With an adult? Never, it can take time, it can take tweaking the husbandry, but last thing you really want to do is offer an alternative type of prey unless you are willing to do so long term and some are just not advisable.When do you start to panic about your BP not eating?
It's really about patience and understanding that they are very efficient, I had animal half that size fasting for 6 months and animal that size fasting for a year.