Effect of Ethanol Infusion on Milk Fat Content and Composition and on Volatile Fatty Acids in the Rumen Liquor

Abstract

Three lactating dairy cows received a complete pelleted ration of 20% alfalfa hay and 80% concentrate, a diet which resulted in depressed milk fat percentages. Infusion of ethanol into the rumen (approximately 875 g/day) resulted in increases in the milk fat per cent, increased proportion of acetic, isovaleric, and valeric acids, and appearance of caproic acid up to approximately 7 molar %. The proportion of propionic acid was depressed. Blood ethanol increased from traces to 5 meq/liter. Concentration of ethanol in the rumen decreased with length of infusion period, suggesting an adaptation effect. © 1967, American Dairy Science Association. All rights reserved.