The 2 are completely different I feel like you may be describing
something slightly less serious then the other. Is his bum hole uhm
inside out like this?
<http://www.google.com/search?tbm=isch&hl=en&gl=us&q=prolapsed%20ferret%20rectum>

If so I found by making a sugar paste it works immediately. (add
water to sugar and mix to a paste consistency.) Here's my source
http://www.skunkhaven.net/Prolapse.htm

[Posted in FML 7286]