Drought stress and laminitis go hand in hoof
This year (2011) has been a record setter for the mid-west. Here in
Kansas we went from a mild fall to a bitter, cold winter then immediately to a hot, dry summer. I think as I write this, it
has been over 100 degrees for 42 days this summer, and we are just entering August! All this drought has dried up pastures
and hay fields and while many think "there's nothing out there anyway" and turn their horses out, I'm seeing a spike
in laminitis cases. Keep in mind that your cool season grasses like Brome, Fescue and Orchard grass are struggling in this
heat. With stress come more NSC (grass sugars).
The grass is always producing sugars when the sun shines, storing it up for use in growth at night. The grass is not growing
due to less rain, so the sugar is just being stock-piled and the grass, while short and brown, the grass is extra sweet and
dangerous for horses that are prone to laminitis! Also, as the drought continues, the grass contains more nitrates which will
stress the digestive system of the horse as well. Both of these negatives will be present in whatever hay is cut during this
intense heat! What you may find, is a need to soak your hay to dilute the sugars. Or, feed more native prairie grasses which
contain less sugar and are better rounded nutritionally anyways since it contains many plants. (Remember only eating one food
is not nutritionally complete like eating only steak every day and no salads). Once we get a good rain, the grass will be
less concentrated. It's a myth that the lush wet grass is what triggers the laminitis-it's the sugars that often spike with
cool nights and warm, sunny days in the spring instead of the rain. In fact, the taller the grass, the less concentrated the
sugar. The warmer the weather, the more diluted. The more rain, the more diluted.
Mowing, overgrazing, drought, cold snaps with sunny days and cool season grasses are the dangerous
sugar increasers. Tall, native warm-season grass during the mid-summer with regular rain is your lowest risk. (Keeping in
mind that a grain-fed horse is always higher risk than a hay-only fed horse for laminitis as well as sudden diet changes).
Watch your turnout. If you have an IR horse, save turnout for dusk-morning
to avoid some of the sugars. Or, just dry lot your horse. I don't recommend grazing muzzles when temps top out above 100 degrees.
Horses are suffering from heat stress the muzzle adds to the heat and the metal on the muzzle could burn the face-I've seen
a few that have blistered from the metal on halters (which I don't condone leaving halters on in the pasture anyway). When
the temps drop back to normal 80's-90's the muzzles are fine to go back on.
My feeding regime this summer has been night turnout (as usual for mine) for the horses
with no metabolic issues, and dry lot for my at-risk horses, and feeding more alfalfa pellets, bran mashes and prarie
hay, with their supplements. I have found they aren't eating as much in the heat, but standing in front of the fans in
the barn. No grain, especially since I'm riding a lot less in the heat.
When the fall comes, you need to watch the grass again. Cold, frosty nights and bright sunny days will also
produce excess sugars in the grass and increase laminitis risk if you aren't careful, again, the risk is always higher with
cool-season type grasses.