In his friendly greetings of other dogs on walks, my grey wags his tail, sniffs appropriately, and happily goes on his way. But I noticed recently that his hackles are always raised during these greetings, whether he's saying hi to a dachshund, a Great Dane, or even his greyhound bffs. Anyone else notice this with their hounds? I'd always heard that his is a sign of aggression, but he shows zero other signs of annoyance or fear. He loves other dogs of all shapes and sizes, so maybe it's more a display of excitement? Anyway, just curious to hear from others.