Hi, try these links.....
http://www.iwt.co.uk/
http://www.houghtons.com/
http://www.tfmengineering.co.uk/livestockcanopy.html
What a bizarre question!!!!!
Best way is to let them walk though they can run, hobble and sometimes swim!
In an emergency i've had ones in boot of car, on rack of quad bike and even in the loader bucket though it might have been dead!!