I'm actually working on a paper on pastuerellosis in rabbits for my immunology class. Most rabbits (and many other mammals and birds) carry latent, commensal pastuerella but it doesn't develop into clinical disease until the animal is stressed in some way(moving, pregnancy, illness, etc.). Baytril is not a bad place to start as it doesn't come with too many side effects, but many organisms have developed a resistance to it so there is a chance you may need to try one or more other antibiotics for treatment. Your vet should be able to culture her bacteria and test for resistance which may help you choose another antibiotic if Baytril doesn't do the job.