Question

I will be doing a combined driving event in a few weeks. I drive an athletic, good-moving 16-year-old American Saddlebred. He had an episode of laminitis a year ago presumably caused by vaccines but possibly caused by rich hay. I want him to have more energy but not be out of control. He currently gets 6-8 lb (2.7-3.6 kg) of senior feed, timothy/alfalfa hay, and about 8 hours of grazing on grass. What can I do?

Answer

I am sorry to hear about the laminitis, but it sounds like your horse has bounced back quite well.  It is a long, slow process to grow out the damaged hoof wall, but after one year he should be fully recovered.  Laminitis can be acute (a one-time occurrence caused by something specific like retained placenta, fever, etc.) or chronic (the horse is constantly or seasonally in danger of recurrence).

Chronic laminitis has been associated with equine metabolic syndrome and Cushing’s disease. Insulin resistance is a common factor in chronic laminitis and can be diagnosed with blood tests. Two ways to combat insulin resistance are to keep the horse at a healthy weight and to exercise him almost daily. From your description, it seems your horse suffered an acute case of laminitis rather than chronic. However, I understand your caution in trying to avoid it from happening again by keeping him on a feeding program that will not provoke insulin resistance. The amount of exercise he is getting in training for the marathon should help tremendously with this as well.

Your gelding is getting a low-energy diet for the amount of work he is doing. Senior feeds are designed to supply a portion of forage to the horse, which is what makes them fairly safe for horses with potential metabolic problems. However, they often don’t supply enough calories for the hard-working horse.

If you are concerned with the horse having more energy for work and staying power in a marathon, he may need a higher energy feed with more starch or fat. One of the simplest and safest additions to the diet would be oil (preferably ¼ to 1 cup canola or soybean) to increase the caloric density without increasing starch.  This may give the horse a little more staying power in the work but may not help with building muscle glycogen stores needed for energy generation.

Starch is the key to building muscle glycogen. Strategies to consider that take the need for starch and fat into consideration would be to exchange a portion of the senior feed with a higher energy feed (look for something with at least 8% fat and substitute 2-3 lb of the senior), or add a supplement like rice bran (20% fat; ½ to 1 lb per day).

I don’t think it would be necessary to completely replace the senior feed, and I feel like it would be adequate to swap out some of the senior for a higher energy feed.  All of the suggested strategies should be safe for a horse with a questionable history of laminitis as long as he is in training and competition.