Odor samples were collected two to four times per month over a one-year period in 2002-
2003 at three large open-lot beef cattle feedyards in the Texas panhandle. Samples were collected
using a vacuum chamber in 10 L Tedlar bags upwind of the feedyard, downwind of the pens, and
downwind of the runoff storage pond. Samples were analyzed in the odor lab for detection threshold
(DT) using triangular forced choice olfactometry with trained human odor panelists. Full-strength odor
samples were also analyzed for intensity and hedonic tone. Weather data was collected on-site at
each of the feedyards for correlation to odor characteristics. At two of the feedyards, mean upwind
DTs were similar to DTs downwind of the pens and storage pond, ranging from 24 to 30. At the third
feedyard, the mean upwind DT was 25, compared to 48 downwind of the pens and 84 downwind of
the pond. Results of the research indicate that DT alone may not be a good indicator of odor
characteristics and offensiveness from beef cattle feedyards.