http://www.smartgroups.com/message/readmessage.cfm? gid=1423922&messageid=8096&startid=8098 Sevo is slightly better than Iso. It smells better, so the ferrets do not struggle as much when you mask them down. They also wake up faster from Sevo, and you can change the depth of anesthesia faster with Sevo. The only bad thing about Sevo is its high price. Also with Sevo they do not recommend atropine as a pre-med. Hope that helps, Jerry Murray, DVM [Posted in FML issue 4440]