Feeding the HYPP Horse
Hyperkalemic Periodic Paralysis (HYPP) is an inherited genetic defect that affects muscle function in the horse. Symptoms can vary widely among horses, from mild muscle tremors to death from cardiac arrest or respiratory failure. A test is available to identify horses that carry the defective gene. HYPP horses are sensitive to high levels of potassium in their diets, as well as sudden changes in potassium levels that can be brought on by stress, pregnancy and activity.
Symptoms of Hyperkalemic Periodic Paralysis (HYPP)
HYPP is characterized by sporadic attacks of muscle tremors, weakness and/or collapse. Attacks can also be accompanied by loud breathing noises resulting from paralysis of the muscles of the upper airway. Here are a few symptoms to watch out for:
- Muscular fasciculations (tremors) down the rib cage and under the flank.
- Eversion (turning inside-out) of the third eyelid.
- Horse exhibiting signs of colic or “tying-up”.
- Elevated blood serum potassium levels, 3-4 milliequivalents per liter (mEq/L) is a normal serum potassium, but can be as high as 12 mEq/L with a severe episode.
- Tetany, paralysis and death in severe cases.
What to Feed the HYPP Horse?
Hay can have a much higher potassium level than commercial horse feeds or feedstuffs like oats. Feeding large amounts of a high fiber, low potassium feed like Triple Crown Low Starch, along with a limited amount of hay, allows for more control over the potassium level of the total diet. Grass hay usually contains a lower potassium level than alfalfa hay so only grass or mixed hay is recommended for HYPP horses. Feed the limited amount of hay twice per day and the horse feed three to four times daily, if possible. Here are some ways to safely feed horses that have been diagnosed or suspected of having HYPP by keeping dietary potassium levels low, less than 1.3%.
- For mature horses who are easy keepers, feed whole or crimped oats (0.4% potassium) and Triple Crown 30% Ration Balancer, the ration balancer helps to ensure the horse gets essential and balanced vitamins and minerals each day. Adjust the amount of oats fed to maintain proper body condition. Triple Crown Essential Omega Blend Oil can also be safely added to the feeding program if more calories are needed.
- For harder keepers, feed Triple Crown Low Starch (0.75% potassium) at a minimum of 6 lbs. per day, in addition to your normal amount of hay but you can also adjust the feed up and the hay portion down as the Low Starch is a high fiber pellet (18% max) and can be a forage substitute.
- If you have not tested your hay, or if the potassium level of your hay is 1.5% or more you may want to limit the amount of hay you are feeding to keep potassium levels low. (You can contact your local or state extension specialist about testing your hay for potassium content. A test for potassium and several other minerals and nutrients should cost less than $20.) Provide Triple Crown Low Starch (0.75% potassium), at 1% of body weight and feed only 0.5% of body weight of hay per day. This would be 10 pounds of feed and 5 pounds of hay for a 1,000-pound horse on a daily basis, which is the minimum amount of feed that should be provided for an inactive horse. For a more active horse, increase the amount of feed but not the amount of hay to keep the total dietary potassium level as low as possible.
Triple Crown is committed to providing the best nutrition for every horse. That’s why we provide a variety of super premium feed and forage options to fit any horse’s unique diet. If you have any dietary or feed questions, please contact us today. We’d love to help!