The objective of this study was to evaluate the effect of high digestible essential amino acids （DEAA） on weight gains and carcass compositions of laying hens. Three hundred and sixty lsa Brown hens in five replicat...The objective of this study was to evaluate the effect of high digestible essential amino acids （DEAA） on weight gains and carcass compositions of laying hens. Three hundred and sixty lsa Brown hens in five replications per treatment （12 birds/replicate） were used. Six experimental diets which contained of treatment 1 （negative control） as the conventional layer diet are recommended by NRC （1994） while another dietary treatments; treatments 2 （positive control）, 3, 4, 5 and 6 were formulated to meet 100%, 110%, 120%, 130% and 140% of Standard Ileal Digestible Lysine Levels （SIDLL） without crude protein minimum, while methionine （Met）, threonine （Thre） and tryptophan （Tryp） as related by Ideal Protein Concept （IPC） which suggested by NRC （1994） and INRA （2004）. However, metabolizable energy （ME）, calcium and available phosphorus （Avai P） levels of all experimental diets were meet requirement as recommended by NRC （1994）. The experiment was assigned in CRD and laying hens fed dietary treatments from 28 to 44 weeks of age and cage was the experimental unit （3 hens/cage）. The result shown that percentages of thigh （TP）, feet （FP）, drumstick （DP）, heart （HP）, liver （LP） and gizzard （GP） were not affected by dietary treatment. However, weight gains （WG） and percentage of dressed weight （DWP）, eviscerate weight （EWP） and breast （BP） were increased （P 〈 0.05） and abdominal fat was reduced （P 〈 0.05） when birds fad diets containing 130% of SIDLL as compared with control group and another dietary treatments, when increasing the DEAA levels upper to 130% of SIDLL. The result indicated that diets formulated without crude protein minimum and increased DEAA resulted in increasing the efficiency of converting metabolizable energy （ME） to net energy （NE） for increasing weight gain and improved meat products while fat deposition in carcass composition was reduced.展开更多
文摘The objective of this study was to evaluate the effect of high digestible essential amino acids （DEAA） on weight gains and carcass compositions of laying hens. Three hundred and sixty lsa Brown hens in five replications per treatment （12 birds/replicate） were used. Six experimental diets which contained of treatment 1 （negative control） as the conventional layer diet are recommended by NRC （1994） while another dietary treatments; treatments 2 （positive control）, 3, 4, 5 and 6 were formulated to meet 100%, 110%, 120%, 130% and 140% of Standard Ileal Digestible Lysine Levels （SIDLL） without crude protein minimum, while methionine （Met）, threonine （Thre） and tryptophan （Tryp） as related by Ideal Protein Concept （IPC） which suggested by NRC （1994） and INRA （2004）. However, metabolizable energy （ME）, calcium and available phosphorus （Avai P） levels of all experimental diets were meet requirement as recommended by NRC （1994）. The experiment was assigned in CRD and laying hens fed dietary treatments from 28 to 44 weeks of age and cage was the experimental unit （3 hens/cage）. The result shown that percentages of thigh （TP）, feet （FP）, drumstick （DP）, heart （HP）, liver （LP） and gizzard （GP） were not affected by dietary treatment. However, weight gains （WG） and percentage of dressed weight （DWP）, eviscerate weight （EWP） and breast （BP） were increased （P 〈 0.05） and abdominal fat was reduced （P 〈 0.05） when birds fad diets containing 130% of SIDLL as compared with control group and another dietary treatments, when increasing the DEAA levels upper to 130% of SIDLL. The result indicated that diets formulated without crude protein minimum and increased DEAA resulted in increasing the efficiency of converting metabolizable energy （ME） to net energy （NE） for increasing weight gain and improved meat products while fat deposition in carcass composition was reduced.
