Help! I think my rats’ eyes and nose are bleeding!

Author: Lydia Bardon, Editor: Jasmin Gregory

Are you worried because it appears that your rats are bleeding from the eyes or nose?

Fortunately, it is much more likely to be porphyrin, rather than blood. Porphyrin is a red pigmented tear that rats shed from their harderian glands (which are located behind the eyes). Porphyrin production and secretion is normal in itself and is not something to worry about. However, if it is excessive, frequent, or your rat is neglecting to groom themselves and there is staining or build up, there may be an underlying problem.

Excessive prophory production is called chromodacryorrhea. It is commonly caused by an inflammation of the harderian gland, which can be a symptom of diseases and infections, pain, or chronic stress. The treatment of chromodacryorrhea will depend on its cause. If it is caused by disease or infection, treating that underlying illness should reduce or eliminate symptoms.

In rats, the most commonly seen illness causing excess porphyrin is respiratory infections caused by mycoplasma. Pain can be assessed in rats using the Rat Grimace Scale. If your rat is displaying signs of illness (respiratory or otherwise) or pain be sure to take them in to see a rat knowledgeable vet for treatment.

If excess porphyrin is linked to chronic stress, then you will need to do some investigation into what is causing your rat stress. For example, you could look into the diet of your rats and see if they are in need of supplements. Perhaps they are lacking enrichment, and could use some fun new toys in their cages. They could be experiencing social stress and could benefit from desexing (either themselves being de-sexed or a cagemate) or a new friend.  Maybe you need to check your husbandry and make sure you’re meeting all of their needs and hitting goals for the size of your mischief.

Finally, rats often produce more porphyrin as they age. If your rat has sufficient enrichment, nutrition and husbandry and is in good health, but is just old, then you may not need to worry. Just give your little buddy a little extra care and help with grooming.

References

Graham,J, Schoeb, T, 2011, ‘Mycoplasma pulmonis in Rats’, Journal of Exotic Pet Medicine Vol 20, No 4. https://doi.org/10.1053/j.jepm.2011.07.004

‘Rats’, 2013, Clinical Veterinary Advisor, 242–252. https://doi.org/10.1016/B978-1-4160-3969-3.00138-4

Sotocinal, SG et al, 2011, ‘The Rat Grimace Scale: a partially automated method for quantifying pain in the laboratory rat via facial expressions.’, Molecular Pain vol.7, no. 55. https://www.nc3rs.org.uk/3rs-resources/grimace-scales/grimace-scale-rat