Effect of replacing corn with whole-grain paddy rice and brown rice in broiler diets on growth performance and intestinal morphology.

The present study was conducted to investigate replacing corn with whole-grain paddy rice (WPR) and whole-grain brown rice (BR) in broiler chicken diets and its effect on growth performance and histological structures of the intestinal villi. Marshall Chunky male chicks (14 days old) were divided into five groups with four replicates of four chicks each. In the dietary treatments, corn in the basal diet was replaced with WPR and BR. The chickens received five experimental diets consisting of corn, WPR and BR in ratios of 100:0:0 (Control), 50:0:50 (50Corn + 50BR), 50:25:25 (50Corn + 25WPR + 25BR), 25:50:25 (25Corn + 50WPR + 25BR) and 0:50:50 (50WPR + 50BR) respectively. Feed and water were provided ad libitum for 35 day. No significant differences were found in feed intake, body weight gain and feed efficiency among the treatment groups. The relative weights of the gizzard in the 50Corn + 25WPR + 25BR, 25Corn + 50WPR + 25BR and 50WPR + 50BR groups were significantly higher than that of the Control and 50Corn + 50BR groups (p < 0.05). The gizzard pH of the experimental groups was lower than those of Control (p < 0.05). The ileal crypt of birds on the Control diets was deeper (p < 0.05) than those observed in the experimental birds. Moreover, the ileal villus height: crypt depth ratio increased (p < 0.05) in the 50WPR + 50BR group (p < 0.05) compared with the Control group. No specific changes were observed in the epithelial cells on the duodenal apical surface among the groups except that the villus of the 25Corn + 50WPR + 25BR group had cell clusters. The jejunal and ileal villus apical surface of the experimental groups showed similar morphology to the Control group. These findings suggest that WPR and BR can totally replace corn in broiler diets without negatively affecting growth performance.

Effects of whole-grain paddy rice replacement with or without enzyme addition on broiler performance and intestinal morphology.

To investigate the effect of replacing maize with whole-grain paddy rice (WPR) in broiler chicken diets, with or without enzyme addition, on growth performance and histological structures of the intestinal villi, 14-d-old Marshall Chunky male chicks were divided into 4 groups with 4 replicates of 4 chicks each. The experimental diets containing different concentrations of WPR were as follows: (1) 0 g/kg (Control); (2) 141.5 g/kg, grower, and 125.0 g/kg, finisher (25WPR); (3) 283.0 g/kg, grower, and 250.0 g/kg, finisher (50WPR); (4) 283.0 g/kg, grower, and 250.0 g/kg, finisher, and enzyme supplementation (50WPR + enzyme). All diets were formulated to be isocaloric and isonitrogenous and provided ad libitum for 35 d. There were no differences among the diets on the growth performance and digestive organ size. The villus height and cell mitosis number of all intestinal segments did not change in any treatment. The ileal villus area, duodenal cell area, duodenal and jejunal goblet cell number in the 50WPR group increased significantly relative to the control but not when enzyme was included. In the scanning electron microscope results, all experimental groups showed clear protuberant cells and cell clusters on the villus apical surface of the duodenum. In the jejunum, cell clusters and areas having cells with no microvilli were frequently found in both the 50WPR and 50WPR + enzyme groups. In conclusion, broilers fed on diets replacing maize with WPR showed hypertrophied villi of duodenum and ileum and epithelial cells in duodenum and jejunum, especially in the 50WPR group, without negatively affecting growth performance. These findings suggest that WPR can replace maize up to a level of 50% (283.0 g/kg, starter, and 250.0 g/kg, finisher) in broiler diets without enzyme supplementation. However, further studies are needed to improve our knowledge of the influence of WPR on higher numbers of birds.