Q. My horse is starting to shed his winter coat, and I’m wondering whether there is anything I can do nutritionally to speed up the process and that will also ensure a good-quality summer coat?

A. While most of us look forward to the longer days and warmer weather of spring, shedding horses can leave the barn looking like a yak thanks to shedding winter coats. I don’t blame you for wanting it over as quickly as possible!

Some anecdotal reports suggest that feeding flax or black oil sunflower seeds can help horses shed out more quickly. This is likely due to the oil these feeds contain. However, I have found no scientific evidence to support this assertion. The best way to speed up the removal of old coat is rigorous grooming before and after exercise using a rubber curry comb or similar grooming tool. If the weather is warm enough, a bath will often help loosen hair. So will a good roll in a sandy arena.

Don’t be fooled into thinking that blanketing your horse will help them shed faster. Day length is what triggers hair loss, not body temperature.

Fat and Horse Hair Coat Quality

While feeding fat to speed up shedding might be no more than placebo effect, adding more fat to the diet might help improve the new coat’s quality. The hair shaft is coated in cuticle cells that contain a substantial amount of fat that helps retain moisture. These cells should lay flat, and when they’re flat they reflect light beautifully. However, if damaged, moisture is lost from the hair shaft, and the hair becomes dry and no longer reflects light with the same brilliance. Additionally, pores in the skin release sebum, which is an oily substance that coats the hair shaft and helps maintain shine. Diets that don’t provide adequate amounts of fatty acids could result in a dry hair coat that’s more susceptible to damage and a dull appearance.

Take caution before supplementing fat to ensure it is appropriate for the individual horse based on body condition. However, even relatively small amounts of fat should have a positive impact on coat quality. Try to use fat sources that provide essential omega fatty acids especially those that supply greater quantities of omega-3 than omega-6. Flax and camelina oil are good options, and you only need to feed about 2 to 4 ounces per day for an average-sized horse. If feeding flax seed, either whole or ground, feed about 4 to 6 ounces by weight, which is about 1 cup by volume.

Supplementing oil also supports supple, healthy skin and reduces dandruff and flakiness.

Vitamins

Vitamin A is a key nutrient that plays a role in skin health, and while the equine dietary deficiencies are rare, they can occur if you’re feeding older hay. While the precursor to vitamin A, beta-carotene, is abundant in fresh forages, it is lost from hay at a rate of almost 10% per month. Therefore, by late winter/early spring hay might have lost 50% of its beta-carotene, and by the time hay is a year old it’s likely horses will need an additional vitamin A source to meet their basic dietary requirements.

Protein and Amino Acids

The hair shaft is made up mostly of the protein keratin. Diets that provide inadequate protein or that lack essential amino acids could result in reduced hair growth. This, in turn, could slow down shedding. Look at the quality of the forage you’re feeding. Very stemmy hay, the result of cutting plants when they are mature, might need to be supplemented with feeds that provide quality protein, such as soybean meal.

Copper and Zinc’s Role

Ensuring horses’ dietary copper and zinc requirements are met will also help support coat color. Both these minerals impact melanin, the protein in hair that is responsible for pigmentation. If the hair contains inadequate amounts of melanin, it is unable to resist damage from ultraviolet light. This leads to oxidative damage and fading.
Copper is also needed by the enzyme lysyl oxidase, which is necessary for the maintenance of the cross-bridges in collagen within skin. Without adequate copper these cross linkages are weakened and the skin loses structural integrity.

Take-Home Message

A balanced diet with appropriate levels of protein, trace minerals, and vitamins supports healthy skin and coat. For greatest effect you should make sure that all dietary requirements are met before shedding starts. That way the new coat will be fully supported from the very beginning of its growth. Combine this with rigorous grooming sessions and you will have a fabulous summer coat before you know it.