I have hunted with Goldens for years and presently have two females. The eight year old is a sweetheart of a dog and a great bird dog. The other is two years old, has a great nose, retrieves fabulously, but has two speeds - fast and faster. She is a wonderful dog but is very hard headed and and aggressive, not to other dogs but everything else...she killed a skunk in our backyard last fall! I have tried everything I know of to slow her down. I have Dogtra collars on both dogs. The older dog occassionaly has to be vibrated once but that is all it takes. I can shock the younger dog on a high setting and she will be respond but will be back going 100 miles an hour immediately. With flushing dogs and an aging hunter, this is not good. Any suggestions from the pheasant hunters nation would be appreciated. Thanks, John