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Tail is curving downward
(Forest, Ontario, Canada)
Last night our 15 yr. old Blue Heeler went out for a pee and never came back. Today, our 12 yr. old Jack Russell is, naturally, out of sorts, but he has completely stopped wagging his tail. He will play with us and run around but has not wagged his tail once today. All it takes, usually, is looking at him and it's going 20 mph. Also, his tail is curving down, sort of "hooked' looking, if that makes any sense. His tail is stiff, not limp. Is this maybe a sign of depression, and temporary? He has never been separated from Maggie. I tried googling the issue and nothing came up. Has anyone ever seen this?