So sometimes I have to feed my inner geek by watching the MythBusters on the Discovery Channel. Recently they had an episode where they covered a surface with animal birthing lube. It looked really slick. Here's a link where you can order it:
I just called a local farm supply store and, after convincing them that I wasn't going to be using it to fist my dog, they are going to order it in for me. They aren't charging me shipping, so it will cost me between $10 and $15 for a gallon. I am sure you would want to dilute it so it will last awhile. I'll post the results when I try it out.