Every dog I've ever owned (of at least four different breeds) reacted to vaccum cleaners oddly. They bolt in terror at the first sight of it, and sometimes bark hysterically. Surely other people notice similar trends.
I have two dogs, one of them will hide in the other room when the vacume is on and the other will try to get a ride from it, barking the entire time of course.
Dogs are scared of vacuum cleaners because the vacuum cleaner is louder than the dog. I have a quiet vacuum and the dogs aren't scared of it. Dogs are programmed to respect and/or fear loudness. This is why they bark at dogs or people they feel threatened by. When two dogs meet on the street, if they don't like each other, usually the louder one wins and the other one goes away without a fight.
It's kind of big and makes a loud growling sound when you move it. A dog has no idea what a vacuum is, so they end up barking, attacking it in fear.
A Dogs life sucks so bad that they are afraid of TURNING INTO a vacuum cleaner.
as you now a dog has a sensitive nose and a vaccum cleaner picks up and throughs cents around and dust you cant see ,the dog thinks that between the niose and the dust this vaccum guys got to go ,,,,,,,,,,,,,,totally disturbing his territory.
