Abstract
Seventy Hereford steers were randomly allotted according to origin to three diets containing approximately 10% roughage and one roughage-free diet. The roughage-free or all-concentrate diet produced significantly greater animal daily gains (P<.05) and required less feed per kilogram of gain. The amount of grain sorghum required per kilogram of gain was equal for all treatments. The presence of 10% cottonseed hulls, cottonwood sawdust or raw rice hulls in the diets did not alter any of the slaughter or carcass characteristics (P>05.) except number of abscessed livers. Steers with no roughage in the diet had 40% liver abscesses while those receiving 10% rice hulls had no liver abscesses. A random sampling of fluid from the rumens of these animals indicated low pH values with little difference between those not receiving roughage and those having 10% roughage in the diet. Approximately one-half of the rumen samples had no protozoa. Apparently, the presence of protozoa is not essential to either the health or performance of beef cattle on short-term finishing trials. Copyright © 1972. American Society of Animal Science . Copyright 1972 by American Society of Animal Science