If a bunny falls to the side when it tries to hop, what comes to mind is e cuniculi or an ear infection. E cuniculi is a microorganism that can cause problems resembling a stroke in a human. An ear-infection can affect balance since the balance organs are located in the inner ear.
Laying flat makes me think of gas, but buns that have gas normally will refuse food. And gas wouldn’t cause a bunny to fall to the side.
Both e cuniculi and ear infections are serious conditions, so it’s best you take the bun to a vet and try to go as soon as you can.
Treatment for e cuniculi consists of Panacur (Fenbendazole, a dewormer) for 28 days, often plus Baytril (enrofloxacine, an antibiotic). There are additional meds that can be given to help with dizziness and nausea and inflammation. Treatment for an ear infection is antibiotics, commonly Baytril, and an antiinflammatory against pain and swelling (Metacam, meloxicam).
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