Kennel Cough is airborne and has about a 10 day incubation period(dog has been exposed but shows no symptoms) So if your other dog had it in the last 2 weeks or so, that's likely where she got it from. My dogs got it two years ago from another dog team over a mile away. His dogs were all sick, we hadn't been there, but it blew down the road. It eventually worked it's way through every dog team in the Yukon practically! It took three weeks to go through all my dogs. The ones that showed signs first were perfectly healthy again by the time the last dogs got it. The only two who never coughed at all both came from big racing kennels and had some form of it previously.
Generally it's not serious. It's like a cold in humans and will run it's course regardless of what you do. My vet doesn't give anti-biotics or anything for it unless it's a young puppy who develops a fever. Kennel cough can turn into pnuemonia in some dogs. I did give a few of my dogs some plain cough syrup at night so they could rest(and so I could too!) Don't let her exercise while she has it. Exercise will only make her cough more. Don't let her near any other dogs. It's highly contagious. She may not feel like eating. That was my first clue that Raven was sick--she refused dinner. The next morning she was hacking! Make sure she keeps drinking. Add chicken broth or something tasty to her water if she doesn't drink much. It's important to keep her hydrated. In 10 days or so, she should be fine.
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