Here is another VERY INTERESTING article to read. I don't know when it was written but check out the picyure of the brooder and what they are using for a heat source.:cd Mark, check out chapter 4 on pigs.
Jimmy
http://www.fao.org/docrep/t0690e/t0690e08.htm
There is some great FAO manuals out there. They are normally written for third work countries and farmers that have limited resources so the kerosene lamps fit the target.
They are great beginner tools