大恒肉鸡对不同来源菜籽粕的代谢能和氨基酸营养价值评定

Evaluation of Metabolizable Energy and Amino Acids Nutrient Value of Different Rapeseed Meals for Daheng Broilers

本试验旨在运用真代谢能(TME)法研究大恒肉鸡对不同来源菜籽粕的代谢能(ME)和氨基酸营养价值的评定。从四川省的饲料企业随机收集12个菜籽粕样品,评定其ME和氨基酸真利用率(TAAA)。ME评定:分3批代谢试验,每批48只正常鸡,随机分为6个组,每组8个重复,每个重复1只鸡。TAAA评定:分3批代谢试验,每批36只去盲肠鸡,随机分为6个组,每组6个重复,每个重复1只鸡。每批做1个内源组,每批之间设10 d恢复期。试验采用TME法测定ME,试验鸡饥饿48 h,然后按体重2%强饲待测饲粮,收集排泄物48 h;内源组鸡饥饿48 h,再继续饥饿收集排泄物48 h。结果显示:1)12个菜籽粕样品的干物质(DM)、粗蛋白质(CP)、总能(GE)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)、粗纤维(CF)、粗脂肪(EE)和粗灰分(ash)的平均含量分别为87.67%、42.10%、19.75 MJ/kg、39.99%、16.13%、15.15%、2.40%和9.10%;其中,NDF、ADF、EE和ash的变异系数(CV)大于15%。2)12个菜籽粕样品的表观代谢能(AME)、氮矫正表观代谢能(AMEn)、TME和氮矫正真代谢能(TMEn)的平均值分别为8.627、9.029、9.326和8.970 M J/kg,不同来源菜籽粕的M E差异显著(P<0.05)。3)12个菜籽粕样品的氨基酸的平均含量为0.72%~6.55%,赖氨酸的CV最大,为18.97%。4)12个菜籽粕样品的TAAA的平均值为68.37%~88.92%,不同来源菜籽粕的TAAA差异显著(除蛋氨酸、苏氨酸和丝氨酸外)(P<0.05);必需氨基酸真利用率的平均值为70.81%,非必需氨基酸真利用率的平均值为70.43%,总氨基酸真利用率的平均值为70.45%。以上结果表明:1)不同来源菜籽粕的AME、AMEn、TME和TMEn存在差异;2)大恒肉鸡对不同来源菜籽粕的TAAA存在差异。

This study was conducted to evaluate metabolizable energy （ME） and amino acids nutritent value of different rapeseed meals for Daheng broilers by using true ME （TME） assay. Twelve rapeseed meal samples were collected from feed enterprises in Sichuan province and its ME and true availabilities of amino acid （ TA- AA ） were determined. ME evaluation included 3 batches metabolic test, 48 normal broilers per batch were ran- domly assigned to 6 groups with 8 replicates per group and 1 chicken per replicate. TAAA evaluation included 3 batches metabolic test, 36 caecectomized broilers per batch were randomly assigned to 6 groups with 6 repli- cates per group and l chicken per replicate. An endogenous group was prepared in every batch, and 10-day re- covery between each batch was set up. TME assay was used to investigate the ME, including feed withdrawal for 48 h before feeding test samples and then 2% of body weight of diets to be measured for force feeding, with 48 h of excreta collection period; whereas the group for endogenous collection was continued to fast and collected the excreta for 48 h. The results showed as follows： 1 ） The mean contents of dry matter （DM）, crude protein （ CP）, gross energy （ GE）, neutral detergent fiber （ NDF）, acid detergent fiber （ ADF）, crude fiber （CF） , ether extract （EE） and ash of 12 rapeseed meal samples were 87.67%, 42.10%, 19.75 MJ/kg, 39.99%, 16.13%, 15.15%, 2.40% and 9.10%, respectively. The coefficient of variation （CV） of NDF, ADF, EE and ash were greater than 15%. 2 ） The means of apparent ME （AME）, nitrogen corrected AME （AMEn）, TME and nitrogen corrected TME （TMEn） of 12 rapeseed meal samples were 8.627, 9.029, 9.326, and 8. 970 MJ/kg, respectively. There was significant difference in ME of different rapeseed meals （P〈0.05）. 3） The mean contents of amino acids of 12 rapeseed meal samples were ranged from 0.72% to 6.55%. The maximum CV of lysine was 18.97%. 4） The means of TAAA of 12 rapeseed meal samples were ranged from 68.37% to 88.92%. There was significant difference in TAAA of different rapeseed meals except for methionine, threonine and serine （P〈0.05）. The means of true availabilities of essential amino acids, non- essential amino acids and total amino acids were 70.81%, 70.43%, and 70.45%, respectively. It is concluded that： 1 ） there are differences in AME, AMEn, TME, and TMEn of different rapeseed meals. 2 ） There are differences in TAAA of different raoeseed meals for Dahene broilers.