L-Arginine Regulates Immune Functions in Chickens Immunized with Intermediate Strain of Infectious Bursal Disease Vaccine

Abstract

The present study investigated the effects of dietary arginine (Arg) supplementation on immune functions of broiler chickens inoculated with infectious bursal disease vaccine (IBDV). A total of 500 one-day-old female Ross (308) broilers were randomly assigned into 10 treatments (5 replicates per treatment, 10 birds per replicate). On day 14, birds were inoculated intramuscularly with IBDV or saline. Birds were fed diets containing one of five dietary Arg concentrations: 9.9, 13.9, 17.6, 21.3, or 25.3 g/kg respectively. The IBDV inoculation significantly reduced (P<0.05) serum lysozyme and IgA concentration, mitogen-stimulated peripheral blood mononuclear cell (PBMC) proliferation (Con A), PBMC in vitro NO and H2O2 yield, and serum anti-Newcastle disease virus (NDV) body titers. Increasing Arg concentration linearly increased (P<0.05) serum lysozyme concentration, quadratically increased (P<0.05) in vitro PBMC NO yield, linearly and quadratically increased (P<0.05) PBMC proliferation (LPS). Serum anti-IBDV antibody titers tended to be increased quadratically (P＝0.06) by increasing Arg concentration. The Arg requirement of IBDV inoculated chickens (18.9±0.5) for minimum FCR was higher (P<0.05) than that of un-inoculated chickens (16.0±1.3). The Arg requirements of IBDV inoculated chickens for the highest IgA concentration (17.5±0.6 g/kg) and PBMC proliferation (LPS) (19.8±2.1 g/kg) tended to be higher (P<0.10) than those for un-inoculated chickens (IgA: 16.1±0.6 g/kg; PBMC proliferation (LPS): 16.3±0.8 g/kg). These results indicate that dietary Arg supplementation may have a potential effect in alleviating IBDV-inoculation induced immunosuppression via enhancing the immune function of chickens.