Q. One of my rabbit's temperature, within a day, drops and rises. My other rabbit has been starting to get red lining around her eyes
DR. MASSIMO ORIOLES, DVM, MRCVS
A. Upper respiratory tract infections are quite common in rabbits and can be quite dangerous (especially if a bacteria called Pasteurella is involved).
A part from respiratory tract, they can affect conjunctiva/eyes.
I would recommend to take them to your veterinarian as they may need some antibiotics and treatment in case of an infection.
DAVID ELBEZE, DVM, MRCVS
A. Depending on where you live, red lining around the eyes could be the start of Myxomatosis which is a fatal disease n rabbits. other signs would be swelling of the genitalia and ears as well as lethargy.
Other possible causes are mite infestation and ringworm, which are a more likely scenario if your rabbit is vaccinated.
If you are taking your rabbit temperature rectally i'm not surprised the temperature changes, it's often difficult to take their temperature and insert the thermometer properly so usually that's would be the reason why the temperature "changes".
I would advice taking her to the vet to get her diagnosed and treated as mite and ringworm cold potentially be caught by humans as well.