Poultry industry is currently gaining attention for the use of medicinal herbs as alternatives to antibiotics and growthpromoting agents (GPA). Among a wide variety of medicinal plants, Lamiaceae family is the most attractive herbs thatcontain essential oils with broad-spectrum of physiological effects in vivo. Mentha piperita L. (peppermint), which is anatural hybrid of Mentha aquatica L. (water mint) and Mentha spicata L. (spearmint) like other members of Lamiaceaefamily contains phytobiotics (or botanicals) which are secondary metabolites in herbs with positives effects on animalhealth and productivity (Windisch et al., 2008). These phytogenic agents may have stimulatory effects on the endogenoussecretion of the gastrointestinal tract (Lovkova et al., 2001; Jang et al., 2007; Yang et al., 2009) as well as antimicrobial and