Evaluation Of Corn Distillers Dried Grains With Solubles Produced In China For Layer

This experiment was conducted to determine the nutrient compositions of corn distillers dried grains with solubles (DDGS), which were widely used in China, and to establish prediction model for true metebobizable energy (TME) of DDGS and true digestible amino acid (TDAA) in poultry from proximate composition, in order to provide some valuable evidences for rational use of DDGS.Experiment 1 was conducted to measure color score, and the contents of GE, DM, Ash, CP, EE, CF, NDF, ADF and amino acid of twenty-five sources of DDGS obtained from different plants in China. The average content of GE, DM, Ash, CP, EE, NDF and ADF were 4641.96 kcal/kg, 87.44%, 4.81%, 27.91%, 15.22%, 6.35%, 37.58% and 10.61% respectively. Total amino acid (TAA) content (not including tryptophan) was 22.51%, essential amino acid (EAA) content was 8.99%, and non-essential amino acid (NEAA) content was 11.35%. Among 25 DDGS samples, the lowest EAA content was 6.28%, the highest was 9.88%, average was 8.99%, among EAA, Met was lowest (0.37%) but His (2.26%) was highest. The means of Color L*, A* and b* of 25 DDGS samples measured with a Chroma Meter were 47.00, 18.07 and 36.2. Results showed that, compared with the DDGS produced in abroad, the EE of DDGS produced in China was higer than of abroad, and there was not significant difference among other nutrient compositions. Color score could be used to predict the GE of DDGS, lighter and more yellow DDGS samples had higher energy content than darker DDGS. Compared with abroad, DDGS produced in China have much more variation in composition, especially in amino acid.In experiment 2, Single factor test design was used. Thirty-five cecectomized Hy-line brown roosters were randomly divided into 7 groups, with 5 replications per group and 1 bird per replication. Emptying-force-feeding method was used to measure TME and amino acid digestibility of DDGS in poultry. TME of DDGS ranged from 1779.46 to 3071.11 kcal/kg and averaged 2517.16 kcal/kg, CP true metabolic rate varied from 62.58 to 106.38% and averaged 79.50%. Total amino acid apparent digestibility was59.31%, true digestibility was 70.89%. The digestibility was lowest for Lys (55.94%), and highest for Arg (86.00%). The correlation between color score and amino acid content was not found. The results showed that the best single indicator of TME was GE (R~2=0.29). Prediction equation of TME of DDGS produced in China was TME = -799.43+1.14GE-40.10CF-56.12CP-23.02EE+6.22ADF-5.05NDF+ 83.50Ash (R~2 = 0.55,P<0.05). The content of amino acid of DDGS produced in China could not be evaluated with color score. Non-amino acid in crude protein limited the utilization of DDGS. The content of total amino acid and the value of crdue protein minus total amino acid could be used to predict the content of digestible amino acid.