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Left my new rescue dog home alone for 20 minutes.(r/AnimalsBeingJerks)
Looks like separation anxiety.
Here’s what you do:
->Start crate training.
Get a crate big enough for the the dog to turn around comfortably in. Put soft things in it, feed the dog treats and pay lots of good attention to him/her when (s)he’s in it.
->Establish the dog’s current limits.
Get a webcam. Put it in a room with the dog, so that you have a good view of the whole room (you don’t want to start with the crate, as this might cause your dog to negatively associate with it). Remove everything from the room that you’ll be devastated if the dog destroys. (Make sure the webcam/computer is out of reach). Play with him/her for a few minutes, so that (s)he knows this is not a punishment. Leave the room and close the door. Watch the webcam, and note the time. How long until (s)he starts whining/acting anxious? This is your baseline.
->Use positive reinforcement.
Go back in, play with the dog. Leave the room for slightly less than your baseline time. If the dog tolerated your absence well, give him/her a treat and a “good dog!”. Leave the room for slightly longer and repeat. If the dog shows signs of being anxious, go back in, play with it, go outside for slightly less time. The idea here is to make it a game that rewards quiet and calm behavior. Make sure to pay attention to the dog, and if (s)he seems to be getting frustrated, spend some time reinforcing commands (s)he already knows to give him/her a break.
->Add in the crate.
Now that you have the basic “game” down, put the dog in the crate occasionally while you walk around the house. The dog shouldn’t be able to see you every once and a while. Reward quiet and calm behavior, especially when you’ve been out of eyesight. Rinse and repeat, following the outline of the original “game”.
->Other, misc tips:
Make sure to give the dog plenty of exercise, as a tired dog is a happy/calm dog.
Toys that require prolonged concentration are a good distraction from anxiety. I’m a fan of the buster cube myself.
Give the dog something to chew on, as chewing a chew toy is often a good outlet for stress. Something edible and designed to clean your dog’s teeth is great for this, with the added bonus of heather mouth and fresher breath. Booda bones makes some good stuff.
Give the dog something with your scent on it- an old, unwashed t-shirt is good for this.
A lot of people have had good results with a thundershirt, if you want to give that a shot.
You can also try borrowing a friends dog to see if having a friend (another dog) around helps- (s)he might just be a two-dog dog.
IF ALL ELSE FAILS…
You can talk to your vet about getting sedatives. But I really don’t recommend this route unless you’ve tried everything above and nothing works. Sedatives should also not be a long term thing if you can help it, so keep working on the “game” to hopefully get to a place where they’re not needed anymore.