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. 1966 Jul;14(4):573–578. doi: 10.1128/am.14.4.573-578.1966

Effect of pH on Population and Fermentation in a Continuously Cultured Rumen Ecosystem1

L L Slyter 1,2, M P Bryant 1, M J Wolin 1
PMCID: PMC546784  PMID: 5951330

Abstract

The effect of pH on rumen fermentation and microbial population was studied in a continuously cultured rumen ecosystem. A marked decrease in the production of volatile fatty acids and methane from alfalfa hay occurred when the cultures were maintained at pH values below 6.0. The decrease in acetate and methane production was greater than that of propionate production. The culture maintained at pH 6.7 contained the types of bacteria often found in high concentration in the rumen, whereas the culture maintained at pH 5.0 had a high percentage of bacteria which could not be identified with the major rumen bacteria found in rumens of animals fed alfalfa hay. Replacement of the bicarbonate-phosphate buffer used to maintain fermentor pH at 6.7 with phosphate alone did not greatly alter the fermentation products produced from a hay-concentrate substrate.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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