Abstract

This study evaluated the effects of combined dietary supplementation with Nigella sativa seeds (NSS) and β-glucan (βG) on growth performance, intestinal histomorphology, oxidative status, immune responses to Newcastle disease (ND), avian influenza (AI), and infectious bursal disease (IBD), and protection against ND virus (NDV) challenge in broiler chickens. Ninety-six 1-day-old chicks were randomly allocated into three groups, with three replicates each: vaccinated control (G1), vaccinated and NSS/βG-supplemented (G2), and non-vaccinated, non-supplemented (G3). G3 was further divided into NDV-challenged positive controls (G3A) and negative controls (G3B). the G3 . All groups, except the negative controls, were challenged with NDV at 35 day of age (D). Dietary supplementation tended to enhance ND-, IBD-, and AI-specific antibody titers following vaccination. After NDV challenge, both vaccinated groups showed markedly reduced mortality compared with the positive control (40%), while G2 exhibited significantly lower oropharyngeal viral shedding than G1 (P

Key words: growth performance, Newcastle disease, virus, chickens, vaccine, Nigella sativa, β-glucan, infection