The Mensuration Of Net Energy Value Of Corn And Soybean Meal And Prediction Models For Broiler Chicken

To study the net energy(NE) of yellow feather broiler chicken,comparative slaughter was used to measure the net energy for maintenance(NEm) and net energy for production(NEp) of corn and soybean meal,and prediction models for NE by chemical characteristics or AME were established.In this study,the materials,which came from different area,were 9 corns and 8 soybean meals.256 male yellow feather broiler chicken,which had been fasted for 48 h and weighted 93±2.8 g,were selected as the experiment animals.To calculate the beginning value of energy of NEp,20 chicken whose average weight were same as the 256 chicken were selected and killed at the beginning of experiment.Then 20 chicken had been selected to measure NEm which offered basal diet until the morning of 13 d.10 of 20 chicken were fasted 48 h and killed, while the other 10 chicken were killed after they were fasted another 48 h.The residual 216 chicken,which were assigned randomly to 18 treatments,were used to measure NEp. Each treatment(diet) was consisted of 6 replicates with 2 birds each.Broiler chickens in different treatment were fed 10 d to test feedstuff substituted by different ration(corn: 30%;soybean meal:20%),and killed after they were fasted 48 h.Meanwhile,an enter method of multiple linear regression was applied to establish prediction equations for NE by chemical characteristics or with AME.The results showed that:1) The NE value of corn is 2.3747(2.1910～2.4678) (NEm:0.8508;NEp:1.5239)(Mcal/kg·DM),While the NE value of soybean meal is 1.1532(1.0835～1.2407)(NEm:0.8120;NEp:0.3412 )(Mcal/kg·DM);2) Correlation analysis showed AME is the better predictor for corn,while ADF is the better predictor, for soybean meal;3) The NE/AME of corn and soybean meal are 67%and 49% respectively;4) Multiple linear regression(Enter method) was applied to establish prediction equations for corn and soybean meal NE.Considering all the factors,we may safely come to the conclusion that the equation (NE=-0.767-0.327CF-1.279NDF+0.925AME(R~2=0.985,RSD=0.013)) and the equation(NE=0.640-0.792NDF-0.915ADF+0.399ST+0.286AME(R~2=0.998,RSD= 0.003)) are the better models for corn and soybean meal respectively.While we attempted to predict NE values directly from dietary chemical characteristics,the equation(NE=2.847-2.162NDF-8.650ADF+2.063EE(R~2=0.956,RSD=0.022))and the equation(NE=1.202-1.539ADF+0.559ST+1.701EE(R~2=0.996,RSD=0.004)) are the better models for corn and soybean meal respectively.