Management of insulin resistance with supplements

Insulin resistance (this is now the preferred term over "metabolic syndrome") is related to multiple health issues in horses, particularly an increased incidence of laminitis. Several supplements on the market are marketed to help control insulin resistance in horses with magnesium and chromium. This study, done at New Bolton Center and University of Tennessee College of Veterinary Medicine, indicates that these do not have a measurable effect on affected horses and ponies.

Effects of a supplement containing chromium and magnesium on morphometric measurements, resting glucose, insulin concentrations and insulin sensitivity in laminitic obese horses

1. K. A. CHAMEROY,
2. N. FRANK*,
3. S. B. ELLIOTT,
4. R. C. BOSTON

Article first published online: 29 SEP 2010

DOI: 10.1111/j.2042-3306.2010.00302.x

© 2010 EVJ Ltd

results and conclusion:

Results: Hyperinsulinaemia (>30 µu/ml) was detected in 12 of 14 horses prior to treatment. Glucose and insulin data from one mare with clinical laminitis were excluded because of persistent pain. Mean ± s.d. insulin sensitivity was 0.64 ± 0.62 × 10−4 l/min/mu prior to treatment for the remaining 13 horses. Time and treatment × time effects were not significant for any of the variables examined, with the exception of resting insulin concentrations, which significantly increased over time (P = 0.018). Health status remained the same.

Conclusions: The supplement containing chromium and magnesium evaluated in this study did not alter morphometric measurements, blood variables, resting insulin concentrations or insulin sensitivity in laminitic obese horses.

Unfortunately weight loss through diet and exercise is the only proven disease modifier. We all like to please our horses and enjoy seeing them enjoy their food but any horse will lose weight if the calorie intake is reduced enough. Total starvation is a very bad idea and will cause other problems, particularly in obese horses.

Weight Management

If you are trying get your horse to gain or lose weight, knowing the actual amount in weight of hay and grain you are feeding is important. Once this is determined your veterinarian can help guide you in determining the optimum amount to feed your particular horse. A scoop or can is not a measure of grain that means anything. A flake is not a measure of hay that means anything. The only valid measurement is weight. Different feeds will weight different amounts for the same volume. You do not have to weigh every feeding, but weighing the volume measure that you are using will give an accurate result as long as you do not change feed. The average bale of hay weighs from 35lbs to 60 lbs. Either weigh a bale and figure how much a 6 inch flake weighs as a fraction of the bale or weigh your average flake. Round bales in the field count too! You can't measure them, but figure that a horse will eat 25-30 lbs a day free choice. That will be greatly reduced if the round bale is nasty or moldy. Most horses get too much grain and not enough hay, but there are some easy keepers that will not lose weight given free choice hay and no grain. Total hay needs to be reduced to about 15 lbs a day with no grain (for an 1100 lb horse) to make a dent in their weight.

A fisherman's scale should cost $6-$10 and is accurate enough (if you want to splurge, get a digital one for about $20)

To track your horses progress, use a weight tape (usually free at the feed store) They are not perfectly accurate for absolute weight, but they are very accurate in tracking gain or loss. If the number is going up or staying the same and your goal is to reduce weight, the horse is eating too much or not exercising enough or both!