Evaluation Of Metabolic Energy And Standardized Ileal Amino Acid Digestibility For Broiler Chickens

The experiment was conducted to investigate the regression equations of apparent metabolic energy(AME),Nitrogen corrected metabolizable energy(AMEn)and standard of ileal amino acid digestibility of rice bran from six areas of the province of hunan in broiler chickens.In this experiment,560 AA broilers were randomly divided into seven treatments,including six rice bran group(A-F group),another N-free diet treatment which was used for determining ileal endogenous amino acid basal losses with 8 replicates per group and 10broiler chickens per replicate.The experiment adopted a single factor design.All of the diets were semi-purified and formulated with 0.5 percent titanium dioxideas an exogenous indicator.The trial lasted for 28 days.The first experiment studied the metabolic energy of rice bran from six different area in chickens at 13 and 27 day age.The formal trial was divided into two stages(11 to 13 day and 25 to 27 day),and adopted a total feces collection method to measure its apparent metabolizable energy(AME),nitrogen correction of metabolic energy(AMEn),then establishing the regression prediction equation of the AME and AMEn of broilers separately.The second experiment researched the apparent ileal amino acid digestibility(AID)and standard ileal amino acid digestibility(SID)of rice bran from six different area in chickens at age of 14 and 28 day,and using the terminal ileum chyme method to investigate amino acid digestibility at age of 14 and 28 day,then building the regression prediction equation about the AID and SID of rice bran at the two staged of chickens,respectively.The first experimental result showed that(1)the metabolic energy values of rice bran in the broiler chicken.At the age of 14 day,the average value of AME is10.54 MJ/kg,AMEn is 10.05 MJ/kg;at the age of 28 day,the average value of AME and AMEn is 11.50 MJ/kg and 10.98MJ/kg,respectively.(2)The regression prediction equation of the AME and AMEn at the age of 13 day:AME=20.18-0.35*NDF,R~2=0.85;AMEn=18.70-0.86*ADF,R~2=0.84.at the age of 27 day:AME=18.67-0.71*ADF,R~2=0.81;AMEn=18.08-0.71*ADF,R~2=0.80.The second trial showed that(1)The average value of the standard ileal essentially amino acid digestibility at age of 14 d:Arg 82.59%,His 83.49%,Ile 82.45%,Leu80.27%,Lys 79.87%,Met 87.42%,Phe 83.67%,Thr 81.40%,Trp 76.31%,Val 78.57%;At age of 28 d,The average value of the standard ileal essentially amino acid digestibility:Arg88.05%,His 89.76%,Ile 88.88%,Leu 87.21%,Lys 87.92%,Met 90.58%,Phe 89.41%,Thr86.30%,Trp 82.44%,Val 85.55%;(2)At the age of 14 day,the regression prediction equation of AID?SID are,respectively:AID Met=52.71+2.27*CP,R~2=0.81;AID Lys=114.38-3.27*CP+0.53*ST,R~2=0.98;AID Thr=6.85*CP+0.50*EE-30.51,R~2=0.90;AID Trp=286.97-12.54*CP-1.84*ADF,R~2=0.92.SID Met=53.59+2.24*CP,R~2=0.79;SID Lys=115.63-3.29*CP+0.52*ST,R~2=0.98;SID Thr=6.80*CP+0.50*EE-29.39,R~2=0.99;SID Trp=288.27-12.59*CP-1.87*ADF,R~2=0.92.the regression prediction equation of the AID?SID at the age of 28 day are,respectively:AID Met=67.25+1.54*CP,R~2=0.69;AID Lys=64.10+0.89*ST,R~2=0.61;AID Thr=25.33+3.82*CP+0.70*EE,R~2=0.96;AID Trp=246.53-9.59*CP-0.56*NDF,R~2=0.99.SID Lys=64.16+0.89*ST,R~2=0.61;SID Thr=25.58+3.32*CP+0.70*EE,R~2=0.96;SID Trp=247.48-9.63*CP-0.57*NDF,R~2=0.98.