Anyone who's ever owned a cat knows how fast cats can run at the sound of a can opener or pop top. It's a conditioned response - they know that sound means food. Even if you're opening your own can of soup - they come running.

On the vet's advice, I stopped feeding my cats wet food about 5 years ago. So, they started responding to the rattling of the bag of kibble. But my cats are getting older and my oldest cat was getting very skinny. It was worrying me because he'd always been a big cat. The vet said his heath was good for an almost 16 year old cat. But he'd always been about 17 lbs and he was down to 8.

So, I recently started feeding them wet food again. The very first time I opened that can of cat food, they came running. I was amazed that they're still conditioned to that sound 5 years later!