Asthma in ferrets is generally not something that comes quickly and passes
quickly.  The cases that I have seen are generally seasonal, often coming
in sync with when the AC is turned on (late spring/early summer), for
unknown reasons.  These animals tend to cough rather than have a sneezing
fits, and X-rays show increased densities aroung the airways of the lung.
The animals often respond to sustained release bronchodilators and low
dose steroids.
 
Sneezing fits in ferrets are often, as you say, the result of environmental
dust, at least in my experience.
 
With kindest regards,
Bruce H. Williams, DVM, DACVP
 
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[Posted in FML issue 3397]