A small dog shock collar for barking dogs that have a strong impulse to bark is a perfect and necessary gadget. These collars have a built-in sensor that will automatically activate when the dog barks and will send a shock back to the handler to punish them for their unruly behavior.
If you want to know why do dogs wag their tails. You should know that when dogs wag their tails, they are showing happiness, contentment, and joy. Some people believe that this behavior is related to communication and social interaction. When dogs see something that makes them happy, their tails will wag more violently than when they don't see anything that makes them happy.
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