SAEVA Congress 2018 Proceedings | 12-15 February 2018 | ATKV Goudini Spa
decibel level of each of those frequencies on the y-axis as shown below. The red
line represents inhalation and the blue line represents exhalation. The lower figure is
the PSD graph of a horse with an axial deviation of the vocal cord or “whistle”. Note
the increase in decibels at about 2.0kHz during inhalation with no corresponding
peak on the blue line (exhalation). This technique has proved to be a useful, non-
invasive tool for recording and analyzing respiratory sounds made by exercising
horses under field conditions.
The recording equipment was well tolerated by all horses regardless of age or
gender, although mild head-shaking by the occasional horse before the high-speed
portion of the exercise event can occur and certain environmental factors can limit its
application when performing audio recordings under field conditions.
The
microphone did not function in the rain and intense heat had an adverse effect on the
micro-cassettes.
Figures courtesy of Dr. Deborah Boehler, Equine Analysis LLC, Midway, KY USA
Not only was the test non-invasive and the equipment easy to attach, but multiple
horses can be tested simultaneously to see how the upper airway performs under a
mock racing scenario. Screening of horses undergoing high-speed exercise using
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