Holstein horn? The scrimshaw folks really like those white horns.
I've sanded a few buffalo horns, and know the pain you went through with sanding them from the rough. But they sure do look purdy once they are all shined up.
If they stink real bad, then you probably want to seal them. The inside of the horn tends to get nasty from the moisture of one's breath blowing on them, and when the moisture hits the raw horn, it doesn't smell the greatest over time.
Brian