Methanogens in digestive tract of ruminants

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Methanogens are a group of microorganisms that produce methane as a byproduct of their metabolism. They play an important role in the digestive system of ruminants. The digestive tract of ruminants contains four major parts: rumen, reticulum, omasum and abomasum. The food with saliva first passes to the rumen for breaking into smaller particles and then moves to the reticulum, where the food is broken into further smaller particles. Any indigestible particles are sent back to the rumen for rechewing. The majority of anaerobic microbes assisting the cellulose breakdown occupy the rumen and initiate the fermentation process. The animal absorbs the fatty acids, vitamins and nutrient content on passing the partially digested food from the rumen to the omasum. This decreases the pH level and initiates the release of enzymes for further breakdown of the food which later passes to the abomasum to absorb remaining nutrients before excretion. This process takes about 9–12 hours.

Some of the microbes in the ruminant digestive system are:

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References

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  2. ↑ Cotta, M. A.; Hespell, R. B. (1986). "Proteolytic activity of the ruminal bacterium Butyrivibrio fibrisolvens". Applied and Environmental Microbiology. 52 (1): 51–8. PMC   203391 . PMID   3524460.
  3. ↑ Stackebrandt, Erko; Hippe, Hans (1986). "Transfer of Bacteroides amylophilus to a new Genus ruminobacter gen. nov., nom. Rev. As Ruminobacter amylophilus comb. Nov". Systematic and Applied Microbiology. 8 (3): 204–7. doi:10.1016/S0723-2020(86)80078-9.
  4. ↑ Avgustin, G; Wright, F; Flint, H. J. (1994). "Genetic diversity and phylogenetic relationships among strains of Prevotella (Bacteroides) ruminicola from the rumen". International Journal of Systematic Bacteriology. 44 (2): 246–55. doi: 10.1099/00207713-44-2-246 . PMID   7910475.
  5. ↑ M. P. Bryant; et al. (1958), "Bacteroides ruminicola N. Sp. and Succinimonas amylolytica the New Genus and Species: Species of Succinic Acid-Producing Anaerobic Bacteria of the Bovine Rumen", Journal of Bacteriology, 76 (1): 15–23, PMC   290147 , PMID   13563384
  6. ↑ Nisbet, D. J.; Martin, S. A. (1990). "Effect of Dicarboxylic Acids and Aspergillus oryzae Fermentation Extract on Lactate Uptake by the Ruminal Bacterium Selenomonas ruminantium". Applied and Environmental Microbiology. 56 (11): 3515–8. PMC   185007 . PMID   16348354.
  7. ↑ D. Dušková and M. Marounek (2001), "Fermentation of pectin and glucose, and activity of pectin-degrading enzymes in the rumen bacterium Lachnospira multiparus", Letters in Applied Microbiology, 33 (2): 159–163, doi:10.1046/j.1472-765x.2001.00970.x
  8. ↑ O'Herrin, S. M.; Kenealy, W. R. (1993). "Glucose and carbon dioxide metabolism by Succinivibrio dextrinosolvens". Applied and Environmental Microbiology. 59 (3): 748–55. PMC   202185 . PMID   8481001.
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