Adenosine Triphosphate in the Bovine Rumen During Maximum Nutrient Supply and Starvation

Abstract

The concentration of adenosine triphosphate (ATP) in rumen fluid from heifers fed high levels of nutrients continuously and after 12–24 h starvation has been determined in order to examine the influence of different physiological conditions. The conventional parameters for characterizing the rumen fermentation have been applied to control the effect of a different nutrient supply. The mean concentration of ATP, determined by the luciferin‐luciferase assay, was 55.3 mg ATP/l rumen fluid in a heifer fed continuously, twice as much as found in a starved heifer. The mean ratio of biomass/ATP changed from 683 at the high level of energy intake to 1208 in the period of starvation. Consequently, the concentration of ATP in the rumen micro‐organisms is markedly influenced by nutritional conditions. Finally, the applicability of ATP determinations in rumen microbiology is discussed.