Hoof Nutrition Intelligence is a twice-a-month web segment that is designed to add to the education of footcare professionals when it comes to effectively feeding the hoof. The goal of this web-exclusive feature is to zero in on specific areas of hoof nutrition and avoid broad-based articles that simply look at the overall equine feeding situation.
Below you will find Part 1 of the latest question and answer installment that you can share with your footcare clients.
Q: Can feeding biotin help eliminate rainrot concerns with one of my horses?
By Laura Petroski, B.V.M.S., and Catherine Whitehouse, M.S.
Wet conditions and opportunistic bacteria combine to produce rainrot, also known as rain scald, which is a skin infection that can wreak mayhem on a horse’s coat.
Once thought to be a sign of neglect, especially inadequate grooming, rainrot is caused by a specific pathogen that takes advantage of a compromise in skin integrity, such as an abrasion. Horses chronically affected with rainrot harbor the bacteria Dermatophilus congolensis.
When lesions become moist, bacteria release zoospores, the infective stage of the bacteria, which are easily transmitted from one horse to another through flies. Because healthy skin is a resilient barrier, a compromise must occur for the bacteria to take hold. Any break in the skin or unchecked moisture can allow an infection to become established.
Characterized by grayish-white scabs, rainrot seems especially prevalent among horses with an inadequate immune system, such as those that are old, stressed, undernourished or beset with endocrine problems such as Cushing’s disease.
Coupled with management changes, such as keeping horses dry and regularly groomed, mild cases of rainrot can usually be cleared up through the use of shampoos and topical treatments that are labeled specifically for use against rainrot. If these topical treatments do not work, a veterinary examination is warranted, as there may be an underlying health concern.
From a nutritional perspective, recurring bouts of rainrot can be a sign of imbalanced nutrition. The power of a well-fortified diet is occasionally underestimated. When fed well, horses have an incredible ability to fend off attacks by everyday pathogens, including those that cause skin disease.
Nutritional supplements can provide further protection for horses susceptible to rainrot. While the advantages of biotin on hoof health are well documented, biotin is also beneficial to the skin and coat, especially when mixed with other important nutrients. In addition to biotin, methionine, iodine, zinc and essential fatty acids support coat health.
Because many horses with rainrot have immunity issues, bolstering a horse’s ability to fight off infection can ward off skin conditions. The long-chain fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), are known to strengthen immune function. These fatty acids are derived from marine sources, which are superior to plant-derived fatty acids.
Laura Petroski is an equine veterinarian and Catherine Whitehouse is a nutrition advisor with Kentucky Equine Research. The Versailles, Ky., based firm is an international research, consulting and product development company working in the areas of equine nutrition and sports nutrition.
Hoof Nutrition Intelligence is brought to you by W.F. Young Co. (Absorbine). 
Like many significant achievements, Absorbine® grew out of humble beginnings—and through the tenacity of someone willing to question the status quo. In this case, it was a young woman in late 19th-century Massachusetts: Mary Ida Young. Her husband, Wilbur Fenelon Young, was an enterprising piano deliveryman who relied on the couple’s team of horses to make deliveries throughout the Northeast. Inspired by Mary Ida and Wilbur’s vision, Absorbine® has continued to add innovative products throughout the years — products used every day by horse owners around the world. Which is why, since 1892, we’ve been The Horse World’s Most Trusted Name®.
Click here to read Part 2 of the Oct. 1, 2018 installment: Do I need to be concerned with laminitis during the fall months?
Click here to read more installments of Hoof Nutrition Intelligence.