I do the same thing Hugsplox does. My girl usually fasts during this time of the year (the colder months). Last she ate was October 20th. If she refuses a meal, I try again during her scheduled feeding the following week. If she refuses again, I then wait 2 weeks. If she refuses again, I then move to monthly. The only exception is, if during the fast she sheds, I try feeding like 2-3 days after the shed. And also try feeding if I notice she suddenly becomes very active at night, like she's "hunting".