Studies on Some Probiotics in Prevention of Enterobacteriaceae Inefctions in Broiler Chickens

This work aimed to study the role of probiotics on caecal pH value,growth performance, immune response post vaccination, phagocyticactivity, histopathological changes and prevention of E. coli & Salmonellainfections in broiler chickens. The results were:1- Significant decrease in caecal pH value in all treated groups withprobiotics2- Slight improvement in mean body weight, feed intake and FeR INprobiotic treated chickens.3- Significant increase in ND-GMT antibodies was recorded afterprobiotic treatment.4- Histopathological investigation of probiotic treated chickens showedthat the intestinal villi become more taller and thicker with presence ofgoblet cells and numerous lymphocytes when compared with control.5- Significant decrease in mean bacterial count of E.coli in caecal contentof probiotic treated & E.coli infected chickens along 6 weeks rangedfrom (4.52±0.20 to 0) when compared with E.coli infected control(7.99±0.50 to 1.90±0.61) respectively.6- Significant decrease in E.coli reisolation from the caecum of probiotictreated & infected chickens ranged from (20±0.10 to 13.33±0.33) andfrom liver was (20±0.65 to 10±0.95) when compared with E.coliinfected control (66.67 ± 0.39 from caecum and 56.67 ± 0.82 from the