I agree with Jersey, once started, a course of antibiotics should always be followed through unless there are adverse reactions. If you start on abs then stop, you may have killed off the bacteria that are very sensitive to the abs, but a few tougher ones may remain. They can then multiply and keep evolving without having to compete with the very ab-sensitive bacteria, and next time you try the same abs, it may not work. That’s how bacterial-strains resistant to abs develop. (You may of course be aware of this, but many people may be reading this thread since we have many members, so I explain anyway).
The immune-defense of a young bunny isn’t fully developed, so they’re more prone to certain infectious diseases than adult bunnies. Give her lots of good quality hay, it helps her tummy to develop the good bacterial flora that is essential for bunny health (not just tummy-health).
That said, it’s not quite known why some rabbits are sensitive to pasteurella while so many other rabbits can carry pasteurella in their nasal cavities all their lives without ever getting the snuffles. There are many different strains of p. and some are more virulent (able to cause disease) than others. There may be hereditary components that make some rabbits genetically more sensitive than others, there may also be environmental factors like food and living arrangements and changes in diet and/or living arrangements, loneliness, boredom or stress from too much noise or other pets etc. I’d say it’s all important for the immune-defense. It’s probably not a myth that people who get their nutritional needs met and who have meaningful things to do and good friends to hang out with are healthier. Of course for a rabbit a meaningful thing to do can be very different from what a human considers meaningful. Stuff like destroying a cardboard house or chewing the bark off an apple-twig may be very rewarding for a bunny. As well as just lounging in the same room as her human, doing absolutely nothing.
.
