On the inside of the hind legs of all white-tailed deer are glands called tarsal glands. They consist of a tuft of long hairs coming from an area of skin in which are located glands that secrete a fatty substance. This fatty substance adheres to the long hairs. When deer urinate, they often assume a crouched posture, causing their urine to run over these hairs. The lipid, or fatty material, on the hairs causes some of the urine that runs over them to remain there. Excess urine is licked off by the deer. The combination of fatty material and urine gives the glands a unique smell (not the typical deer urine smell.) During the breeding season mature bucks urinate on the tarsal gland much more frequently, and don’t lick off the excess urine, which creates a distinctive rutting odor . This practice is referred to as “rub-urination.” All deer urinate on these glands throughout the year.