The effect of different levels of Ziziphora (Thymus vulgaris) with commercial probiotic lactofeed on Newcastle and avian influenza titre of broilers challenged by dexamethasone Nazemi GH, Hedayati M* , KHalaji S Department of Animal Science, Faculty of Agricultural Sciences, Malayer University, Malayer, Iran. *Corresponding author's email: hedayati@malayeru.ac.ir, mahvet77@gmail.com Objectives: the aim of this study was, evaluated the effect of different levels of Ziziphora (Thymus vulgaris) with commercial probiotic lactofeed on humoral immunity of ND and AI of broiler challenged by dexamethasone. Materials & Methods: In this study 192 male broiler chicks Ross 308, in 8 treatments group and 4 replicates and 8 chicks in every replicates, and the treatments included: 1. Basal diet without any feed addetives and injection, 2. Basal diet plus 1.5% Ziziphora, 3. Basal diet plus 1% Ziziphora, 4. Basal diet with 0.02% lactofeed, 5. Basal diet with dexamthason injection, 6. Basal diet plus 1.5% Ziziphora and with dexamthason injection, 7. Basal diet plus 1% Ziziphora and with dexamthason injection, 8. Basal diet with 0.02% lactofeed and with dexamthason injection. Results & Conclusion: Results of this study, that showed, the injection of dexamthason decreased the humoral titre of ND and AI, significantly, also the Ziziphora powder and lactofeed were increased the ND titre and not sighnificant effect of AI. This study showed the dexamthason decreased titre, and, Ziziphora powder and lactofeed were increased, just ND titre.
