Study on Dynamic Prediction Model of Amino Acid Requirements for Jing Tint 6 Laying Hens from 7 to 12 Weeks of Age
Based on the principle of factorial method,a dynamic prediction model of amino acid requirements for Jing Tint 6 laying hens from 7 to 12 weeks of age was established by dividing nutrient requirement into growth requirement and maintenance requirement.In the growth requirement experiment,a total of 96 7-week-old Jing Tint 6 laying hens were randomly divided into 6 replicates with 16 chickens in each replicate and fed a basal diet.The experiment lasted from 7 to 12 weeks of age and was used to establish the amino acid growth re-quirement model.The maintenance requirement experiments were conducted once from 7 to 8 weeks of age,9 to 10 weeks of age and 11 to 12 weeks of age,and each 60 laying hens were randomly divided into restricted feeding group and nitrogen-free diet group with 6 replicates in each group and 5 chickens in each replicate.Each experiment lasted for 7 days,and the amino acid maintenance requirement model was established.Combi-ning the growth requirement and maintenance requirement of amino acids,the dynamic prediction model of a-mino acid requirements was established.The results showed as follows:1)the fitting equation of growth curve of laying hens from 7 to 12 weeks of age was BW,=3 224.649exp[-3.561exp(-0.012t)](R2=0.999),in which BW,was the body weight at t days of age(g),and t was the days of age.2)With the increase of days of age,there were no significant differences in amino acid patterns in the carcass and feathers of laying hens from 7 to 12 weeks of age(P＞0.05).3)The amino acid requirement model of laying hens from 7 to 12 weeks of age was TAAR={ 14.207exp[-3.561exp(-0.012t)-0.012t]+53.321exp[-7.122exp(-0.012t)-0.012t]} ×1 000×AAc/NPU+{-1.033exp[-3.561exp(-0.0121)-0.012t]+44.434exp[-7.122exp(-0.012t)-0.012t]} ×1 000xAAf/NPU+{ 19.67×{ 3 224.649exp[-3.561exp(-0.012t)]}0.75×AAm+C}/SID or TAAβ=(8×10-7BW2+0.004BW+0.706)×1 000×AAc/NPU+(-4× 10-6 BW2+0.009BW-2.936)× 1 000×AAf/NPU+(19.67×BW0.75×AAm+C)/SID,in which TAAR was the amino acid requirement(mg/d);AAc was the amino acid pattern in carcass(％);AAf was the amino acid pattern in feathers(％);NPU was the net protein utilization rate(％);AAm was the amino acid pattern for maintenance(％);C was creatinine excretion(mg/d);SID was amino acid digestibility(％);t was the days of age;BW was the body weight(g);BW0.75 was metabolic body weight(g).In summary,the dynamic prediction model of amino acid re-quirements for laying hens from 7 to 12 weeks of age is established by factorial method in this experiment.[Chinese Journal of Animal Nutrition,2024,36(11):7015-7027]
Jing Tint 6 laying hensfactorial methodamino acid requirementsdynamic prediction model
万方数据
维普
