利用饲料原料中的营养成分和可消化营养成分含量建立肉羊常用蛋白质饲料原料代谢能的预测模型

摘要

This experiment aimed to investigate the effects of nutrient and digestible nutrient contents of com?mon protein feedstuffs for mutton sheep on effective energy values using substitution method, and to establish the prediction model for metabolizable energy ( ME) of protein feedstuffs based on nutrient contents and digest?ible nutrients of feedstuffs. Thirty?six castrated Dorper×thin?tailed Han F1 crossbred rams with the body weight of (52.6±1.4) kg and the age of 22 months were randomly assigned to 6 treatments ( each treatment had 6 rams) with one treatment fed basal diet and the other 5 treatments fed experimental diets. Digestion and metab?olism experiment and respiration and metabolism experiment were conducted combined with substitution method to measure and calculate the digestible energy ( DE) and ME of individual protein feedstuffs. Correlation analy?sis was conducted between the contents of nutrients including dry matter ( DM) , organic matter ( OM) , gross energy ( GE) , crude protein ( CP) , ether extract ( EE) , neutral detergent fiber ( NDF) , acid detergent fiber ( ADF) , and digestible nutrients including digestible dry matter ( DDM) , digestible organ matter ( DOM) , digestible crude protein ( DCP) , digestible ether extract ( DEE) , digestible neutral detergent fiber ( DNDF) , digestible acid detergent fiber ( DADF) and DE or ME of protein feedstuffs. The results showed as follows:the OM, DDM, DOM and DCP contents of feedstuffs had extremely significant positive correlations with DE or ME ( P<0.01); moreover, the DADF content had an extremely significant negative correlation with DE ( P<0.01), and had a significant negative correlation with ME (P<0.05). The prediction equation of ME using nutrient contents of feedstuffs was: ME ( MJ/kg ) = - 82. 855 + 2. 391OM (%) + 1. 802EE (%) -6.21GE ( MJ/kg)-0.121ADF (%) ( R2=0.910, n=30, P<0.01) . The prediction equation of ME using di?gestible nutrient contents of feedstuffs was: ME ( MJ/kg)= -5.564+30. 526DOM (%)+55. 402DEE (%) (R2=0.841, n=30, P<0.01). The prediction equation of ME using digestible nutrient contents and DE of feedstuffs was: ME ( MJ/kg)= -5.787+1. 126DE ( MJ/kg)+20. 769DEE (%) ( R2=0. 879, n=30, P<0.01) . In conclusion, in this experiment, some nutrient and digestible nutrient contents of protein feedstuffs significantly correlated with ME, and they can be effectively used to predict the ME of protein feedstuffs for mutton sheep.%本试验应用套算法分析肉羊常用蛋白质饲料原料中的营养成分含量和可消化营养成分对有效能值的影响,基于饲料原料中的营养成分含量和可消化营养成分建立蛋白质饲料原料代谢能(ME)的预测模型.选取36只22月龄、体重为(52.6±1.4)kg的杜泊×小尾寒羊F1代杂交去势肉羊,采用完全随机区组设计分为6个处理,包括1个基础饲粮处理和5个试验饲粮处理,每个处理6只羊.利用消化代谢试验和呼吸代谢试验并结合套算法计算5种蛋白质饲料原料的消化能(DE)和ME,并分析蛋白质饲料原料DE、ME与该原料中营养成分[干物质(DM)、有机物(OM)、总能(GE)、粗蛋白质(CP)、粗脂肪(EE)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)]和可消化营养成分[可消化干物质(DDM)、可消化有机物(DOM)、可消化粗蛋白质(DCP)、可消化粗脂肪(DEE)、可消化中性洗涤纤维(DNDF)、可消化酸性洗涤纤维(DADF)]含量之间的相关关系.结果表明:饲料原料中的OM、DDM、DOM、DCP含量与DE和ME均存在极显著正相关(P<0.01);另外,DADF与DE存在极显著负相关(P<0.01),与ME存在显著负相关(P<0.05).通过饲料原料中的营养成分含量预测ME的方程为:ME(MJ/kg)=-82.855+2.391OM(%)+1.802EE(%)-6.21GE(MJ/kg)-0.121ADF(%)(R2=0.910,n=30,P<0.01);通过饲料原料中的可消化营养成分含量预测ME的方程为:ME(MJ/kg)=-5.564+30.526DOM(%)+55.402DEE(%)(R2=0.841,n=30,P<0.01);通过饲料原料中的可消化营养成分含量与DE共同预测ME的方程为:ME=-5.787+1.126DE(MJ/kg)+20.769DEE(%)(R2=0.879,n=30,P<0.01).综上所述,在本试验中,蛋白质饲料原料中的部分营养成分和可消化营养成分含量与ME之间存在显著相关,可通过饲料原料中的营养成分和可消化营养成分含量对肉羊蛋白质饲料原料的ME进行有效预测.