不同蛋白水平下平衡蛋氨酸和赖氨酸对生长早期皖西白鹅生长性能和氮代谢的影响

Effects of balanced methionine and lysine on growth performanceand nitrogen metabolism of Wanxi White geese under different protein levels

试验旨在研究不同饲粮蛋白水平下平衡蛋氨酸和赖氨酸对生长早期皖西白鹅生长性能和氮代谢的影响。选取180只1日龄的皖西白鹅,公、母各半,随机分成6组,每组5个重复,每个重复6只鹅。试验期28 d。试验采用双因素交叉设计,饲粮蛋白水平分别为20%、18%和16%,分别平衡赖氨酸或蛋氨酸。结果显示,与平衡赖氨酸组相比,平衡蛋氨酸组提高了平均日采食量(ADFI)和平均日增重(ADG)(P<0.01);20%蛋白水平组ADFI和ADG高于其他两组(P<0.01);18%蛋白水平组F/G极显著低于其他两组(P<0.01),氨基酸与蛋白水平在ADFI、ADG和F/G方面存在交互作用(P<0.01)。平衡赖氨酸组食入氮、沉积氮和氮利用率极显著高于平衡蛋氨酸组(P<0.01);20%蛋白水平组食入氮极显著高于其他两组(P<0.01),排出氮显著高于其他两组(P<0.05),沉积氮和氮利用率显著低于其他两组(P<0.01),氨基酸与蛋白水平在食入氮和沉积氮方面存在交互作用(P<0.01);平衡蛋氨酸组显著提高了蛋氨酸的利用率(P<0.01),20%蛋白水平组氨基酸利用率下降(P<0.01),氨基酸与蛋白水平在氨基酸利用率方面存在交互作用(P<0.01)。差异代谢物主要富集脂质、肽和有机酸通路,18%蛋白水平+平衡氨基酸组富集通路:丁酸代谢、神经活性配体受体相互作用、ABC转运蛋白、甘油磷脂代谢、α-亚麻酸代谢。赖氨酸是1~28日龄皖西白鹅的第一限制性氨基酸,18%蛋白水平+平衡赖氨酸(1.00%Lys+0.28%Met)更利于1~28日龄皖西白鹅的生长发育和氮代谢。研究表明,饲粮赖氨酸可上调与氮代谢呈显著正相关的特征性代谢物(如丁酸、脱氧腺苷、鸟嘌呤、甜菜碱等),蛋氨酸可上调与氮代谢呈显著负相关的特征性代谢物(如组氨酸、肌酸、3-羟基丁酸、黄嘌呤等)。

The experiment aims to investigate the effects of balanced methionine and lysine at different dietary protein levels on the growth performance and nitrogen metabolism of early Wanxi White geese.A total of 180 one-day-old Wanxi White geese were selected,with half males and half females,and randomly divided into six groups with five replicates in each group,with six geese in each replicate.The experimental period was 28 days.The experiment adopted a two factor crossover design,with feed protein levels of 20%,18%,and 16%,respectively,to balance lysine or methionine.The results showed that compared with the balanced lysine group,the balanced methionine group increased daily feed intake(ADFI)and daily weight gain(ADG)(P<0.01),the ADFI and ADG levels in the 20%protein level group were higher than those in the other two groups(P<0.01).The F/G of the 18%protein level group was extremely lower than the other two groups(P<0.01).There was interaction between amino acid and protein levels in ADFI,ADG and F/G(P<0.01).The intake of nitrogen,deposition of nitrogen,and nitrogen utilization efficiency in the balanced lysine group were extremely higher than those in the balanced methionine group(P<0.01).The 20%protein level group had extremely higher nitrogen intake than the other two groups(P<0.01),significantly higher nitrogen excretion than the other two groups(P<0.05),and significantly lower nitrogen deposition and utilization efficiency than the other two groups(P<0.01).There was an interaction between amino acids and protein levels of nitrogen intake and deposition(P<0.01).The balanced methionine group significantly increased the utilization rates of methionine(P<0.01),while the utilization rates of amino acids at the 20%protein level decreased(P<0.01).There was an interaction between the utilization rates of amino acids at the protein and amino acid levels(P<0.01).It was found that differential metabolites were mainly enriched in lipid,peptide,and organic acid pathways.The 18%protein level+balanced amino acid group enriched in pathways such as butyric acid metabolism,neuroactive ligand receptor interactions,ABC transporters,glycerophospholipid metabolism,and alpha linolenic acid metabolism.Lysine was the first limiting amino acid in 1~28 day old Wanxi White geese,and 18%protein level+balanced lysine(1.00%Lys+0.28%Met)was more conducive to the growth,development,and nitrogen metabolism of 1~28 day old Wanxi White geese.The study indicates that dietary lysine can upregulate characteristic metabolites significantly positively correlated with nitrogen metabolism(such as butyrate,deoxyadenosine,guanine,betaine,etc.),while methionine can upregulate characteristic metabolites significantly negatively correlated with nitrogen metabolism(such as histidine,creatine,3-hydroxybutyrate,xanthine,etc.).