Speciemens of hydatid cysts were collected from infected liver and lung of cattle , multilocullar cysts , different sizes , milky Replacement Windows in coulor , some of them superficial while others embedded in the parenchyma of the organs.Bacteria were isolated from liver and lung infected with hydatid cysts in cattle slaughterd in Diwania slaughter house.S.aureus and C.Pyogenes were isolated from the liver , while Streptococcus spp and C.
pyogenes were isolated from lung hydatid cysts.Bacterial colonies were identified by culturing on enriched and selective media with various biochemical tests.All bacterial species were sensitive to Ciprofloxacin and Genta- mycin While it is resistant to Carbencillin and Ampicillin.Histopathological study revealed the hydatid cysts in liver and the lung were surrounded by fibrous Bundt Pans tissue.Coagulative necrosis were noticed in liver tissue while casouse necrosis was in lung tissue.