How much to feed?

Well it looks like my female ball is building follicles now. I have been feeding her a small rat once a week. Should I feed her more often? She is 4 ft long and about 6 inches in girth. Sorry I dan't have scale to weigh her with. In the past she has eaten medium rats. Perhaps try 2 small rats per week?This is a pic of her with my husbands size 12 shoe for reference of size.http://ball-pythons.net/gallery/file...3/100_1686.jpgThanks for the help.

I would try a medium once a week or a small every 5 days! My girl are pounding back mediums right now but usually only eat small once a week. They need more fat to give them the energy it takes to build follicles!