The role of ciliate protozoa in the rumen

Charles J Newbold, Gabriel de la Fuente, Alejandro Belanche, Eva Ramos-Morales, Neil R McEwan

Research output: Contribution to journalReview article

109 Citations (Scopus)
3 Downloads (Pure)

Abstract

First described in 1843, Rumen protozoa with their striking appearance were assumed to be important for the welfare of their host. However, despite contributing up to 50% of the bio-mass in the rumen, the role of protozoa in rumen microbial ecosystem remains unclear. Phylogenetic analysis of 18S rDNA libraries generated from the rumen of cattle, sheep, and goats has revealed an unexpected diversity of ciliated protozoa although variation in gene copy number between species makes it difficult to obtain absolute quantification. Despite repeated attempts it has proven impossible to maintain rumen protozoa in axenic culture. Thus it has been difficult to establish conclusively a role of ciliate protozoa in rumen fiber degradation. The development of techniques to clone and express ciliate genes in λ phage, together with bioinformatic indices to confirm the ciliate origin of the genes has allowed the isolation and characterization of fibrolytic genes from rumen protozoa. Elimination of the ciliate protozoa increases microbial protein supply by up to 30% and reduces methane production by up to 11%. Our recent findings suggest that holotrich protozoa play a disproportionate role in supporting methanogenesis whilst the small Entodinium are responsible for much of the bacterial protein turnover. As yet no method to control protozoa in the rumen that is safe and practically applicable has been developed, however a range of plant extract capable of controlling if not completely eliminating rumen protozoa have been described.

Original languageEnglish
Article number1313
JournalFrontiers in Microbiology
Volume6
DOIs
Publication statusPrint publication - 2015
Externally publishedYes

Fingerprint

Rumen
Axenic Culture
Genes
Bacterial Proteins
Gene Dosage
Methane
Plant Extracts
Ribosomal DNA
Computational Biology
Goats
Bacteriophages
Ecosystem
Sheep
Clone Cells

Cite this

Newbold, Charles J ; de la Fuente, Gabriel ; Belanche, Alejandro ; Ramos-Morales, Eva ; McEwan, Neil R. / The role of ciliate protozoa in the rumen. In: Frontiers in Microbiology. 2015 ; Vol. 6.
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abstract = "First described in 1843, Rumen protozoa with their striking appearance were assumed to be important for the welfare of their host. However, despite contributing up to 50{\%} of the bio-mass in the rumen, the role of protozoa in rumen microbial ecosystem remains unclear. Phylogenetic analysis of 18S rDNA libraries generated from the rumen of cattle, sheep, and goats has revealed an unexpected diversity of ciliated protozoa although variation in gene copy number between species makes it difficult to obtain absolute quantification. Despite repeated attempts it has proven impossible to maintain rumen protozoa in axenic culture. Thus it has been difficult to establish conclusively a role of ciliate protozoa in rumen fiber degradation. The development of techniques to clone and express ciliate genes in λ phage, together with bioinformatic indices to confirm the ciliate origin of the genes has allowed the isolation and characterization of fibrolytic genes from rumen protozoa. Elimination of the ciliate protozoa increases microbial protein supply by up to 30{\%} and reduces methane production by up to 11{\%}. Our recent findings suggest that holotrich protozoa play a disproportionate role in supporting methanogenesis whilst the small Entodinium are responsible for much of the bacterial protein turnover. As yet no method to control protozoa in the rumen that is safe and practically applicable has been developed, however a range of plant extract capable of controlling if not completely eliminating rumen protozoa have been described.",
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The role of ciliate protozoa in the rumen. / Newbold, Charles J; de la Fuente, Gabriel; Belanche, Alejandro; Ramos-Morales, Eva; McEwan, Neil R.

In: Frontiers in Microbiology, Vol. 6, 1313, 2015.

Research output: Contribution to journalReview article

TY - JOUR

T1 - The role of ciliate protozoa in the rumen

AU - Newbold, Charles J

AU - de la Fuente, Gabriel

AU - Belanche, Alejandro

AU - Ramos-Morales, Eva

AU - McEwan, Neil R

PY - 2015

Y1 - 2015

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