I always start em at 7 weeks with a rolled up sock. Then progress to a paint roller, then finally to a canvas puppy bumper. Never really a plastic dummy till about 4 months of age. Start from the beginning.
It would help if you would tell us what you have done up til this point. If you have given the pup a lot of birds that may be your problem. If you bought a well bred dog, it would have the retrieving instinct from it momma. Its your job to enhance it. Let us know exactly what you have done with the dog.
are you trying to follow any type of training program?
Well I have a 15 week old black lap pup. My last lab would kill herself over a training bumper but this one couldn't care any less. Any ideas? This is a problem!! I work with her almost twice a day. Its so frustrating.
Let the pup be a pup. Socialize her, let her play, take her everywhere. If the breeding is good you will not have any problems.
Around 5-6 months they loose there baby teeth and may want nothing to do with retreives.
Wolters stuff is ok but rather outdated. I would recommend Hillmans latest stuff, it's expensive but many people are having great success with it
Steve
you have a link for Hillmans?