Blood and Rumen Changes Following the Intra-Ruminal Administration of Glycogenic Materials

Abstract

Blood glucose, lactic acid, and ketones and rumen lactic, propionic, acetic and butyric acid concentrations were followed after dosage with propylene glycol, sodium propionate, sodium lactate, mixed sodium and calcium lactate, calcium lactate, and sucrose. Blood glucose responses ranked from greatest to least in the order of compounds listed. The 3 lactates disappeared from the rumen at equal rates. Absorption increased and fermentation decreased with increasing solubility. Relative absorption and fermentation were estimated using simultaneous measures of sodium lactate disappearance in vitro and in vivo. As rumen concentrations decreased percentage loss by absorption decreased, percentage loss by fermentation increased, and amount lost by fermentation remained nearly constant. Fermentation of the 3 lactates gave these rumen fatty acid increases as molar ratios: propionic, 0.86; butyric, 0.51; and acetic, 0.37. Blood glucose was increased and blood ketones were decreased as the proportion of pro-pionate increased in propionate-butyrate mixtures given intraruminally.