Wouldn’t it be great if horses just slipped out of their winter coat like a snake shedding its skin? Unfortunately, at best it’s not even close but there are factors that can slow it down which you should be aware of.
There are some health conditions associated with delayed shedding including parasitism, pituitary pars intermedia dysfunction (Cushing’s) and an underfunctioning thyroid. Definitely get diagnostics done if the horse has any other indicators he may be suffering from one of these.
Exercise is your friend. It increases blood flow to the skin as well as production of sweat and sebum which help shepherd out those old hairs. Turning the horse out in an area where he can get a good roll will also reduce the level of sheer labor you have to put into getting rid of that hair.
If you find the horse starting to lag behind in shedding and the coat turning a burnt orange color, especially if there are also issues with dry, flaking skin, consider nutritional support. Several key nutrients for skin and coat health have been identified.
Hay begins to lose vitamin A activity 6 months after baling. By 1 year it is often too low to meet requirements. This typically coincides with late winter/early spring, before the grass has come in well or that year’s hay has been baled. The more faded from bright green the hay has become, the more A loss there has been. Target supplementation until the horse goes on pasture or that year’s hay is available is 20,000 to 40,000 IU/day. If the horse is not already getting this much from supplements or grains, add it separately.
The amount of fat a horse requires in the diet to support life is considerably less than what will give you optimal skin and coat health. A shiny smooth coat, supple moist skin and good local immune defenses result from supplementation of as little as 4 to 6 oz/day.
Biotin is also extremely important for skin health and skin cell division. Dry, flaking skin can signal suboptimal biotin intake. No specific daily requirement has been established but research into the effects of biotin on hoof quality have repeatedly demonstrated an intake of 20 to 30 mg/day provides best results. [Note: The hoof wall, sole and frog are specialized forms of skin.]
Finally, inadequate intake of protein in general or specific amino acids will adversely affect hair growth. If your hay is of poor quality or a very late growth stage cutting you may need more protein from high quality sources like soy and whey. Otherwise it may only be lysine and methionine you need to supplement. Give 10 g/day of lysine and 5 of methionine.
Whether you have a horse hanging onto a horrible looking old coat or you just want to support skin and coat to make the process as smooth and quick as possible, plugging the nutritional gaps in your horse’s hay should do the trick.
Eleanor Kellon, VMD