No abstract

The present study was conducted to investigate the effects of dietary fiber source levels on the fecal ammonia nitrogen, growth performance, carcass traits, gastrointestinal tract development, and intestinal morphology of broilers. A total of 420 one-day-old unsexed broiler chicks were individually weighed and randomly divided into 5 groups, each with seven replicates of twelve chicks. Rice hulls (RH) and soybean hulls (SH) were ground through a hammer mill with a 2-mm screen. The RH and SH experimental diets were as follows: 0% (control); 2.5% RH; 2.5% SH; 5% RH; and 5% SH. No significant differences were found in growth performance and fecal ammonia nitrogen among the dietary treatment groups (p>0.05). Compared with the control, the experimental diets with 2.5% SH significantly decreased the wing weight of chickens (p<0.05), while no significant differences in the weight of the other visceral organs were observed. Compared with the control, broilers in the 5% SH group had a longer jejunum and ileum (p<0.05). Feeding the broilers SH and RH had no effect on the villus area and crypt depth of the intestine. Compared with the control, the experimental diet with 2.5% RH significantly increased the duodenal villus height of chickens (p<0.05). These findings suggest that the inclusion of 5% SH in the diets resulted in improved intestinal morphology without negatively affecting growth performance and carcass traits.

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.

The effects of dietary untreated whole-grain paddy rice (WPR) on performance and histological intestinal alterations were investigated in Sanuki Cochin male chicks. At 2 weeks of age, chicks showing similar body weights were randomly divided into 3 groups of 10 birds each. The control group was fed with a basal diet (starter diet: CP 21%, ME 3000 kcal/kg; grower diet: CP 18%, ME 2850 kcal/kg; finisher diet: CP 15%, ME 2800 kcal/kg) and the other groups were fed with the basal diet diluted with WPR at 20% (starter diet: CP 17.8%, ME 2958 kcal/kg; grower diet: CP 15.4%, ME 2838 kcal/kg; finisher diet: CP 13%, ME 2798 kcal/kg) and 40% (starter diet: CP 14.6%, ME 2916 kcal/kg; grower diet: CP 12.8%, ME 2826 kcal/kg; finisher diet: CP 11%, ME 2796 kcal/kg). They were housed in individual cages under natural room temperature (around 5℃) with a daily lighting regimen of 16 h of light and 8 h of dark. The growth performance, relative length of the intestines and relative weight of the visceral organs to 100 g body weight did not differ except that the weight of the gizzard increased significantly (p＜0.05) in the WPR groups. Most parameters of villus height, villus area, cell area and cell mitosis numbers of the WPR groups did not show a significant decrease. In scanning electron microscopic results, the morphology of the villus apical surface in the WPR groups did not show damage due to WPR and had similar cells to the control (protuberated cells). These results demonstrate that WPR can be diluted by up to 40% as a feed ingredient in chicken basal diets.

Two experiments were conducted to investigate the effect of replacing corn with whole-grain paddy rice (WPR) in laying hen diets on egg production performance and quality. Commercial layers (Sonia) were used in both Experiment 1 and 2. In Experiment 1, 80 layers were placed into 4 groups of 20 birds each: the corn in the basal diet was replaced with 0, 10, 30 and 50%WPR. Each group of 20 birds had 10 replicates of 2 birds. In Experiment 2, 45 layers were placed into 3 groups of 15 birds each: the corn in the basal diet was replaced with 0, 70 and 100%WPR. Egg production was recorded daily and feed consumption was measured weekly throughout the experiments. Eggs from each group were collected biweekly to measure egg quality. Egg production performance and quality were not different among the groups (P>0.05), except for a decreased (P<0.05) shell ratio in the 100%WPR group. Moreover, yolk color score decreased (P<0.05) with increasing levels of WPR (50%WPR or more). The present results reveal that WPR can replace up to 100% of corn in laying hen diets without harming egg production performance and quality.