Gulping food too fast

If you free feed in a bowl and your dog gulps it down too fast. Try using this sturdy plastic bowl with rubber edge/feet. Product name: Slow Down! Dog Dish, by Top Paw. Distributed by Pacific Coast Distribution, PO Box 84613, Phoenix AZ, 85071.

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Start hand feeding some of their food. Use a portion of their kibble as training rewards. During training sessions. Going in and out of house well mannered, RECALL training (every day). Etc

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One gal suggested adding a tennis ball to the bowl. However, most dogs will pick it up and drop out of bowl. Perhaps select a different object?