Easily ignored Katrina
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Anyway...wherever the dogs drives lie....be it prey or food, the best method is the method that works for the DOG.
Some methods may produce behavior a little hectic in the beginning; but a skilled trainer can apply the proper amount of motivation/compulsion to clean the dog up and post some excellent scores!
I really think the dog tells you what method works best. I always try to encourage them to work for food however. I think it gives the handler a bit more control over the timing of reward...and keeps the dog from dislocating your shoulder trying to get the tennis ball
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