Meat chickens fed a high protein diet produce increased levels of putrefactive metabolites in the caeca such as ammonia, amines, phenols, indoles, skatole, cresol and branched chain fatty acids (reviewed by Qaisrani et al., 2015). Some of these metabolites are toxic and odorous (Mackie et al., 1998). A low protein diet formulated to provide all the required amino acids without excesses may reduce putrefaction and therefore the production of toxic and odorous metabolites in the hindgut and litter. This study was conducted to investigate the effect of a low protein diet on odorous metabolites emitted from litter.