Dr. Lydia Gray Of SmartPak Answers Your Questions: Changing Your Horse’s Diet from Growth to Maintenance

[originally published in the March 2016 issue of Show Horse Today]

How long should a horse be on a growth type feed? I have a 2-year-old QH filly, and she’s in training full time now, going to be a reiner. I’m bringing her home in a few weeks to give her a rest, and I need to purchase some grain for her.  My other horse is on Senior, and I don’t think she needs that! So, my question is, how long should a horse with no health problems be on a growth type grain? Is there a magic age, or does it all just depend on the horse?  – AO, Indiana

 

Dear AO,

I wish there were some magic in caring for horses! My go-to source for all things equine nutrition is the sixth edition of Nutrient Requirements of Horses, published by the National Research Council or NRC in 2007. Considered the “bible” for feeding horses, it provides daily nutrient requirement charts for energy protein, vitamins and minerals for all life stages of horses: adult, working, stallions, pregnant mares, lactating mares and growing animals. Growth as a life stage is further broken out by these ages/workloads:

4 months


6 months


12 months


18 months


18 months light exercise


18 months moderate exercise


24 months


24 months light exercise


24 months moderate exercise


24 months heavy exercise


24 months very heavy exercise

At two years of age, or 24 months, the NRC still considers horses to be growing, meaning certain nutrients are still required in higher amounts. For example, let’s say your two-year-old fits in the heavy exercise category. According to the chart for Mature Body Weight of 1100lbs, she would need 27.9 Mcals of energy, 969 grams of protein and 41.7 grams of Calcium. An adult horse with the same workload would only need 26.6 Mcals of energy, 862 grams of protein and 40 grams of Calcium. So you can see that your horse still requires a growth diet.

My advice is to purchase the same kind of grain she was on at the trainer’s (provided it was a growth diet) so you don’t have to make a feed change in addition to a barn change. Then over the next six months to a year, gradually transition her to an adult horse feed, carefully monitoring her weight to make sure the amount of calories she’s getting is maintaining her at an ideal weight. If you find yourself having to back off the grain to keep her from getting too heavy, considering switching to a ration balancer or multi-vitamin/mineral supplement. On the other hand, if she’s having difficulty maintaining her weight with her heavy workload, think about switching to a grain with a more concentrated source of calories or adding fat to her diet.

Feeding horses always comes down to making sure you’re meeting their protein, vitamin and mineral needs while not over or undersupplying calories. Sometimes commercial grains meet horses’ needs and sometimes they don’t. Talk to your veterinarian or local nutritionist for advice on the best time to transition her from growth to maintenance, and for their opinions on her weight and what product might best meet her nutritional needs (grain, ration balancer, multi-vitamin). I wish you and your filly much success!