First make sure the dumbbell is fitted correctly. An ill fitting dumbbell may cause the dog to roll it more than necessary.
You may want to consider a plastic dumbbell. Riven did much better with a plastic one, it was heavier and he focused on holding it more than the wooden one.
Teaching the hold is the most critical part of the whole retrieve exercise. You need to start with giving the dog the dumbbell and only allowing them to hold it for 1 second (the time is critical it MUST be only one second). Use your marker word (yes!) and have your hand just beside the bell to take it back the minute you use your reward word, follow up with lots of yummy treats. Don't allow your dog the time to roll it in his mouth.
You start with a one second hold and gradually up the time slowly as your dog is successfully holding it without rolling it. If necessary I use a finger just under the jaw to GENTLY hold the dogs chin up slightly. This can sometimes reduce rolling. However you still need to work on very gradually increasing the time you ask for the hold.
If your dog begins to roll the dumbbell I would use a NRM (oops!) and start over. Be patient and build time up slowly. It helps to have the dog sitting and their head tilted up slightly while doing the hold.
Good Luck!
Dawn
U-CD Cammcastle's Mystic Riven CDX OAC OJC OGC NA NAJ TT CGC
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