Evaluation of lactobacilli and active dry yeast in controlling e. coli infection in quails

الملخص EN

Two experiments were done to evaluate the efficacy of administration of active dry yeast and / or lactobacillus preparation (AVI-BAC), either before or after infection with antibiotic resistant strain of E.

coli (O127) in controlling the severity of infection in quail chicks.

The quail chicks in different experimental groups were infected orally and for 2 successive days with 3X107 CFU of E.

coli (O127), which was proved to be highly pathogenic for quails.

Each of the used probiotics was added in drinking water of different treatment groups in a concentration of 0.5 gm / l.

The results obtained revealed that the addition of lactobacillus or active dry yeast before E.

coli infection was highly effective in reducing the mortality rates, organ invasion and number of E.

coli positive quail chicks in addition to decrease the severity of macroscopic and microscopic lesions in different organs in the probiotic treated groups compared to the infected control and lactobacilli was more efficient in controlling the severity of infection.

On the other hand, the administration of yeast and /or lactobacilli or both after inducing E.

coli infection was reduced the mortality rates, the severity of lesions in different organs but failed to protect quail chicks against infection.

Also, it was proved that the two probiotics have synergistic effect in controlling collibacillosis in quails.