Effects of dietary energy and lysine on the performance and biochemical traits in growing-finishing pigs during constant high temperature period

The purpose of the experiment was to study the effect of the digestible energy and lysme on the performance and biochemical traits of growing-finishing pigs during constant high temperature period.Thtrty-two cross bred (Duroc×Long white×Large white)fatterting pigs.weighing an average of 44.1kg±1.8kg.were randomly assigned to four treatments.The level of the crude protem was 15.5%.The levels of energy were 13.23 MJ·kg1.13.73 MJ·kg1,14.93 MJ·kg-1.14.73 MJ·kg1,and the,levels of lysine were 0.676%.0.726%,0.764%.0.800% respectively.Results showed that:①High dietary energy and lysine level increased the body weight sigmficantly(P0.05)and decreased the Fecd/Gain ratio(P0.05).②With the increase of the dietary energy and lysine.the concentration of thyroxine(T3).total protein,globulin in the serum increased significantly(P0.05),and the concentration of Thyroxine(T4).glucose.albumin.increased insignificantly(P0.05).but the content of creatine kinase.triglyceride.Albumin/Globulin decreased significantly(P0.05).③With the increase of the dietary energy and lysine.serum K+ increased significantly(P0.05)and serum C1 decreased(P0.05),The energy and lysine had little effect on the serum Na+.④The energy and lysine increased the levels of blood antibody and lymphocyte ratio,and had a significant effect on Serum IgM(P0.05).and had a insignificant effect on the serum IgA.IgG and lvmphocvte ratio(P0.05).