Okay so she does eat mice just won't take a second one and refuses rats...gotcha. Could you describe how you offer the second f/t mouse (method, etc.). If she's taking jumbo mice she may be quite fine with one per week and they don't have to have a significant bulge to be wellfed. None of mine from the smallest of the babies to the biggest of the breeder females looks more than slightly thick after eating but no visible lumps or belly bulging after they eat.