Ohhhh if she is as big around as a softball, a large rat is a tic tac lol. Caesar is as thick as a coke can and he easily eats 2XL guinea pigs and even those leave a noticeable lump but nothing him or i see as big as he still cruises around after eating one. You want to feed it something at least as thick as itself or up to 1.5 times as thick. I mean you can go bigger. I had fed Caesar stuff that made him look like he ate a football. Those were the only times when you could clearly see he was full and he waddled off behind a hide lol.