Abstract
The data are presented from a replicated feeding trial designed to determine the influence of different sources of nitrogen, fed at a constant level, upon the nitrogen balances and numbers and types of ruminal microorganisms in growing Iambs. Six Merino Iambs were fed a basal ration of oaten chaff and wheaten grain supplemented with six sources of nitrogen: linseed meal, subterranean clover seed, whole powdered egg, casein, urea, and urea plus methionine.