Teaching Gromit to obey commands and showing him that you're in control are part of raising a well-behaved dog. Part of this training should include getting him to release toys when told to. Use games, such as tug-of-war, as teaching opportunities to show your dog that you're in charge. In addition to spending quality time with your pet companion, he'll release pent-up energy and satisfy his urge to tug. With consistency, you can control your dog and his jaw with a simple command.
Arm yourself with dog treats and start a game of tug with Gromit. Take a tug toy from its designated storage spot and tease him with it. Dangle it in front of his face and say "take it" or "tug" to encourage him to grab it in his mouth. Get into the game and praise him for tugging.
Stop pulling the toy when you want him to release it. Hold Gromit's favorite treat in front of his nose and say "drop it" or "out." To eat the treat, your furry friend will let go of the toy. Praise him and give him the treat while you hide the tug toy behind your back.
Instigate another game of tug and repeat this reward-based obedience training each time you play tug. Always use the same commands so Gromit knows what they mean.
Gradually reduce the number of times you give your pet companion a treat for releasing the toy. Use verbal praise instead, and start a new game of tug as a reward for obeying.