LAUSR

INTRODUCTION AND PURPOSE Despite the various vaccination programs for protection against New Castle disease, it remains an important threat to the poultry industry. The ability of the probiotic bacteria to improve the immune system in both animals and humans supports their use as immune adjuvants for vaccination. The aim of the present study was to examine the effects of Lactobacillus acidophilus in ND vaccination. MATERIALS AND METHODS A total of 170 one day old chicks were divided in 5 groups. In groups A, B and C chicks were received L. acidophilus (5 × 109, 3 × 109 and 2 × 109) and also vaccinated with inactivated and attenuated ND vaccines. In group D, chicks only vaccinated without bacterial inoculation and group E was negative control with neither vaccine nor bacteria. Then IgG and HI NDV antibody titers were measured in all tested groups. RESULTS IgG and HI NDV antibody levels were significantly higher in Lactobacillus treated groups especially in group A with 5 × 109 bacteria, than only vaccinated and negative control groups. Also antibody levels against NDV increased during the vaccination period especially in probiotic treated groups. CONCLUSION In conclusion, L. acidophilus can use for improving immunogenicity of NDV vaccination programs.