Abstract:
The objective of the study was to investigate the effect of a probiotic ongrowth and
immune response of the broiler chicks vaccinated against Newcastle disease. Parameters of
investigation were weight gain, feed conversion ratio (FCR), live to dressed body weight ratio; weight
of various lymphoid organs i.e. Bursa of Fabricius, thymus and spleen; immune response of the
broilers. The findings were compared with the cyclophosphamide (cyc.) treated Newcastle disease
virus (NDV)-vaccinated; untreated and NDV-vaccinated; and the unvaccinated untreated control
chicks. The probiotic treated chicks showed higher mean body weights, better FCR, higher NDV HI
antibody titers, lesser overall mortality, no NDV post challenge mortality and no detrimental effects on
their lymphoid organs, compared to the cyclophosphamide treated and untreated chicks. Probiotic had
good effects on growth and immune response of the broilers.
