Environmental conditions may influence experimental outcomes in laboratory animals. In this study, we measured the effects of a vortex air-filtration device (AFD) on growth rate, morbidity, mortality, behavior, and gross pathology in P2a Leghorn chickens (Gallus gallus domesticus) raised from hatchlings to 6 wk of age. Growth rate was reduced in the group exposed to the operating AFD ('AFD on' group) compared with the 2 control groups ('AFD off' and 'Historical' groups). Similarly, 6-wk survival probability and body weight were decreased in the AFD-on group compared with controls. Splenic and cardiac weight indices were lower in the AFD-on and AFD-off groups compared with the Historical group. A progressive increase in the ambient sound level (Historical, 53.5 ± 1.7 dBA; AFD off, 63.6 ± 0.5 dBA; AFD on, 71.8 ± 0.8 dBA) was the only variable found to correlate with the physiologic differences observed across the 3 groups of growing chickens. These findings indicate that experimental outcomes with growing chickens are negatively affected by vortex air-filtration devices.