Dirty ears? Ours carry tons of mud around in theirs!

I've occasionally used ordinary baby oil, never bought real pig oil. But generally they don't have moist skin anyway (nothing like ours, I mean), they always love having a scratch and it's quite normal to see flaky bits along their back. If they're not constantly scratching, it's probably ok.
I'm hoping to get my hands on one of those roller things like from a car wash, only smaller - 24/7 self service scratching! If I can get a waterhose connected to it, it'll be the first ever Pig-O-Wash!

These brushes exist for cattle, so why not for pigs, hey?

Eve
