Wednesday, April 12, 2017

When it Comes to Spring Green Grasses…Less is More!

Aahhh, spring!  Goodbye to cold and hello to flowers blooming, trees coming back to life and green, thick, lush grass in our pastures.  It's so satisfying to watch our horses merrily munching away.  But lurking in those waving fields of green are some serious threats to your horse’s health. 

Sugars, Starches and Fructans, OH MY!  These non-structural carbohydrates can create significant health problems in certain horses.  Coming off low-quality winter pastures or a diet of hay, the lush green spring grass can shock a horse's system and result in any one of the following conditions:

When horses graze, their digestive enzymes break down the grass into glucose, which is readily absorbed by the body.  But, if blood glucose levels become too high, the laminae in the hooves can soften and detach.  This allows the Coffin bone to sink and results in laminitis, a painful condition that, if not caught early, can cause permanent damage.

Insulin Resistance 
When cells become less sensitive to the action of insulin, which controls sugar levels in the body, cells can store too much glucose.  A diet high in non-structural carbohydrates, as is found in new spring grass, can contribute to this condition.  Abnormal fat deposits (e.g. above the eyes), excessive drinking and urinating, and laminitis are all symptoms of insulin resistance.

Nasopharyngeal Cicatrix Syndrome (NCS)
Often referred to as simply “Cicatrix”, this condition involves the pharynx, which becomes inflamed and irritated.  Over time, the inflammation can lead to scarring that narrows and constricts the airway to a degree that sometimes requires a permanent tracheostomy to allow the horse to breathe.  While fresh spring grass isn’t the direct cause, the fungus, mold and pollen hiding within it can cause the irritation that leads to the condition.

Grass Glands
Have you ever brought you horse in from the field and found large, firm and usually painless swellings in the area where the throatlatch would rest?  It’s enough to freak out the unprepared owner!  These lumps, which may even be accompanied by fluid under the skin, are often mistaken for a symptom of the Strangles virus.  

But, fear not!  They are simply swellings of the parotid salivary glands and they will retreat on their own, causing no discomfort to your horse.   

There are ways you can help your horse avoid these complications of grazing in new spring forage. 

  1. Graze at night.  Photosynthesis triggers the sugar in grass, so the peak accumulation of sugar is between 3-8pm.  The lowest amount of sugar is between 9pm and 8am, so grazing during these hours will be safest.  
  2. Limit grazing time.  If you don't want to keep these kinds of hours (yawn!), then limit grazing to 1 hour a day for 3-4 days, then increasing in 30 minute increments with each cycle.  Max time out for a horse with issues would be 4-6 hours.
  3. Reduce his intake.  Muzzles can cut forage intake in half, while still allowing your horse to hang out with his friends and enjoy the new grass.
  4. Exercise.  Daily exercise will work off the sugars your horse has ingested, off-setting the potential harmful effects.
But, if your horse has no health issues and green grass doesn't seem to bother him, then grazing 24 hours a day has actually been shown to REDUCE insulin peaks due to decreased consumption of grass.  Horses allowed to graze constantly will actually stop when they feel full, while those kept in a dry lot and let out to graze tend to gorge uncontrollably.

Of course, here in Texas, that lush spring green grass won’t last forever!  Enjoy it while you…and your horse…can!