Bizzare dog behavior

[HollywoodNVegas]

There is no real logical explanation, or so it seems from the description you offered, of why she no longer eats one of the shapes. Maybe a bad experience, who knows! Watch her and make sure this does not progress.

[Alysser]

That's very strange! Mabye, she just got tired of it after all these years? Mabye they changed the flavor to one she hates? Check the box and make sure she eats something!