Airborne Dissemination of Bacteria (Enterococci, Staphylococci and ) in a Modern Broiler Farm and Its Environment.

The role of the air as a vehicle of bacteria dissemination in the farming environment has been previously reported, but still scarcely studied. This study investigated the bacteria density/diversity of the inside and outside air and of litter samples at a broiler farm. Samples were collected considering two seasons, three outside air distances (50/100/150 m) and the four cardinal directions. Selective media was used for staphylococci, enterococci, and recovery. A high number of bacteria was detected in the litter (2.9 × 10-5.8 × 10 cfu/g) and in the inside air (>10 cfu/m), but a low emission of bacteria was evidenced in the outside air (<6 cfu/m). Moreover, the bacteria detected in the farm's outside air decreased the further from the farm the sample was taken. A total of 544 isolates were identified by MALDI-TOF (146 from the litter, 142 from inside air and 256 from outside air). From these, 162 staphylococci (14 species; 40.7%), 176 (4 species; 66%) and 190 enterococci (4 species; 83%) were detected. was the predominant species, and identical PFGE clones were detected in inside and outside samples. The detection of identical DNA profiles in isolates from inside and outside samples suggests the role of the air in bacterial dissemination from the inside of the broiler farm to the immediate environment.