Effects of dietary supplementation with an expressed fusion peptide bovine lactoferricin–lactoferrampin on performance, immune function and intestinal mucosal morphology in piglets weaned at age 21 d

摘要

Lactoferrin has antimicrobial activity associated with peptide fragments lactoferricin (LFC) and lactoferrampin (LFA) released on digestion. Thesentwo fragments have been expressed in Photorhabdus luminescens as a fusion peptide linked to protein cipB. The construct cipB–LFC–LFA wasntested as an alternative to antimicrobial growth promoters in pig production. Sixty piglets with an average live body weight of 5·42 (SEM 0·59) kgnwere challenged with enterotoxigenic Escherichia coli and randomly assigned to four treatment groups fed a maize–soyabean meal diet containingneither no addition (C), cipB at 100mg/kg (C þ B), cipB–LFC–LFA at 100mg/kg (C þ L) or colistin sulfate at 100mg/kg (C þ CS) for 3 weeks.nCompared with C, dietary supplementation with C þ L for 3 weeks increased daily weight gain by 21%, increased recovery from diarrhoea,nenhanced serum glutathione peroxidase (GPx), peroxidase (POD) and total antioxidant content (T-AOC), liver GPx, POD, superoxide dismutasenand T-AOC, Fe, total Fe-binding capacity, IgA, IgG and IgM levels (P,0·05), decreased the concentration of E. coli in the ileum, caecum andncolon (P,0·05), increased the concentration of lactobacilli and bifidobacteria in the ileum, caecum and colon (P,0·05), and promoted develop-nment of the villus–crypt architecture of the small intestine. Growth performance was similar between C þ L- and C þ CS-supplemented pigs.nThe present results indicate that LFC–LFA is an effective alternative to the feed antibiotic CS for enhancing growth performance in pigletsnweaned at age 21 d.