Growth Performance and Intestinal Microflora Population of Broilers Fed Aged Brown Rice

Abstract The purpose of this study was to evaluate the growth performance and intestinal microflora population of broilers fed diets with aged brown rice (ABR) that had been stored for 3 years. The ABR was the material chosen to analyse the grain quality, which included the physical properties as well as nutrient analysis to evaluate its applicability in broiler diet. The germination rate, pH value, whiteness value of grains and fatty acid content of aged rice are significantly reduced during storage (P<0.05), while the nutritional value and content of essential amino acids do not differ from those of fresh brown rice (P>0.05). A total of five hundred 1-day-old broilers (Ross 308) were evenly divided by gender and randomly allocated into 5 groups (with 4 replicates of 25 birds), including: 1) control (corn-soybean meal), 2) 25% of corn replaced with 25% of ABR (ABR 25), 3) 50% of corn replaced with 50% of ABR (ABR 50), 4) 75% of corn replaced with 75% of ABR (ABR 75), 5) 100% of ABR replaced with yellow corn (ABR 100), respectively, in order to evaluate growth performance as well as intestinal microflora population of broilers fed ABR. The diets were formulated to contain similar levels of the main nutrient requirements of broilers. The results indicated that the replacement of ABR for corn in feed had no significant impact on the growth traits of broilers (P>0.05). The pH value of ileal digesta decreased as the replacement of ABR increased at the age of 21 days (P<0.05). The volatile fatty acids of ileal digesta of the ABR 75 and ABR 100 groups were significantly lower than those of the control group at the age of 21 days (P<0.05), but not caecum. There was no difference with lactic acid bacteria and coliform counts in ileum and caecum, respectively, of broilers among the groups during the entire feeding period (P>0.05). In conclusion, this study found that ABR may replace 100% of yellow corn and did not influence growth performance of broilers, thus providing an alternative for the use of stored rice in broiler diets.