Effect of dietary antibacterial peptide and zinc-methionine on performance and serum biochemical parameters in piglets

The objective of this study was to evaluate the effect of dietary supplementation of antibacterial peptide and zinc methionine on performance and some serum biochemical parameters of weaned piglets. Rongchang male piglets (28 days of age, initial weight 8.4 +/- 0.65 kg) were used. All piglets were randomly allotted to four diets including the control group, the antibacterial peptide (AP) group containing 10 mg antibacterial peptide/kg diet, the zinc methionine (Zn-Met) group with 1 200 zinc methionine/kg diet (equal to 200 mg Zn2+/kg diet), the zinc methionine/antibacterial peptide (Zn/AP) group containing 10 mg antibacterial peptide and 1 200 mg zinc methionine/kg diet, respectively, in a 4-week feeding experiment. Each of these groups consisted of six replications with 8 pigs per replication. Average daily gain (ADG) and average daily feed intake (ADFI) both improved in the antibacterial peptide group (P < 0.05, P < 0.05), zinc methionine group (P < 0.05, P < 0.05) and zinc methionine/antibacterial peptide group (P < 0.01, P < 0.05), as compared with the control. Dietary zinc methionine also significantly reduced the diarrhoea ratio of piglets (P < 0.05). The serum immunoglobulin G (IgG) and superoxide dismutase (SOD) were increased (P < 0.05) and total cholesterol (TC) decreased (P < 0.05) in the antibacterial peptide group and zinc-methionine group, the high density lipoprotein (HDL) increased (P < 0.05) in the zinc methionine group, as compared with the control. The results indicated that antibacterial peptide and zinc methionine were effective in improving growth performance, enhancing immune function, blood vessel function and antioxidant enzyme activity of piglets.