Horses have a keen sense of taste as well as smell. It is
much more highly developed in horses than in humans. Smell
is processed in a horse’s moist nostrils, which have
a very large surface area. Odor particulates are carried through
the air and deposited on the moist tissues, and the information
is sent to the brain for decoding. When an odor is particularly
intriguing a horse will curl back the top lip and raise its
head which enables it to use it’s Jacobson’s organ
more effectively. This organ is found towards the top of the
nasal passages. It makes the horse look like they are laughing,
but this is a smelling posture and is called the ‘flehmen.’
Taste is processed by papillae on the tongue, throat, and
the palate. Foods and liquids that the horse ingests pass
over the tongue and are either accepted or rejected. Horses
naturally like salty and quickly learn to like sweet, but
generally don’t like bitter or sour. Many horses love
the taste of peppermint hard candies.
Horses can not vomit, which is unfortunate as their stomachs
are highly sensitive to mold, bacteria slime and algae. The
senses of smell and taste protect most horses from the multitude
of poisonous plants that populate and border pastures. If
there is sufficient high quality grass and forage, a horse
will tend to avoid eating odd plants or spoiled, moldy plants.
Unless horses are very hungry or thirsty they generally won’t
eat feed or water that is ‘off’ or contaminated.
Horses can detect subtle differences in the mineral content
and, depending on the horse, he might refuse to drink unfamiliar
water. If you travel with your horse, you can flavor his water.
A week before departure, begin using a small amount of apple
juice to flavor the water at home. While on the road, repeat
the process, so he will be less likely to pick up the differences