Bacterial communities in PM2.5 and PM10 inside the cage broiler houses before and after disinfection

Background: Air in broiler houses is contaminated with considerable amounts of microbial aerosols, which affects the health of humans and birds. Thorough cleaning and disinfecting should be carried out to reduce particulate concentrations and minimize airborne microorganisms. Aims: To evaluate the effects of cleaning and disinfecting measures on bacterial communities in particulate matter less than 2.5 μm (PM2.5) and particulate matter between 2.5 and 10 μm (PM10) inside broiler houses. Methods: A mixed disinfectant (containing aldehydes, alcohol, and quaternary ammonium salt) was sprayed to decontaminate broiler cage houses. 16S rDNA amplicon sequencing was performed in this study to compare the bacterial communities in PM2.5 and PM10 before and after disinfection. Results: A variety of pathogens and opportunistic pathogens such as Staphylococcus, Streptococcus, Corynebacterium, Bordetella, Pseudomonas, and Shewanella were detected, the quantities of which were noticeably reduced but not eradicated after disinfection. In addition, the impacts on several pathogens and opportunistic pathogens in PM2.5 were not significant, which may be due to bacterial resistance to this type of disinfectant or other reasons discussed in the present study. Conclusion: Our results suggest that disinfection measures were effective in decontaminating air and further improving the feeding environment. This finding will help develop a reasonable disinfecting scheme for broiler houses.