That is part of the harness for his saddle. Kitara, as a Dragon Highlord, rides him into battle.
I've always been a big fan of Elmore, and think his classic work holds its own against the best of today's (I agree it is a matter of taste). This picture is deliberately posed, which I normally don't care for, but it matches the style of the original book covers (See examples
here, here, and
here) so it doesn't bother me as much.
Having said that, this is not a favorite for me. Skie looks particularly emaciated and sickly, though I realize it was probably necessary to shrink him down to get him to "fit" in the frame (again, similar to the original artwork linked above), but this does look particularly glaring. I mean, he looks like a slightly oversized antelope that Kitara is thinking about riding.