California Riding Magazine • November, 2011

Questions for Dr. Lydia F. Gray

by Lydia F. Gray, DVM, MA

What is the real answer to sweet feeds?  Does it make horses "hot"?  My 3 year olds have been on Omelene 200 and switched to Omelene 100.  I recently discovered it has a NSC of 40%.  Sounds really high to me.  I can't switch to pellets because my mare has choked three times on it.  I tried making it into a mash, but she won't eat it that way.  I did notice they seemed calmer on Purina strategy Healthy Edge which has an NSC of 18%.  But, since my mare choked on it and she won't eat it as a mash, I don't know what to feed next. Thanks for any help. Carolyn

Dear Carolyn,

Before I touch on sweet feeds, I want to give you some advice about your mare that chokes, because that can be a serious issue, especially if she continues to do it. Choke in horses is when something gets stuck in the esophagus (like feed, bedding or a foreign object). This is different from choke in a person which involves something stuck in the trachea or airway but it can still be life-threatening because the horse can’t swallow anything. Choking is associated with horses that eat too fast, so suggestions typically include feeding small meals frequently, spreading grain out in a shallow trough, putting large fist-sized stones in the feed tub, adding chaff or some kind of short-chopped forage to the grain, etc. There’s even a new kind of feed tub specifically designed to slow grain eating in horses. Choke can also occur because the horse is not chewing properly so any horse that chokes should have its teeth and mouth examined. I encourage you to talk to your veterinarian about your mare’s choking and make sure you’re doing everything you can to prevent it from happening again.

Back to your original question! According to the NRC’s Nutrient Requirements of Horses:

“In studies examining the effect of dietary energy source on the clinical expression of recurrent exertional rhabdomyolysis [tying up] in Thoroughbreds, researchers have reported decreased excitability, nervousness, and resting heart rate when the horses were consuming a fat-supplemented ration when compared to a high-grain ration. These authors suggested that the effect of fat supplementation on the behavior of RER-affected horses was due to the exclusion of dietary starch rather than a specific effect of dietary fat.”

In other words, feeding concentrates with a high NSC percent can lead to horses being “hot” as you describe. While every horse responds differently to the various feedstuffs in the diet, I agree with you that the 18% sugars and starches found in the Healthy Edge version of Strategy--plus it’s higher 8% fat content—probably does provide a “cooler” form of energy and calories than either of the two Omolene sweet feed products.

But the “real answer” to sweet feeds depends on your real reason for feeding them. Do your horses need the full portion of fortified grain to add or maintain their weight?  Are they in moderate to heavy work (or pregnant or nursing) and have high requirements for energy and other nutrients? If not, you may be better off feeding a ration balancer or multi-vitamin/mineral supplement and avoiding the sugars and starches in fortified grains altogether. Each of the feeds you mention in your question must be fed at a rate of at least three pounds per day (some as high as nine pounds!) along with hay to obtain the minimum protein, fat, vitamins and minerals a 1000-pound horse in moderate work requires. Switching to a product like a ration balancer or multi-vitamin/mineral supplement which complete and balance the diet at a much lower feeding rate could benefit your horses both in terms of choking and “hot” behavior. I hope this information helps you select the most appropriate diet for your horses and that you are quickly able to resolve your mare’s choking issue.

Article provided by SmartPak.
Dr. Lydia Gray is the Medical Director/Staff Veterinarian for SmartPak, where she guides research and new product development, answers questions on her Ask the Vet blog, and speaks around the country at various events such as Equine Affaire, Dressage at Devon, and the USHJA Trainers’ Symposiums.