Newbold, CJ

PY - 2013

Y1 - 2013

N2 - An in vitro experiment was designed to investigate the effects of incubating two forages with a different energy/nitrogen (N) ratio [perennial ryegrass (GR) vs red clover (RC)] on the efficiency of N utilisation by rumen microbes. Second-cut forages were incubated in artificial rumen fermenters (n = 8). Ryegrass represented a supply of quickly available N and energy for the rumen microorganism which led to a rapid fermentation and bacterial growth 2–4 h after feeding. Ryegrass also promoted greater numbers of anaerobic fungi, methanogens and cellulolytic bacteria, which tended to increase neutral detergent fibre disappearance, gas production, volatile fatty acid and methane production than observed using RC diets. On the contrary, RC provided slowly degradable N and energy, which led to a relatively slow bacterial growth (4–8 h after feeding). In terms of diet utilisation, RC diets promoted a higher N outflow (mainly as undegraded-N) and efficiency of microbial protein synthesis per organic matter disappeared. Even so, microbial protein yield was similar on both diets indicating a better N capture by microorganisms fed GR than in those fed RC diets. The use of 15N-labelled forages demonstrated that this high ammonia incorporation by bacteria-fed GR occurred mainly during the early fermentation coinciding with the highest bacterial growth. In conclusion, this experiment demonstrated that the use of isotopic labelling combined with molecular techniques provided an insight into forage utilisation by the rumen microbes; GR diets led to a better efficiency of N utilisation compared with RC; moreover the lower N outflow on GR diets may be partially compensated for a higher proportion of microbial protein leaving the system and the greater volatile fatty acid production. These findings seem to indicate that RC grazing may increase the N pollution compared with GR without substantial improvements on the rumen function, however this must be confirmed in vivo.

AB - An in vitro experiment was designed to investigate the effects of incubating two forages with a different energy/nitrogen (N) ratio [perennial ryegrass (GR) vs red clover (RC)] on the efficiency of N utilisation by rumen microbes. Second-cut forages were incubated in artificial rumen fermenters (n = 8). Ryegrass represented a supply of quickly available N and energy for the rumen microorganism which led to a rapid fermentation and bacterial growth 2–4 h after feeding. Ryegrass also promoted greater numbers of anaerobic fungi, methanogens and cellulolytic bacteria, which tended to increase neutral detergent fibre disappearance, gas production, volatile fatty acid and methane production than observed using RC diets. On the contrary, RC provided slowly degradable N and energy, which led to a relatively slow bacterial growth (4–8 h after feeding). In terms of diet utilisation, RC diets promoted a higher N outflow (mainly as undegraded-N) and efficiency of microbial protein synthesis per organic matter disappeared. Even so, microbial protein yield was similar on both diets indicating a better N capture by microorganisms fed GR than in those fed RC diets. The use of 15N-labelled forages demonstrated that this high ammonia incorporation by bacteria-fed GR occurred mainly during the early fermentation coinciding with the highest bacterial growth. In conclusion, this experiment demonstrated that the use of isotopic labelling combined with molecular techniques provided an insight into forage utilisation by the rumen microbes; GR diets led to a better efficiency of N utilisation compared with RC; moreover the lower N outflow on GR diets may be partially compensated for a higher proportion of microbial protein leaving the system and the greater volatile fatty acid production. These findings seem to indicate that RC grazing may increase the N pollution compared with GR without substantial improvements on the rumen function, however this must be confirmed in vivo.

KW - Lolium perenne

KW - Red clover

KW - Rumen N metabolism

KW - Rusitec

KW - Ryegrass

KW - Trifolium pratense

U2 - 10.1071/AN12183

DO - 10.1071/AN12183

M3 - Article

VL - 53

SP - 1052

EP - 1064

JO - Animal Production Science

JF - Animal Production Science

SN - 1836-0939

IS - 10

ER -