The present study was conducted to investigate the effects of the supplementation of an antibiotic growth promoter or novel feed additives with or without a xylanase-based enzyme complex to wheat-based diets on the growth performance, carcass yields and quality and intestinal characteristics (length of the total and small intestine, pH and viscosity of digesta, microflora) of Japanese quail. Eight hundred and forty day-old male quail chicks were randomly assigned to 14 groups of similar mean weight each of which included three replicates of 20 quail. The control group received a wheat-soyabean meal basal diet. In the treatment groups, the basal diet was supplemented with one of the following: an antibiotic, oregano essential oil, cinnamon essential oil, oregano essential oil plus cinnamon essential oil, a probiotic, a mannanoligosaccharide, and the same diets plus an enzyme. During the 35-d growth period there were no significant differences in body weight gain (BWG), feed intake (FI) or feed conversion ratio (FCR) of quail between dietary treatments. The use of oregano essential oil plus cinnamon essential oil or mannanoligosaccharide without the enzyme complex in the quail diets decreased plasma total cholesterol level compared to the control diet. The dietary supplementation of AGP, oregano essential oil, cinnamon essential oil, oregano essential oil plus cinnamon essential oil without the enzyme complex decreased plasma triglyceride levels compared with the control diet. When oregano essential oil, cinnamon essential oil, oregano oil plus cinnamon oil, a probiotic or a mannanoligosaccharide with an enzyme complex were used in a wheat based quail diet, the intestinal viscosity was significantly decreased compared to the control diet. Although the use of essential oils in combination with the enzyme complex, a probiotic and a mannanoligosaccharide with or without the enzyme complex in the wheat based diet significantly reduced the intestinal viscosity compared to the control diet, these treatments negatively decreased plasma total cholesterol and triglyceride.