Bacterial species most commonly associated with the Bovine Respiratory Disease are P. multocida and M. haemolytica. Both are causing bronchopneumonia, acute fibrinonecrotic pleuropneumonia, hemorrhagic septicemia and septic infection in cattle. Because of the severity of these diseases, both bacterial species are known as primary pathogens. The objective in diagnosing these diseases involves identification of the causative agents. Delaying in diagnosis becomes a major factor in the severity and complication of BRD. Detection of the causative agents is also a complex process that depends on specimen collection, transportation, isolation and culture conditions, and phenotypic and genomic identification methods. During this research work, superior diagnostic techniques were introduced for accurate and fast diagnosis of the primary causative agents of BRD, mainly introduction of improved specimens transporting medium from field to laboratories, analyzed rapid biochemical test kit for its commercial production and application, and newly developed multiplex PCR for direct detection of both causative agents from field specimens.
