The immunomodulatory
effects of propolis and probiotic were confirmed previously
(Sforcin, 2007; Koenen et al., 2004). Propolis samples used in
the present study were a rich source of phenolic compounds
(Table 1) which have been confirmed to be responsible for the
immune properties of propolis (Oršolic et al., 2004). The
aggregation of probiotic and propolis in the poultry diet
caused an increase in both lymphatic organ relative weight
and immune response to NDV. Thus, it could be concluded
that the combination of probiotic and propolis extract boosts
immune function. RBC and hematocrit levels were not
affected by the experimental diets.