Comparison the effect of two herbal extracts, Propolis, Antibiotic and Coccidiostat on Immune System, Blood Parameters and Performance of Broiler Chickens Challenged with E. coli

The effects of the herbal extracts (Rosemary officinalis L., Salvia officinalis), propolis, virginiamycin antibiotic and the herbal coccidiostat were studied on broiler chickens challenged with two E. coli strains (O78K80 & O2K12). A total of 476 female cobb 500 broilers was allocated in a completely randomized design considering seven treatments with four replicates and 17 birds per each for 42 days. Negative and positive control groups received a basal diet with no supplementation. The two herbal groups received a basal diet with 1 mL of ethanol herbal extracts (Rosemarinus officinalis & Salvia officinalis) / L drinking water, respectively. The virginiamycin (10%), the herbal coccidiostat and the ethanol extract of propolis groups fed the basal diet plus 150, 200 and 500 mg / kg diet, respectively. All groups except negative control challenged with two E. coli strains (O78K80 & O2K12) in 14d of rearing period. Herbal extract decreased the intestinal population of E. coli and Salmonella compared to the positive control (P