Dogs with separation anxiety may whine when you leave them, as well as engage in other behaviors, such as pacing, drooling and destruction at exit points. As with any situation where your dog is exhibiting heightened anxiety, punishment is not a useful training tool. If you punish your dog for whining, the vocalization may cease, but his anxiety will not change.
If your dog is excited, downplaying the greeting and refocusing his attention can lessens the whining.

A dog that whines when he is excited or nervous can also be taught to relax with settling exercises, such as a down stay.
He whines less frequently now, because he has been trained not to, but when he does vocalize, whining is his go-to expression. A dog who is showing appeasement behavior may whine as part of his interaction with other dogs or people. In fact, it may very likely become worse, and your dog may respond in a more dangerous way, such as biting.

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