Effects of fatty acids and acetone infusions on the ruminating behavior ofgoats

Metabolites, such as volatile fatty acids (VFA: acetic acid, propionic acid , butyric acid) and acetone produced by rumen fermentation, were intravenou sly infused into the jugular vein of goats during feeding to explore the me chanism and roles of these compounds in ruminating behavior (number of boli and ruminating time). Four female goats were confined in metabolism cages with a stanchion. The ruminating behavior, measured by the number of rumina tions, ruminating time, and number of remastications, decreased (P < 0.05) with an infusion of acetic acid and butyric acid. Propionic acid and aceton e infusion, however, increased (P < 0.05) the ruminating behavior. Acetic a cid, butyric acid, propionic acid and acetone influenced ruminating behavio r significantly, and therefore, the data suggest that rumination receptors sensitive to VFA and acetone are more likely to be in an area such as the b rain stem where they can respond to blood metabolite levels. (C) 2000 Elsev ier Science B.V. All rights reserved.