The stimulation, when done correctly, has far reaching positive effects on your pups but must be done according to directions. I learned about these methods from working dog competitors this summer. Please read the following 2 articles.
http://www.angelfire.com/ca/curlycr/2001pups2a.html
http://www.breedingbetterdogs.com/articles/early_neurological_stimulation_en.php
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