Effect of Ethanol on Rumen Fermentation

Abstract

Ethanol (800 ml., 47.5%) was administered via rumen fistula during the once-daily feeding of: (1) 14 lb. timothy hay plus 4 lb. of equal parts of ground corn and ground corncobs or (2) Ration 1 with 3% urea replacing corn or (3) 20 lb. alfalfa hay, to twin 1,100-lb. cows. Each ration was fed with and without ethanol to each cow for 14-day periods. Four per cent of ground ration was added to cheese cloth-strained rumen fluid and incubated for 3 hr. in vitro. Ethanol was not fermented in vitro but disappeared from the rumen with a half-time of 2 hr. Blood contained 75 mg.% ethanol 2 to 4 hr. after administration. Ethanol depressed rumen fill, gas production in vitro, and the utilization of radioactive sulfate for synthesis of amino acids and glutathione, but had little effect on the volatile fatty acid concentration in the rumen. Digestibility of crude protein and organic matter was slightly reduced by feeding ethanol with grain rations (1) and (2) to four dry nonfistulated cows. © 1959, American Dairy Science Association. All rights reserved.