The impact of dietary ions on rumen ion concentrations

Abstract

Dietary cation-anion difference (DCAD) evaluates the strong ion balance in dairy cattle diets. We performed two experiments to study the impacts of strong dietary ions (Na, K, and Cl) on the rumen environment. Our overall hypothesis was that dietary strong ions would influence their corresponding rumen concentrations. Our objective was to determine the impact of the dietary strong ions on the rumen environment. In the first experiment, five fistulated dairy cows consumed the following treatments: (1) a basal diet composed of corn silage and alfalfa hay and then the basal diet supplemented with (2) NaCl, (3) KCl, (4) NaHCO3, and (5) K2CO3. Rumen samples were collected 0, 1.5, 3, 4.5, 6, 9, and 12 h post-feeding to measure ion concentrations, pH, and volatile fatty acid concentrations. In the second experiment, we conducted a meta-analysis of published literature that measured rumen strong ion concentrations.