RESUMO
Avian influenza [AI] [H5N1] outbreaks with very high mortality in twenty four [24] broiler flocks in Egypt provinces [El-Behira, El-Garbia, Kafer El-Sheikh, and Alexandria] were subjected to laboratory investigations in order to detect Enterobacteria associated with Avian influenza virus [AI] outbreaks in broiler flocks. Samples were collected from heart blood and liver for bacteriological examination. The samples for viral isolation were inoculated into specific pathogen free [SPF] embryonated chicken eggs [9-11 days old]. The allantoic fluids [AF] were harvested 36 hours post incubation and were tested by using Haemagglutination [HA] test, Haemagglutination-inhibition [HI] test, Agar gel precipitation test [AGPT] and Reverse Transcription Polymerase Chain Reaction [RTPCR]. Escherichia coli and Salmonella were determined by using a specific media for isolation and identification of both enterobacteria isolates. Twenty isolates out of twenty four [20 / 24] flocks which represent 83.33% of examined outbreaks having haemagglutination-inhibition titer by using avian influenza [AI] common type A antibodies ranging from 24 to28. The same isolates were also confirmed by Agar gel precipitation test [AGPT] and Reverse Transcription Polymerase Chain Reaction [RT-PCR]. A total of 16 samples out of 20 [16 / 20] [represented 80%] examined samples from broiler flocks associated with Avian influenza virus outbreaks proved to be E.coli while a total of 4 samples[4 / 20] [represented 20%] proved to be Salmonella enteritidis. The results of bacterial isolates were confirmed by biochemical test and serological identification