I'm glad to see that Chloe bounced right back after you had gotten home. I think I would have been a little angry with the instructor for using her as an example for a dog that had shut down when the reason for the behavior was him.

I hadn't heard of a Volhard collar and had to look it up and it looks very familiar to the collar that Beni had on when I first picked him up 8 years ago. It isn't quite the same but very close.
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If there are no dogs in Heaven, then when I die I want to go where they went.