Usual pH of rumen fluid

Range 5.8 - 6.8 unitless
Organism Mammals
Reference Bergman EN, Energy contributions of volatile fatty acids from the gastrointestinal tract in various species. Physiol Rev. 1990 Apr70(2):567-90. abstract or p.571 left column bottom paragraphPubMed ID2181501
Comments "Results typical of total and individual rumen VFA concentrations as affected by diet are shown in Table 1 [BNID 111254]. Acetate predominates under most conditions, but substantial amounts of propionate and butyrate are always present (12, 102, 131, 296). Valeric and higher acids usually constitute ~5% of the total. Diets rich in starch, such as cereal grains, favor propionate production, and in general, those diets that are rapidly fermented give rise to less acetate. The pH of rumen fluid usually is in the range of 5.8-6.8, but a rapid fermentation can lower the pH to <5.0. This seems to encourage growth of organisms that especially produce both propionate and lactate (30,98)."
Entered by Uri M
ID 111255