摘要
本试验旨在分析不同产地玉米的理化特性及育雏期蛋鸡对其氨基酸的表观回肠消化率(AID)和标准回肠消化率(SID),并基于物理特性和化学成分含量建立育雏期蛋鸡玉米氨基酸SID的预测方程。试验选取528只31日龄健康且体重[(284±10)g]相近的京红1号蛋雏鸡,随机分为11个组,每组6个重复,每个重复8只鸡。C0组饲喂无氮饲粮,C1~C10组饲喂不同产地玉米配制的半纯合试验饲粮,无氮饲粮和试验饲粮中均添加0.50%的二氧化钛(TiO_(2))作为外源指示剂,试验周期为3 d。试验结束后,使用二氧化碳(CO_(2))气体致晕并宰杀所有鸡只,采集回肠末端食糜测定氨基酸和TiO_(2)含量并计算氨基酸SID。结果表明:1)在风干基础下,10种玉米总能(GE)平均值为19.29 MJ/kg(18.03~23.81 MJ/kg),干物质(DM)、粗蛋白质(CP)、粗脂肪(EE)、粗灰分(Ash)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)、总磷(TP)、钙(Ca)和总淀粉(TS)含量平均值分别为86.95%(84.45%~89.24%)、7.96%(6.89%~9.52%)、3.43%(2.03%~4.50%)、1.26%(1.00%~1.58%)、8.12%(7.50%~9.52%)、2.40%(1.86%~3.66%)、0.26%(0.18%~0.31%)、0.05%(0.01%~0.13%)和65.93%(56.75%~70.64%),容重平均值为756.47 g/L(695.19~799.18 g/L),千粒容积平均值为446.40 mL/千粒(364.00~504.00 mL/千粒),千粒重平均值为337.90 g/千粒(250.15~381.55 g/千粒);玉米中必需氨基酸含量平均值为蛋氨酸0.16%(0.10%~0.21%)、赖氨酸0.25%(0.22%~0.32%)、苏氨酸0.31%(0.26%~0.40%)、色氨酸0.06%(0.05%~0.08%)。2)育雏期蛋鸡对玉米氨基酸SID为蛋氨酸92.35%、赖氨酸87.85%、苏氨酸82.86%、色氨酸83.98%。3)育雏期蛋鸡对玉米中17种氨基酸的SID预测方程的决定系数(R^(2))在0.663~0.965,其中丝氨酸SID预测方程的拟合度最高(SID=79.130+0.541GE+7.144Ash-2.767NDF+49.646甘氨酸,R^(2)=0.965,P<0.01),且苯丙氨酸、缬氨酸和半胱氨酸SID预测方程的R^(2)均超过0.90,拟合度好。综上所述,不同产地玉米的物理特性和化学成分变异较大,这是造成育雏期蛋鸡对不同产地玉米氨基酸AID和SID差异大的主要原因,其中玉米GE和CP、EE、ADF、NDF、TS及部分氨基酸含量可作为育雏期蛋鸡对玉米氨基酸SID预测的关键因子。
This study was to evaluate the physicochemical characteristics of corns from different producing areas and their apparent ileal digestibility(AID)and standardized ileal digestibility(SID)of amino acids in layer chickens during brooding period,and to build prediction equations of amino acid SID based on physical characteristics and chemical composition contents of corns.A total of 528 healthy Jinghong No.1 chicks of 31-day-old with similar body weight of(284±10)g were randomly divided into 11 groups with 6 replicates per group and 8 chickens per replicate.Chickens in C0 group were fed a nitrogen-free diet,and those in C1 to C10 groups were fed semi-homozygous experimental diets prepared with corns from different producing areas.Besides,0.50%titanium dioxide(TiO_(2))was added to both the nitrogen-free diet and experimental diets as exogenous indicator.The experiment lasted for 3 days.After the experiment,all chickens were stunned with carbon dioxide(CO_(2))gas and then slaughtered.The chyme at the end of the ileum was collected to determine the contents of amino acids and TiO_(2) to calculate amino acid SID.The results showed as follows:1)under the air-dry basis,on average,the 10 kinds of corns contained 19.29 MJ/kg(18.03 to 23.81 MJ/kg)gross energy(GE),86.95%(84.45%to 89.24%)dry matter(DM),7.96%(6.89%to 9.52%)crude protein(CP),3.43%(2.03%to 4.50%)ether extract(EE),1.26%(1.00%to 1.58%)crude ash(Ash),8.12%(7.50%to 9.52%)neutral detergent fiber(NDF),2.40%(1.86%to 3.66%)acid detergent fiber(ADF),0.26%(0.18%to 0.31%)total phosphorus(TP),0.05%(0.01%to 0.13%)calcium(Ca)and 65.93%(56.75%to 70.64%)total starch(TS),and the bulk density,1000 grain volume and 1000 grain weight of corns were 756.47 g/L(695.19 to 799.18 g/L),446.40 mL/1000 grains(364.00 to 504.00 mL/1000 grains)and 337.90 g/1000 grains(250.15 to 381.55 g/1000 grains),respectively.Some essential amino acid contents in corns were 0.16%(0.10%to 0.21%)for methionine,0.25%(0.22%to 0.32%)for lysine,0.31%(0.26%to 0.40%)for threonine and 0.06%(0.05%to 0.08%)for tryptophan,respectively.2)The amino acid SID of corns in layer chickens during brooding period was 92.35%for methionine,87.85%for lysine,82.86%for threonine and 83.98%for tryptophan,respectively.3)The determination coefficient(R^(2))of SID prediction equations for 17 amino acids of corns in layer chickens was ranged from 0.663 to 0.965,in which the serine SID prediction equation had the highest fitting degree(SID=79.130+0.541GE+7.144Ash-2.767NDF+49.646glycine,R^(2)=0.965,P<0.01),and the R^(2) of SID prediction equations of phenylalanine,valine and cystine was exceeded 0.90,indicating a good fit.In conclusion,this study confirms the large variation in physical characteristics and chemical composition of corns from different producing areas,which is the main reason for the difference in AID and SID of amino acids of corns from different producing areas in layer chickens during brooding period.Among them,the GE and contents of CP,EE,ADF,NDF,TS and some amino acids in corns can be used as key predictors of amino acid SID.
作者
潘泳霖
高峰
邢通
赵良
周岩民
顾玲
张林
PAN Yonglin;GAO Feng;XING Tong;ZHAO Liang;ZHOU Yanmin;GU Ling;ZHANG Lin(Jiangsu Collaborative Innovation Center of Meat Production and Processing,Quality and Safety Control,Key Laboratory of Animal Origin Food Production and Safety Guarantee of Jiangsu Province,College of Animal Science and Technology,Nanjing Agricultural University,Nanjing 210095,China)
出处
《动物营养学报》
CAS
CSCD
北大核心
2024年第9期5693-5708,共16页
CHINESE JOURNAL OF ANIMAL NUTRITION
基金
国家重点研发计划项目(2021YFD1300204)
江苏现代农业(蛋鸡)产业技术体系项目(JATS[2023]425)。
关键词
育雏期蛋鸡
玉米
理化特性
氨基酸消化率
预测方程
layer chickens during brooding period
corn
physicochemical characteristics
amino acid digestibility
prediction equation
