Some horses do tend to have their own shedding schedules. Shedding later than others may be due to the color of the horse's hair coat, amount of daylight they receive, parasitic level and overall health. Lack of shedding may be a sign that your horse is having thyroid problems. Talk to your veterinarian about doing blood work on your horse, checking T3 and T4 levels. This might either answer this unsolved mystery or at least eliminate thyroid imbalance as a factor. But before you conduct thyroid level testing, please consider the following:

1. A regular worming schedule would be the first recommendation. It may be beneficial to rotate worming products and methods. Consult your veterinarian on the types of medications and the most effective rotational program for paste versus tube worming methods.

2. Body clipping your horse late in the year to keep that short hair coat can also throw it off the growing/shedding schedule. Horses that are body clipped in the winter will tend to have a longer hair coat into the summer months. It is not recommended to body clip unless it is absolutely necessary.

3. The amount of daylight is also a key factor in hair loss. Horses retain their hair coat when the days (daylight) are shorter. So, if you extend the amount of daylight to 16 hours a day by using artificial light, you will mimic a longer summer day to induce shedding or even estrous activity in mares. Artificial light in the horse's stall should be bright enough to read a newspaper in the darkest corner of the stall. You can use an automatic timer to trigger the lights to turn on and go off.

4. The old-fashioned way to get them slick is a lot of elbow grease. First groom your horse with a soft rubber curry comb in small circular motions to release the hair and dirt from the horse's hide. Then brush all loose hair and debris from your horse by first using a harder brush and then going to a softer brush. Several brushing sessions a day will achieve maximum results.

5. Avoid hosing your horse down with cold water if the weather is cool and your horse is hot and sweaty. Hosing a hot horse down in cool weather may promote hair growth.