Endurance.Net Ridecamp Archives

Heidi,

I had a horse that was prone to thumping, but was one of those on which it
meant nothing.  He could be absolutely normal at every perimeter, but still
have that slight tic in his flank.  I controlled it with extra doses of
calcium.

In researching some of the reasons this particular horse was prone to
thumps, I came up with some interesting information.  One of the very well
known Endurance vets told me this horse had a large heart for his body size.
This was a very small horse, less than 13.3.  It seems to me since the nerve
in question runs near the heart and fires in rythym with it, that an extra
large heart in a smaller body cavity would be more likely to cause thumps as
the nerve would be positioned closer to the heart.  Is this false reasoning?

Another factor that I felt contributed was, this horse was raised in an area
where the grass is very high in calcium.  Cows pastured in the area often
develop milk fever in the spring due to the high level of calcium in the
soil.  I was given this information from a local large animal vet who
treated these cows so I assume it is accurate.  I know when a horse is given
an excess of calcium, his system loses the ability to source it from his
skeleton which I believe is what the normal horse does under stress. So it
stands to reason if a horse was raised in an area with an over abundance of
calcium available in the grass, his system is probably not well developed to
pull calcium from his bone.

I participated in a study conducted by Dr. Nagota back in the '80's.  He was
researching calcium levels and how they related to thumps.  At a 105 mile
ride in Ohio, blood was drawn from horses participating in the study 6
different times throughout the ride.  This particular horse finished that
ride in 3rd or 4th place so I was not riding conservatively.

After the ride was completed and all the data collected and reviewed, Dr.
Nagota called me as my horse was the only participant whose calcium levels
stayed stable or even elevated a little throughout the ride.  Since this was
inconsistent with the results from the other horses, he wanted to know why.
The answer, of course, was the extra calcium supplementation I was doing.
The only time this horse was ever pulled from a ride for thumps was at the
World Championships in Front Royal.  A Swedish rider had leased him and did
not follow my instructions on administering calcium during the ride.  The
horse was thumping slightly at 60 miles, but was absolutely normal in all
other perimeters.  Had we had another 15 minutes in the check, I could have
eliminated the thumps, but as I was unable to administer the extra calcium
until the check and he'd had none for 60 miles there wasn't enough time to
get the thumping under control.  Therefore, he was pulled.  The rider could
not have continued any way.  She was in far worse condition than the horse,
but the horse could have finished easily barring other unforseen events.

One other thing of note, at a convention where Valerie Kanavy was a guest
speaker. During her presentation, she talked about horses that recover to
extremely low  pulse rates, stating, that in her experience, these horses
often have issues in other areas.  One of the issues she mentioned being
thumps.  My horse had extremely good recoveries under extreme conditions.
He was often recovered to 32/36 BPM at a vet check very quickly.  I wonder
if the large heart may have contributed to the low recoveries and the
thumping as well.

Maybe this will shed a little more light on the issue of thumps.

Linda Courts


=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

Ridecamp is a service of Endurance Net, http://www.endurance.net.
Information, Policy, Disclaimer: http://www.endurance.net/Ridecamp
Subscribe/Unsubscribe http://www.endurance.net/ridecamp/logon.asp

Ride Long and Ride Safe!!

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=