The Role of Some Bacteia In Chickens Respiratory Troubles and Recent Preventive Measures

In this study 155 chickens of different ages at Alex. and Sharkia governorate suffered from respiratory signs were examined for signs and PM lesions. Rapid serum plate test for Mycoplasma gallisepticum antibodies detection was done. Bacterological examinaSerological identification revealed E. coli O78: K80, S. Enteritidis, S. Kentucky and S. anatum. SPA test revealed presence of MG antibodies in 36.8% of examined cases.Pathogenicity test applied by isolated E. coli O78 & S. enteritidis (single or mixed infection) and the effect of infection (Single or mixed) on mortality, body weight, some biochemical (Total protein, Albumin, uric acid and creatinine) and immunological The preventive measures (sensitive antibiotics, E. coli vaccine and probiotic) were applied for protection against infection and their effect on mortality, body weight, some biochemical (Total protein, Albumin, uric acid and creatinine) and immunological The results revealed the following:• Mortality in mixed infection was 26.67% higher than single infection 20% with E. coli and 6.67% with Salmonella.• Reduction of body weight (18.05% - 23.83%) in E. coli and 9.34% – 18.58% in Salmonella and 19.42% – 29.51% in mixed infection with both E. coli and Salmonella.•Significant increase in immune response level (IgG, IgA) in all experimentally infected groups.