I don't have any personal knowledge of this, but your question interested
me.  I did a quick search and found this site for a "silent" dog whistle
that is used for training dogs but uses a frequency too high for human ears.
However, the ad includes this statement:  "The Acme Silent Dog Whistle
produces ultra high frequencies in the range of 5800Hz. to 12400Hz. Used for
training dolphins and killer whales at Sea World it is also famous for its
effects on cats, horses, mice and even bats! "
http://www.ewhistles.com/store/iw-11006.html

Based on that statement, I would guess that your cats will also hear the
whistle.  However, the one in the ad is a training whistle and other sources
indicate that there are varying reactions (from no reaction at all to a
reaction of coming immediately to the person holding the whistle -- which
isn't the reaction you want).  Is the one you are considering a training
whistle with varying degrees of sound, as this one is?  If so, I'm not sure
if you would get the desired reaction (which is "stop barking").  You could
try it and keep a close eye on your cat to see if there is any reaction.

MaryL

no they do not have the same  hearing

Lisa C;553066 Wrote:

Cats can hear dog whistle also, but may be sensitive on a differen
pitch. Even not all dogs are sensitive on the same pitch. There i
sound frequency they hate the most but it differs from dog to dog. Th
best results in stopping them barking is to use multifunctional do
whistle which has sixteen selectable sound frequencies. You can find i
at: http://schweizer-dog-whistle.azpromo.hr/
With a little experiment you can find the right frequency for you
neighbor's dog. It is very small chance that your cat will be sensitiv
on this pitch too.
And, if you don't blow the whistle right in your cat's face with you
full power, you can't hurt your kitty

--
Savitri