Abstract
Terramycin stimulated growth when added to a milk replacement diet. Rumen samples were obtained at ages 6, 12, and 16 wks. and checked for levels of thiamine and riboflavin. Terramycin supplementation had no apparent effect on levels of these vits. in the rumen contents. Rumen samples also were introduced into an artificial rumen for the purpose of determining the in-vitro cellulose digestive power of the rumen organisms. Terramycin in the feed or admn. by capsule significantly lowered the breakdown of cellulose as measured by the artificial rumen.