Respiratory signs, swelling of infraorbital sinus and variable percentages of mortalities were observed in some turkey flocks in Behira, Egypt. This study aimed to investigate Avian influenza virus (AIV), Escherichia coli (E. coli), Salmonella, Avian metapneumovirus (aMPV), Mycoplasma gallisepticum (MG) and Mycoplasma meleagridis (MM) in suspected cases, followed by the genetic characterization of the detected microorganisms. AIV subtype H5N8 was detected from one backyard case that showed 100% mortality and was genetically classified under clade 2.3.4.4.b. Fourteen turkey farms that showed mortality percentages ranged between 7%-23% were tested for other pathogens, All of them were positive for E. coli isolation and negative for Salmonella isolation. Iuta and Iss virulence genes were present in 100% of  the tested E. coli isolates, while eaeA virulence gene was detected in 30% of these isolates. Antibiotic profiling of E. coli isolates revealed high sensitivity to Gentamicin, Erythromycin and Ciprofloxacin and high resistance with Tetracycline, Amoxicillin and Trimethoprim+Sulphadiazine. AMPV was detected in one farm. MG and MM were detected in 11 and 6 farms, respectively. Genetic analysis of mgc2 gene of 3 MG strains showed higher similarity with published Egyptian stains, ts-11 and 6/85 vaccinal strains. Also genetic sequencing of  the 16s rRNA gene of 3 MM strains showed 100% similarity with recently published Egyptian strains. MM isolation was successfully done in pure form, followed by PCR confirmation.  Further studies will be required to investigate  the spreading and pathogenicity of MM in Egypt.