Microbiology of the Rumen
The rumen, or more appropriately the reticulo-rumen, is a large chamber (50–100 l capacity in adult cattle) in which the ingested feed is first subjected to microbial digestion. The rumen is an ideal microbial habitat because the conditions that exist are conducive for the survival and growth of microorganisms. The temperature remains relatively constant (36–40°). Water the animal drinks and the only exocrine secretion that rumen receives, saliva, provide a moist environment required for microbial growth. Ingested food provides the energy and other nutrients needed for microbial growth and activity. Normal reticulo-ruminal motility (peristalsis and antiperistalsis) helps mix the contents, which brings microbes into contact with fresh substrate. The end products of fermentation are removed by absorption (acids) into the blood or eructation (gases). Absorption coupled with the buffering effect provided by salivary secretions help regulate ruminal pH.
KeywordsConjugate Linoleic Acid Cellulolytic Bacterium Ciliated Protozoan Anaerobic Fungus Feed Particle
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