Khonyoung, D., Yamauchi, K., Buwjoom, T., Maneewan, B. and Thongwittaya, N. 2012. Effects of dietary dried fermented ginger on growth performance, carcass quality, and intestinal histology of heat- stressed broilers. Can. J. Anim. Sci. 92: 307-317. To investigate the effects of a dried fermented ginger product (DFG) on growth performance, carcass quality, and intestinal histology of heat-stressed broiler, at 7 d of age, 200 male broilers were divided into 0% (control), 0.25% (0.25 S F), 0.5% (0.5 S F) and 1% (1 S F) dietary DFG groups fed from 7 to 49 d of age (starter finisher groups, S F). Another group of chicks was fed the basal diet until 21 d of age. At 22 d of age, 150 birds from this group showing almost similar body weight were divided into 0.25% (0.25 F), 0.5% (0.5 F) and 1% (1 F) dietary DFG groups fed from 22 to 49 d of age (finisher groups, F); the control group was common for the S F and F groups. The average temperature was around 31°C (23.2-38.6°C) throughout the trial. Compared with the control, the experimental DFG groups were not different in feed intake, body weight gain, feed efficiency and carcass quality. However, abdominal fat of the 1 S F, 0.5 F, and 1 F groups decreased (P<0.05). Cell mitosis numbers in the duodenum tended to increase in the 1 S F group (P<0.1). Epithelial cells on the jejunal villus apical surface of the control were mainly flat, and desquamations were observed. Desquamation was reduced with increasing DFG, and in the 1% DFG groups, many protuberant cells and cell clusters were present. The present results suggest that under high ambient temperature 1% dietary DFG from 7 to 49 d of age can decrease abdominal fat, and that jejunal villus apex was desquamated with heat stress, but desquamations were reduced with increasing DFG, and disappeared in 1% DFG groups.