i enjoy collecting rare taming quest animals. The last two mad cows I have found have been guard whacked. Any ideas on how to prevent this? Better question, is there a way to tame them in town?
Attack it. If you attack it before it attacks you, then it will not get guard whacked for defending itself.
Once you have it tamed, make sure you don't say 'all guard me'. No, I've never done this to myself, why do you ask?