Regression Method Used To Determine The Net Energy Requirement For Maintenance And Determination Of Retained Net Energy Of Protein Feed Related To Research Of Exactly Substitution Ratio

(Animal Nutrition Institute, Sichuan Agricultural University, Ya'an 625014,China)Abstract:This experiment was conducted to study regression method used to determine the net energy requirement for maintenance for 0-21-d-old male Chinese Color-feathered Chicks; To establish crude protein levels of basal diet and exactly substitution ratio when using methods of substitution to evaluate net energy value of soybean meal. Two experiments were carried out to achieve that:regression method used to determine the net energy requirement for maintenance for 0-21-d-old Chinese Color-feathered Chicks. Eighty five 8-d-old (empty body weighted 42±1 g) male Chinese color-feathered chicks were used in this experiment, five birds were killed by cervical dislocation and cryopreservation to regard as control, remaining Eighty brids were randomly assigned to four treatments with five replicates each, each replicate containing four chicks. Four treatments were divided into ad libitum intake, 30%,50%, and 70%of restricted feeding respectively. CP level of basal diet was 17%. The birds were fed to 14.5 day of age, fasting 36 hours (16 day of age). All of birds were killed by cervical dislocation and cryopreservation. The length of the experimental period was from 8 to 16 days of age, total 7 days. Comparative Slaughter were applied to determine the retained energy in experimental period.To establish crude protein levels of basal diet and exactly substitution ratio when using methods of substitution to evaluate net energy value of soybean meal. Tested chicks in different treatments were fed basal diet, which was substituted by different ratio of tested feedstuff (0%,10%,20%,30%and 40%). Sixty five 8-d-old (empty body weighted 45±1 g) male Chinese color-feathered chicks were used in this experiment, five birds were killed by cervical dislocation and cryopreservation to regard as control, remaining sixty brids were randomly assigned to five treatments with six replicates each, each containing two chicks. The. birds were fed to 14.5 day of age, fasting 36 hours (16 day of age). All of birds were killed by cervical dislocation and cryopreservation. The length of the experimental period was from 8 to 16 days of age, total 7 days. Comparative Slaughter were applied to determine the retained energy in experimental period.The results showed that 1) The results showed that Regression equation of NEm is HP=357.61e0001MEI(R2=0.98, P<0.01),NEm=357.61 KJ/kgBW0.75perd for 0-21-d-old Chinese Color-feathered Chicks at 30±2℃.2) The AME value of tested feedstuff decreased linearly (P<0.01) as the substitution ratio of soybean meal increased. The AME value of soybean meal was 9.60 MJ/kg by using method of extrapolation. The average AME value was 10.12 MJ/kg by using method of substitution.3) Substitution ratio of 20%group achieved the highest NE value. Compare with 0%and 10%substitution ratio groups, no significant difference of NE Value was showed (P>0.05), while comparing with 30%and 40%substitution ratio groups, NE value was significantly higher (P<0.01). The NE value of soybean meal was 6.25 MJ/kg as tested soybean meal substitution 20% in basal diet.Conclusion:Exactly substitution ratio is 20%when used method of Substitution to evaluate Net Energy Value of Soybean Meal. Crude protein levels of basal diet is after substitute 20%can be satisfied with requirement of animal normal physiological.