[pigsforlife]

I find it hard to imagine how you can be allergic to the odor of their urine. You are either allergic to the PROTEINS in the urine or saliva or the pigs hay. What is the difference between leaving your dog outside and your pigs? Pigs should be treated equally, like a family member and therefore your answer is simple. BRING THEM INSIDE! If you have a problem with smell, CLEAN IT MORE OFTEN! Pigs are fragile little critters that are not only good targets for predators (like your neighbours cat) but also can not cope with the (often drastic) temprature changes.