You can try the old "stuffed and frozen kong toy." I ususally use a mash made from Bane's dog food (watered down) along with apple, carrots, broken down hard biscuits, and bits of roll dog food. I make 5 at a time and freeze them in heavy duty zip-lock freezer bags. He gets 1 a day. Other times I use an interactive rubber ball... Everlasting Fun Ball,
Everlasting Fun Ball
I fill it up with Old Mother Hubbard Meaties Treats (usually liver) and let him have at it, lol.
I also give him moozles,
Merrick Pet Foods - Dog Treats
or Bully sticks.
Hope this helps, lol.
VB