Effect of Using Active Effective Microorganisms as an Alternative Antibiotics on Immunity in Local Domestic Fowls Nutrition

The main object of this work was to investigate the effect of adding two probiotics, (effective microorganism (EM) as a live microbes and Zinc bacitracin as antibiotic ) to the diets of Inshas chickens (a local Egyptian chicken strain) on chickens immunity. The experimental design consisted of six experimental groups: control and 5 dietary treatments as follows; (T1) Basal diet ( control ), (T2) Basal diet + EM (2.5 ml/kg diet ), (T3) Basal diet + EM (5.0 ml/kg diet ), (T4) Basal diet + EM (7.5 ml/kg diet ), (T5) Basal diet + EM (10.0 ml/kg diet ) and (T6) Basal diet + Zinc bactracin (500 mg/kg). Feeding treatment started at 4 wk of age and lasted at 41 wk. Characteristics investigations included : Immune response (immune response against NBVD and Cell-mediated immunity (Cutaneous basophil hypersensitivity CBH). Results obtained can be summarized as following ; It is clearly evidented that feed additives significantly improve the natural immunity of birds against viral invasions. An average antibody titer recorded in control diets was always significantly less than those found in all feed additives treatment (T2 to T6 diets ). Also, The addition of EM with different levels and Zinc bactracin to the chicks diet had significant increased in CMI response as compared with control , although in many cases Zinc bactracin seemed to be less effective than the EM.