Sixty random raw milk, kariesh cheese and Processed cheese samples (20 sample of each) were collected from different markets, groceries, villages and dairy farms of Sharkia governorate and examined for their bacteriological quality.1- Concerning the staphylococci count, the mean value in examined raw milk, kariesh and processed cheeses samples was 1.0x107, 5.0x105and 7.5x103, respectively. Meanwhile, Staph. aureus was isolated from 15.00, 20.00 and 0.00 % of the examined samples, reNon-infected chickens and treated with danofloxacin or ceftiofur sodium showed no gross pathological lesions. Most infected non-treated chickens revealed severe gross pathological lesions such as pericarditis, perihepatitis, air saculitis, and enteritis. 4- Body weight and body weight gain:The groups non-infected and treated with danofloxacin or ceftiofur sodium showed a significant increase in body weight. The groups infected with E.coli and non treated with danofloxacin or ceftiofur sodium evoked a significant decrease in the body weight.5-Effect on food consumption and feed conversion ratio:The group non-infected treated with danofloxacin or ceftiofur sodium showed an increase in food consumption and feed conversion ratio when compared with control group. The chickens experimentally infected with E.coli and non medicated showed a decrease inIII-Haematological picture:The groups non infected and treated with danofloxacin or ceftiofur sodium for three successive days revealed a significant decrease in erythrocyte count, haemoglobin concentration, packed cell volume with a significant increase in WBCs count all over the IV. Serum biochemical parameters:1- Liver enzymes:Groups non-infected treated with danofloxacin or ceftiofur sodium elicited a significant increase in AST, ALT, and ALP activities post treatment all over the experimental period. The groups infected with E.coli and non- medicated produced significant incr2-Total protein, albumin and globulin levels:The group non- infected treated with danofloxacin or ceftiofursodium showed a significant decrease in serum total protein and albumin levels with a significant increase in globulin levels post- infection all over the experimental period. Birds experimentally infected with E.coli and non- medicated evoked a significa3-Kidney function tests:Serum uric acid and creatinine levels were significantly increased as a result of treatment of normal chickens with danofloxacin or ceftiofur sodium. Infection of chickens with E.coli elicited a significant decrease in serum uric acid and creatinine levelElectrolytes:Danofloxacin or ceftiofur sodium administration to normal chicks displayed a significant decrease in Ca2+ level with a significant increase in ph2+ and Mg2+ levels. Chickens experimentally infected with E.coli and non- medicated showed a significant decreHistopathological findings:The liver section of the group non- infected treated with danofloxacin or ceftiofur sodium showed mild degenerative changes in the hepatic cells and the liver section of the group infected with E.coli non- treated showed severe degenerative changes and nu