<p>Abstract</p> <p>Background</p> <p>The presence of <it>Salmonella </it>enterica serovars in feed ingredients, products and processing facilities is a well recognized problem worldwide. In Norwegian feed factories, strict control measures are implemented to avoid establishment and spreading of <it>Salmonella </it>throughout the processing chain. There is limited knowledge on the presence and survival of the resident microflora in feed production plants. Information on interactions between <it>Salmonella </it>and other bacteria in feed production plants and how they affect survival and biofilm formation of <it>Salmonella </it>is also limited. The aim of this study was to identify resident microbiota found in feed production environments, and to compare the survival of resident flora strains and <it>Salmonella </it>to stress factors typically found in feed processing environments. Moreover, the role of dominant resident flora strains in the biofilm development of <it>Salmonella </it>was determined.</p> <p>Results</p> <p>Surface microflora characterization from two feed productions plants, by means of 16 S rDNA sequencing, revealed a wide diversity of bacteria. Survival, disinfection and biofilm formation experiments were conducted on selected dominant resident flora strains and <it>Salmonella</it>. Results showed higher survival properties by resident flora isolates for desiccation, and disinfection compared to <it>Salmonella </it>isolates. Dual-species biofilms favored <it>Salmonella </it>growth compared to <it>Salmonella </it>in mono-species biofilms, with biovolume increases of 2.8-fold and 3.2-fold in the presence of <it>Staphylococcus </it>and <it>Pseudomonas</it>, respectively.</p> <p>Conclusions</p> <p>These results offer an overview of the microflora composition found in feed industry processing environments, their survival under relevant stresses and their potential effect on biofilm formation in the presence of <it>Salmonella</it>. Eliminating the establishment of resident flora isolates in feed industry surfaces is therefore of interest for impeding conditions for <it>Salmonella </it>colonization and growth on feed industry surfaces. In-depth investigations are still needed to determine whether resident flora has a definite role in the persistence of <it>Salmonella </it>in feed processing environments.</p
