Horses Sweat Detergent and Other Scent Secrets
Perspiration in the animal kingdom is often not just a simple sweat and stink process, as new research demonstrates. Horse sweat, for example, turns out to contain a natural detergent, appropriately named latherin, which does indeed lather and function like soap.
Malcolm Kennedy of the University of Glasgow and colleagues report in the latest Journal of the Royal Society Interface that latherin probably evolved, first as a protein ingredient in saliva to help process dry fibrous foods, and then later was "recruited to the skin as equids evolved into large-bodied flight animals capable of sustained exercise requiring rapid onset and efficient heat dissipation." Latherin, among other functions, "facilitates spreading of the sweat over the oily pelt of the horse."
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