عنوان مقاله [English]
Introduction Emerging low cost animal feed stock, originating from bioprocessing and food production is increasing on a global scale. In particular, dried distillers’ grains soluble (DDGS) is a by-product of the ethanol industry created in the fermentation process of cereal grains starch in dry mill ethanol plants. DDGS is defined as the product obtained after removal of ethyl alcohol by distillation from the yeast fermentation of a grain or a grain mixture by condensing and drying at least 75% of the resultant whole stillage by methods employed in the grain distilling industry. DDGS present a high concentration of energy, protein. Especially with respect to the original grains. DDGS are mainly obtained from corn, wheat, barley, sorghum and rice, as well as from grain blends. DDGS could be considered a poultry feed stuff as an alternative source of protein in poultry ration with other protein source or after dietary supplementation with lysine. The aim of this study is to investigate the effect of different levels of DDDS on performance and histology of jejunum in broiler chicken in starter, grower and finisher and analyzed DDGS.
Materials and Methods This experiment was done in 2 periods (first experiment was 1-21 days and second was 22-42 days). In first experiment 450 multiple Ross 308 broiler chicks were divided randomly into 5 experimental treatments and 6 replicates and second experiment had 5 treatment and 6 replicates and each replicate was assigned to a pen with 15 birds. Birds had given ad-libitum access to water drinking and diet. The experimental treatments received a basal diet that was supplemented as follows: control (without DDGS), 3%, 6%, 9% and 12% DDGS at first experiment and control (without DDGS), 5%, 10%, 15% and 20% DDGS at the second experiment. Prior to formulating the experimental diets, it was analyzed for dry matter, protein, amino acids, fat, crude fiber, ash. The amount of feed intake and body weight gain were measured weekly. At 21 and 45 days, 2 birds of each replicate were killed and intestinal segments removed. Samples (approximately 4 cm) were taken from the midpoint between the point of entry of the bile duct and Meckel's diverticulum (jejunum) for histology characteristics. Data were analyzed using GLM procedures of SAS software (SAS, 2006) in a completely randomized design. Differences between means were tested using Duncan’s test (1995). Differences were considered significant at P<0.05
Results and Discussion The chemical composition of the DDGS samples was determined at the beginning period. Crude protein, crude fat crude fiber, lysine and methionine were 30.5, 2.5, 3, 0.31 and 0.15% respectively. The differences between DDGS in this experiment with the others are depended upon plant species, genotype, climate, and stage of growth, the kind of soil and storage conditions. The results of the first experiment have shown that body weight gain increased in broiler fed 3% DDGS and control (847.31, 846.74). Results showed that 3% levels of DDGS fed to broilers increased body weight gain significantly from 11-21 d (P<0.05). The least body weight gain and feed intake was belonged to 12% DDGS vs. broilers fed 0, 3 and 6% DDGS from 1-21d. The feed intake decreased in broilers fed to 12% of DDGS in comparison to control groups and the other treatments. Feed conversion ratio was not significantly affected by treatments from 1-21 d. There was not any significant difference between feed conversion ratios in 1-21 day between treatments. There was significant difference (P<0.05) between body weight gain in 30-37 days old. The lowest and highest body weight gain observed in birds fed 20% and 5% DDGS, respectively. There was not any significant difference between feed intake and feed conversion in 22-45 days. Villus height decreased to 881.01 μm in 12% containing diets in comparison to the other treatments. Crypt depth was lowest in control (156.79 μm). Effect of DDGS on the histology of jejunum broiler chickens in 21 and 42 days was not significant. There was a tendency for an increased in crypt depth and decreased in villi height as dietary DDGS increased from 0 to 20%, however it was not significant.
Conclusion It can be concluded from this study, in first experiment (1-21 d) the dietary treatments containing 3% DDGS shows better performance in comparison to the other treatment. In second experiment (22-45%), 20% of DDGS was the best treatments for performance.