Dandruff in a horse’s manes has many causes. If you find dandruff in your horse’s mane there are two ways to treat it: internally and externally.
To treat horse mane dandruff from the inside out you should examine your horses diet and feeding program. Make sure your horse is getting enough fat in their diet. Fat is essential to a horse’s healthy skin. If you find your horses diet may be lacking, there are many types of supplements you can add, from good old-fashioned corn oil to flax seeds and sunflower seeds, or a prepackaged pre-formulated dietary supplement such as Horse Tech’s "BioFlex 20". Supplying these essential fats will help keep your horse’s skin moist and improve or eliminate the horse dandruff in the mane.
You should also treat your horse’s mane dandruff from the outside in. Many times dandruff in the mane can be caused by fungus growing in the mane. So the first course of action should be to shampoo the horse’s mane
with an anti fungal shampoo. This type of shampoo can be found at any farm store or most tack shops. Shampoo thoroughly and rinse completely, leaving any residue of soap may irritate the skin further. After you have shampooed the horse’s dandruff out of the mane with anti-fungal shampoo you should consider applying a topical treatment regularly to the horse’s mane. One topical spray that will help eliminate mane dandruff is Muck Itch. Muck Itch will naturally kill fungus and soothe the skin, eventually helping the mane grow longer.
Some horse owners even swear by Vaseline, mineral oil, or petroleum jelly rubbed in to the base of the mane with persistent non-fungal dandruff that cannot be cleared up through nutrition. Be careful with topical oil-based treatments however, only apply in late afternoon or on cloudy days, as hot oil and as the sun can warm hot oil uncomfortably on the horses skin.
By treating your horse’s mane dandruff from the outside in and the inside out you should be able to reduce the appearance of dandruff with in 10 to 14 days. It is important to take care of dandruff as soon as you see it, as leaving dandruff unattended can make the horse’s mane itch and may cause the horse to rub their mane on a fence or trees, which will make their mane hair fall out. These tips should help you clear up your horse’s mane dandruff.