on performance of animals and feed intake are well documented, little is known about thee ffects of glycerol on fermentation pattern and microbes in the rumen. Wangetal.(2009) reported linear increases in rumen propionate and butyrate molar proportions and a linear reduction in acetate to propionate ratio withincreasingglyceroldoses(100,200and300g/head/day)insteers’diet.Incontrast,rumenmolarproportionsforacetate, propionate and butyrate were unaffected by feeding glycerol to beef cattle at levels up to 120/kg of concentrate DM (Mach et al., 2009).