The Collaborative International Dictionary of English v.0.48:

Sallenders \Sal"len*ders\, n. pl. [F. solandres, solandre.]
   (Far.)
   An eruption on the hind leg of a horse. [Written also
   sellanders, and sellenders.]
   [1913 Webster]

         On the inside of the hock, or a little below it, as
         well as at the bend of the knee, there is occasionally
         a scurfy eruption called "mallenders" in the fore leg,
         and "sallenders" in the hind leg.        --Youatt.
   [1913 Webster]